Nails vs. Screws – Test Videos and Pics
OK, Here are three tests comparing Nails and Screws. Sorry the pics and video are grainy – limitations of having no hosting myself.
Comparison of two 16d nail and two 3.5″ #9 Deck Mate screws, Toenailed into an HUS26 Hanger
Screws_vs_Nails_-_Toenail_Test_-_downloadable.wmv
Attached at the bottom is the Face attachment test, two 8d 1.5″ galvanized common to two 1.5″ #10 Round Washer head from McFeely’s.
Here is a new test – Shearwall!
Distance from pivot point was 15″, so the applied force this time was about 1000lbs.
I used 15/32 OSB (some scrap Radent barrier I had) and a total of 4 of each fastener: 2.5″ 8d Bright Common vs. Senco 2″ #8 Duraspin coated screws.
(You can see their code status at http://www.icc-es.org/reports/pdf_files/ICBO-ES/6068.pdf)
Here is how the nails faired:
The nail that looks like it’s coming from the bottom of the beam is actually still attached to the OSB. The tip of the nail pulled out then went under the edge of the beam
The screws did not fail… I won’t post a boring picture of screws staying in place and the OSB not giving way either, but here is what all 8 of the fasteners look like, side by side:
You can see a little bend in a couple of the screws. All the nails were obviously deformed by the force.
Any thoughts? Did these tests seem unfair to the nails?
Rebuilding my home in Cypress, CA
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Replies
xxPaulCPxx,
Did you see the article I used to compare the strength of screws to nails?
Actually to the strength of nails in simpson connnectors compared to the strength of just screws themselves?
A properly nailed roof rafter takes just 208 pounds to pry lose while a 3/8ths inch lag screw takes 2783 pounds (the wood fails while the screw remains in place..
Test done by Professor Henry Liu a civil engineer at the University of Mo. (the show me state) tests done for The Forest Products Journal july /august 1991 and reported and photographed for Tauton press's book on roofing!
Had the screw been properly installed I suspect that the numbers would have been much higher..
How thick were your rafters, and did you drive them perpendicular to the rafter or perpendicular to the top plate / ridge?Rebuilding my home in Cypress, CA
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xxPaulCPxx,
The top plate on the inside is a 12 x6 white oak timber, most are about 20 feet long so they land on top of a vertical where they are half lapped over the other.. and the rafters are 6x9 white oak timbers forming a scissor truss and the buttress beace goes from the scissor truss down to the vertical post.. . The buttress braces are curved on one side they start out as 6x9's and curve into 4 1/2 inches and then back out to 6x9's Everything is morticed and tenioned or birds mouthed except for horizontal joints which are simple half lapped..(although the tenion from the vertical joins both together)..
All of the lag screws were counterbored, drilled to the 1/2 inch shank diameter and then drill with a 3/8ths pilot hole (I cheated and had one(well actually several) drill bits made up to that size and almost all of the holes are from the outside in so you don't see any fasteners. There are two horizontal and three vertically on each joint (except the buttress braces)
The outer black walnut timbers are usually just morticed and tenioned and they are joined to the inner white oak timbers with 3/8th's inch lag bolts thru the SIP's. In order to prevent the inevitable dry rot that happens to timbers that go thru a heated space to an unheated outside space None of the inner timbers go outside and visa versa.. Where the roof uses 6x9 timbers as rafters, I lag bolted them to the verticals/horizontals.. With the roof overhangs at the 27/12 pitch and the 1/7 12 pitch there was plenty of "meat" to make sure the lag connection was solid..
I've never put sheathing up with anything other than ring shank nails. Including floor underlayment.
(Unless I intended to take it apart again later.)
Please do your test again, using ring shank nails. I'm betting they will be much closer to the screws.
I think the heads will pull through the wood before the nails will pull out. I wouldn't expect them to shear any sooner than the screws either.
Maybe try the test with something more solid than OSB. (Even though, yes, OSB is the most common sheathing used.)
Are we there yet ?
Yup, make them hot dipped galvy RS and watch the consternation of of a nebie w/o nippers.
Always a good time, unless yer PAYIN the one. LOL Spheramid Enterprises Architectural Woodworks
" out of kindness, i suppose"
Towns, the original.
Just got a few different boxes of ringshank to try them out - haven't seen galvanized ringshank yet though. Of course everyone around here seems to carry Grip Rite exclusivly - any better brands to look for, and anyone carry a ring shank Joist hanger nail -1.5"?
BTW, if you look at that picture again, you'll see that while the OSB let go of the top nail, it kept the bottom and pulled it out of the beam. The OSB was stronger than the nails fastening power - I didn't believe it was possible either until I tested and it happened!
Out of curiosity, do you think those face nails would have faired better if I would have used two and two, instead of one and one? (tested against two and two screws, of course).
Funny, there are those here who seem to want to stick their fingers in their eyes and go "LALALALALA I can't read you" rather than come to the defence of their beloved nailed shear wall. Doing a simple break test, it looks to me like screws are a MUCH better solution for a shear wall than nails are.
Is there a way to do this that will prove otherwise?Rebuilding my home in Cypress, CA
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This whole conversation baffles me.
My bona fides: I'm a nuclear engineer with a pretty strong grounding in statics and materials.
In shear, a nail and a screw will perform substantially the same if material (steel) quality, composition, and cross section are the same.
In tension, a screw will beat a nail by miles if material, quality and cross section are similar. This should be obvious.
Now if you want to know which will provide the strongest joint in just about ANY Simpson metal joiner gizmo, the answer is NAILS. Why? All Simpson hangers, or whatever, put the fastener in shear. The nails Simpson recommends JUST fit in the holes of the gizmo in question. Any screw that fit in their hanger or other gizmo would necessarily have a smaller diameter than the biggest nail that could fit.
It takes a ton of quality material to trump an ounce of cross section, in most decent grades of steel when in shear.
Chris
>>In shear, a nail and a screw will perform substantially the same if material (steel) quality, composition, and cross section are the same.Exactly the point I have tried to make. If the screw is not a frikken brittle drywall screw, but is made of the same steel as nails, and is of the same dimensions, there shouldn't be any difference in the shear. The pullout resistance is the big difference there.But....You make this point, and then you go on to make a statement that completely disregards the first point... You say that nails are always better than screws in hangers. Because when they are in a hanger, they are in shear.Again... If the screw and nail are of the same composition, and dimension... It doesn't matter if you have them in hangers, in sheathing, or in your ears... the shear is the same.And no, the hole does not have to be bigger for a screw.That is from no small amount of direct experience, not statistics...Besides, a screw could be made that would not have to be driven through the hole on a hanger, it could slip right through. But the last half inch of the shank could be a very snug fit in the hole.
Are we there yet ?
ChrisB-
We agree that modern wood screws are usually made with shanks that have a smaller OD than the OD of the threads (unlike old-fashioned wood screws). To me this is a good thing in normal wood-to-wood connections when screws are driven without driving pilot holes. Though you CAN drive a screw with a shank of the same OD as the hole in a hanger or fastener plate by forcing the screw to deform the fastener, most people wouldn't normally do so. It's therefore most likely that people will undersize the screw they use to substitute for hanger nails.
I think there's also some confusion between the mechanics of partial failure and total failure in a wood-wood joint reinforced with a hanger or other fastener plate. If we're concerned about the total disconnection of the two wood members, then the withdrawl resistance of screws may actually be more beneficial than mere shear strength of the fasteners themselves. But the deflections necessary to make this happen will cause severe damage to other components of the house, so it's a bit of a misleading test. If we're only concerned about unacceptable deflection of the joint when loaded purely in the design direction (i.e. putting the fasteners in pure shear), your argument about cross section seems to me to be valid.
McFeelys #10 1.5” Round Washer Head with No-Cor-Rode coating, .138” shank diameter (in place of 1.5” 8d Common nails or 2.5” 8d Common nails, with at best .131 shank)
McFeelys #10 3” Round Washer Head with No-Cor-Rode coating, .142” shank diameter (in place of 2.5” 8d Common nailswith at best .131 shank )
Phillips Deck Mate #9 3.5” Coated Screws, .148 shank diameter (in place of 8d 2.5” Common nails and 3.5”16d Common nails .162 shank)
So the #10 screws had a measured shank thickness larger than the supposed value of the 8d, though my actual measurements showed the nailes were thinner. I don't have the actual measured thickness of the 16d nails I used, but I was surprised when I actually sheared one off and another I tore the head. The #9 screws stayed in the wood and actually tore the 18ga. and 16ga. strap! No shearing. All fasteners fit easily into the holes provided on the plates and strap. Unfortunatly I didn't have tape of that test series - I do have the torn strap if you want to see it though.
I do appreciate you approching this with an enginnering background! I'm still trying to understand all the ramifications of these experiments.Rebuilding my home in Cypress, CA
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ChrisB
As far as you went you are correct.. however Tauton press published a test where the best Simson connector was compared to a simple 3/8ths in. lag bolt and the lag bolt was right there.. That's without properly installing the lag bolt, another words they just drove it in and when the connection failed it was the wood and not the lagscrew.. If they had properly predrilled the pilot hole the wood would most likely not have failed.
I don't know the brand name, but I have about 40# of ringer SS nails
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I'm not that familiar with the properties of SS nails. How to they hold up compared to their steel counterparts - are they softer or harder? Are they differnent to nail at all? Any galvanic reaction with the StrongTie plates?Rebuilding my home in Cypress, CA
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I don't know about screws and nails, but in my experience, SS bolts are extremely easy to twist off, compared to even the cheapest standard bolts I have ever used.Twist off meaning tighten the nut too much, and the end or the head of the bolt just twists right off.
Are we there yet ?
That's my experience too
Tried the ring shank just now, I'll post pictures later...
They failed too. 8d and 16d. They pulled out slightly less fast than the brights though.
Right now I've got 2 8d ring shanks with expanding polyurathane glue on it. Hopefully this might give them the edge they need to perform as well as the screws do - I'll find out in 22 hours when they dry completely.
It's not breaking my heart to have to put in nails - my new palm nailer makes that a breeze. It breaks my heart that I may have to put in fasteners that break or pull out with less load than what was there before.
"Take off that duck tape - only paper tape is approved around here" :)Rebuilding my home in Cypress, CA
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"They pulled out slightly less fast than the brights though."here is one of the problems with tests by novices. You should not be using brights for hanger nails to begin with
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How soon you forget. My original test was based on using Simpson joist hanger nails, which are galvanized but not ring shanked. I further expanded the testing to include other code approved nails, which are the 8d and 16d mentioned.
Here is a link to that original post Nails vs. Screws - Testing them out where we started this discussion.
As far as "You should not be using brights for hanger nails to begin with" HALLELUJA BROTHER! I'll sing that hymn with you loud and strong as we raise our voices together against what Code already accepts. Of course the next verse about my screws being better joist hanger fasteners will probably be a solo ;)Rebuilding my home in Cypress, CA
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as long as you can carry the tune...
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here is one of the problems with tests by novices. You should not be using brights for hanger nails to begin with
This novice was told by a guy at a lumber yard to use SS with joist hangers (I didn't).
People on this board have claimed that galvanization weakens nails, and that galvanized nails should only be used with PT lumber.... So I'm assuming those attitudes are reasonably widely held out there....
Taylor, you're my hero! :)Rebuilding my home in Cypress, CA
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I used 1-1/2" HDG JH nails for one end of joists holding up CI tub (only a rim joist there). Everything speced out, even with those nails and possibly only able to get in 6 of the 8 nails, each joist should be able to hold up the tub on its own.Then later I had to remove a joist hanger elsewhere with the 1-1/2" nails....holy mackerel.....If I could do it over, I'd probably pop a couple of 1-5/8" #8 round washer head screws in there for more holding power.... I might even try to bore some extra holes in the already installed hangers (with Simpson approval first of course....)My concern with screws is their brittleness and therefore long term performance....
Well, one thing I've learned with all the testing and trials and putting stuff in and taking back out of wood: Stay away from #8 screws (exception - I haven't tried the 18.6.1 class #8 wood screws yet).
I used #8 screws in a couple of places when i ran out of my #10's. There I found some had broken during installation, about 1 in 20. It was in an area where I was using them to help pull one piece of wood to another. I found the same with the longer 3" PrimeGuard woodscrews. Unfortunatly, #8 deck screws are the most common.
Use #10 McFeely's for shorter screws, use #9 3.5 Deck Mate Square Driv from Phillips for the longer replacements. None of these broke.Rebuilding my home in Cypress, CA
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how about this for a test ...
drive a screw in ... leave it about 1/4 or less proud.
Now ... sink a nail .. leave it out the same.
grab the head with the claw of your hammer ... and snap sideways.
I can snap the heads of deck screws all day long.
The most I'd do to a framing nail of any size is get my hammer stuck.
not sure if it actually proves anything ...
but nails win that one!
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
Am I the only one here willing to do an ACTUAL test to confirm or disprove a point? Not that this test actually mimics anything in the real life of a fastener unless it is a coat hanger, but what the heck - I'm game.
Just did your test on the Phillips Deck Mate Square Driv #8 3" (I had some laying around) and my #9 3.5". I now have two screws that each look like a sunflower. The head on the #8 is about 70 or 80 degrees, the head on the #9 is about 50 degrees.
OK everyone who is still skeptical over my findings, here is your homework assignment:
Next time you are at the Great Orange Menace (Home Depot - admit it, you go there sometimes too!), stop by the boxed nail and screw section and pick up some of the Phillips Deck Mate Square Drive #8 and #9 screws. Try them out, you will not be disappointed. These screws are not at all brittle. They even come in Pine Yellow and Redwood Red so you can keep them straight from the other crappy screws you are used to. Most people here do have an occasional job for a screw, these have tested out extraordinarily well.Rebuilding my home in Cypress, CA
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I just wish the HD sold the #9 deck mates in the 25 pound boxes like they do some of the smaller sizes.
"Am I the only one here willing to do an ACTUAL test to confirm or disprove a point?"
Uh ... no.
I wasn't making that up. I was stating proven fact ... for what ever it was worth.
Today wasn't my first day on a construction site. I have ... many ... many ... many ... times snapped the head of a deck screw with my claw hammer. Pretty easy to do if your side to side "flick" is quick and strong.
I've also demo'd more than one structure ... and know from previous experience ... than nails bend. And usually when U don't want them to.
It's a difference on how they're manufactured. I asked you before about this difference. That difference is why nails bend and screws snap.
I do like the idea of a threaded hanger fastener ... as long as the heads don't simple snap off.
I don't have to go build a set of horses out in the backyard ... neither does Mike ...
my feet hit the floor of the first jobsite when I was 8 years old ... I'm only 38 now ... but that still makes for 30 years of snapping off screw heads and bending nails.
can I request one more test from the lab?
How about getting a hanger ... and fill all the holes with appropriate hanger nails ...
then ... set a board across ... the other end trapped as in any regular framing situation ...
now ... jump up and down on it to your hearts content.
Let me know when it fails.
testing any product in it's applied situation is how real testing is done.
Saab doesn't fire missles at their cars then say they failed the safety checks.
I'd also suggest burying some coated sinkers into doubled 2x's ... and gun nailing some 16's into the same ... then spend a day with a cat's paw ... then come back and tell me just how easily nails slip back out.
If they came out so easily ... framing crews wouldn't go look for the sawzaw when a wall had to be moved.
Jeff
Buck Construction
Artistry In Carpentry
Pittsburgh Pa
Edited 6/22/2005 11:57 pm ET by JEFF J. BUCK
Oh, I do not doubt your experience. Like I said, there are ALOT of crummy screws out there - I've broken more than a few myself! However, try these screws and tell me if you think these are just like every other one you've snapped.
As for using the Sawzall - I thought they would do that because it makes good sense! BUzzzzzz right on through - no need to destroy wood or dig out a sunken nail head. Me, I'm stupid and pulled them them the long slow way. Believe me, I've pulled plenty of 16d nails, coated or not. Actually, I did pull 2 coated nails with my fingertips a couple days ago... see the post higher up with the picture.
You're not the first person on this thread who say they would LIKE to have an option of a treaded hanger fastener - presumably one that would fit in all those 8d/10d/16d holes. Let me ask you - and everyone else for that matter this:
What would make a code approved "Hanger Screw" work for you? What features would you find usefull, or manditory, for you to use it on select jobs?Rebuilding my home in Cypress, CA
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prime guard ... deck mate ... mcFeely's ... I've them all plus others.
they still simply deck screws ... their heads pop off like dandy lions.
and no way a coated sinker sunk into any framing ... unless it was balsa wood ...
is just "finger tip" tight!
what features on a code approved hanger screw?
uh ... pretty much code approved would do it for me.
what "features" does a screw have? It goes in ... stays there ... hold the intended load.
that's about it as far as features.
maybe a/c on a warm day?
btw ... I probaly should say this ... as yer way too into this as it is ... but since U are so into screwing ... get an impact driver. Your obsession will never be the same ...
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
I'm all over that impact driver - I added the Ryobi Impact to my fleet of 18v... yah, yah, everyone laughes at Ryobi... but I've dropped this gun on concrete numerous times and it still works great. I've even added the Ridgid 90 degree impact driver for those hard to reach areas.
Yep, I'm in it hook and line... wait wait, is that a sinker I see too? WOW - I can complete my collection <GULP>
As far as the "Hanger screw"...
Would you want it Phillips, Robertson, combo, torx? Hex head or no? Any finish you would find more usefull?Is a flatter or raised head better?Rebuilding my home in Cypress, CA
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How can you tell a crappy screw from a good one ?
Simpson used to sell hanger screws they probably still do.
Oh man this keeps coming up.... The Simpson #8x1.25 screws are not structural..... They have a piddling 50lbs of shear strength for crying out loud.... They aren't meant for much more than shelving.....
I used to use a couple of those screws to set and align the hangars then nail them.
I would not want to spend the time and expense of screwing all the hangers in.
Edited 6/23/2005 11:09 am ET by arrowpov
That's another meaningless test for Paul to cook the results on - 'cause he will not be able to muster the strength to snap the screw heads is he take twenty taps to drive a nail into a pre-drilled hole. It's hard to imagine him snapping anything stronger than a pretzle
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Hey now - I got thought the predrilled part in 2 whacks!
Gimme a break - I had to drive a nail through 2 whole inches of wood that wasn't drilled. My wrist still hurts, I had to have my 4 year old daughter kiss it to make it feel better.Rebuilding my home in Cypress, CA
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help me out here, Paul.When I do my needlework, should I pre-punch the holes? I so want the piece to look good when everybody sees it! I would just hate to screw it up!
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Well, if you were seaming the edge of thick leather, you might find it handy to pre punch those holes. Trying to force your way through it with a thick gauge needle could cause you to overload your stitch and rip it right through the edge.
But if you are talking about cloth, well that is basicly like sewing perforated hanger board. Cloth is made up of holes seperated by string.
Oh, and if you think I rigged my tests, please let me know how. Otherwise I might think you were calling me a liar! ;)
But what about you Piffin? If you could have a "Hanger Screw" made for you, what kind of features would you want?Rebuilding my home in Cypress, CA
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No lying - used rigged as a description of the skewed results. You are not likely skewing on purpose, but from lack of ability to normally install a nail in a piece of framing, you used abnormal methodology, resulting in skewed results for the testHere is where I consider this test and argument dangerous -
You try to make a case for using screws instead of nails, and look through the thread here at how many people did not at first notice that you performed the test with a very specificly designed screw. Those not payi9ng attention in class would go forth into the world of their work and just start using screws, instead of using "Special CRX Screws". They would over torque and under drive them, and use the wrong screws in a multitude of improper ways. The results would be hidden danger and a scarry situation.The rteason SR screws got pegged as "Piffin Screws" here is because I ride that hobby horse. Too many get used for things like hanging wall cabs and building staging! I sat in a safety course where the instructor showed a slide of a staging in collapse where three men had fallen a story and a half and one died. His comment still echoes in my ears - " Anybody wanna guess how these two bys were held together? Sheetrock screws!" What would I want to convert to your screwy cult?
The screw would need to be as strong as a nail, and install as quickly, and not require another tool. I can walk that beam and reach down to slam toenails into that LUS hanger with the hammer that is always there. to drive a scew, I would need a cordless driver up there too, to wear me out carrying it around, and slowing me down to get down on knees and fiddle the head into the bit, aim it and screw it.
So as long as I can drive the miracle screw with my hammer, and the code allows it, I would be fine with it
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
OK, If you say that driving a nail with more that three blows significantly weakens its holding power, please back up that claim. Surely there has to be a resource out there somewhere that you can point to to back up this contention. Perhaps a nail manufacturer FAQ or installation guide?
If you are saying that the extra vibrations from the extra hammer blows is CAUSING my nail failures, then what about other sources of vibration - especially stronger ones? What about the vibrating cause by putting another nail in next to the first one... or putting in 10 to 12 nails in wood in close proximity - as in say a Simpson connector? What about the vibrations from all the other framers working in your proximity? What about vibrations from transportation right of ways such as highways, railroads, and airports - wouldn't these also cause degradation of nail holding power?
If the nails are as susceptible to improper installation as you say - then there is no way they would be code approved for some of the same reasons you've mentioned screws aren't approved. There is no way for an Inspector to determine if the nails WERE installed properly - that they aren't "loose" in the holes due to too many taps to get them in. If they were that susceptible to improper installation, then everyone who you and others admonished to "stop hitting them with your purse" (great line BTW - LOL) should have been required to PULL EVERY NAIL THEY HAD TAPPED IN. Did you do that? Did everyone else?
Your supposition that "tapping" a nail in weakens its holding power is either Fact or Crap. I'd like to hear why it is the former, because it sure smells like the latter.
Now, as far as people who have responded to this and other screw related posts or threads: Look again at who wasn't reading what I was saying. Every response that mentioned "general screws" were by Nail Cultists (or Cuticles - those are right on the nail!) who were talking about how crappy their experience with screws have been. At every turn I explain that I am talking about specific screws, I list the brand name, the size and length, and the finish. I have links to the ECBO code page for one of the screws mentioned, and even describe where to buy them. The very first post in each of the threads is VERY specific about what screws I am talking about.
Now, If you are describing all the Pro's who have argued against using the screws as unable to read or comprehend my posts... well that's your fight. You've already pointed out the extra training and education you get to supplement your knowledge, I can't imagine the others doing anything less. If you are saying ANYONE reading my posts can go off and do something stupid, I won't argue with you there either. "People are too stupid to vote" is the only real argument against democracy, "People are too stupid to do work" is I suppose a valid offshoot of that.Rebuilding my home in Cypress, CA
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"OK, If you say that driving a nail with more that three blows significantly weakens its holding power, please back up that claim. Surely there has to be a resource out there somewhere that you can point to to back up this contention."The resource is the testimony of all the carpenters here on this forum who have stated from plain old experience. All of it adds up to hundreds of years worth. We know that the holding power of a nial is proprtional to the wood it displaces, as much a scientific fact as that the weight a ship can float is proportional to the water it displaces. Remove that wood by drilling and there is no displacement because it is not there in the first place. There is less friction on the shank of the nail. If you want to make the "test" somewhat more apples to apples predrill the scews fierst too. Admit it, you have a preidsposition to favor screws because you cannot drive a nail and are trying to justify yourself.We also know that when a nail is too tight to pull out and in danger of breaking off the hammer handle, the secret to getting it free moving is to drive it further in first, to loosen the wood fibres.We know all this from experience, seeing nails hold and screws break.If our testimony is not a resource worth hearing, what are you doing here?
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Just checking - do all the Pro's here believe that a nail driven in 3 blows (or less) has superior holding capability to one driven in 10 or more blows? Are there any specifics that you would like to add to this to clarify this?
As far as my predisposition, tell you what - try the test yourself.
All you need is a sawhorse, a 5' long 2x4 or 4x4, and some nails, and a Simpson connector.
This is a simple test that you can easily do yourself. If as you say the nails have different abilities when YOU drive them, then that board should have no problems holding you up. This test is so simple EVERYONE who has expressed an opinion here should try it. I'd like to hear you results.
If your nails don't pull out, i'd like to see a picture or video of it!Rebuilding my home in Cypress, CA
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Paul, could you post a picture of what it is you are saying? I'm having a bit of a problem understanding this test.
thanksRemodeling Contractor just outside the Glass City.
Quittin' Time
This is an illustration of what I was talking about. I realized that there needs to be an additional piece on the end to keep the board from rolling away when you stand on it. I think an A35 would work just fine for both the attachment hange and the hinge.
View Image
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Edited 6/27/2005 12:52 pm ET by xxPaulCPxx
That's what I thought you meant on the attachment of the board to a horse. You illustrate a correct splaying of the legs on the horse, omitting the top cut board which would project plumb up from the line of the legs. I know from experience you can take as much weight as the horses will handle and put it out there on the end of the cut board. However, If I attempt to stand out on the end of your test pc, the horse will take a nose dive long before I reach the end or the tie fails.
you trying to hurt somebody paul?
Remodeling Contractor just outside the Glass City.
Quittin' Time
There are laboratories that specialize in the testing of building materials and components. They have equipment that will apply pressure or tension, and keep a record over time of how much pressure or tension, and how far the item under test squashes or stretches. (They do a lot of this with samples of concrete to see how many pounds per square inch it takes to break it.)
To really see for sure if there's a difference, we should use the services of such a lab. We'd need to compare at least a hundred samples each of:
1. Nails driven in one rapid blow by a pneumatic gun
2. Nails driven in two or three whacks with a hammer
3. Nails driven in a few dozen light hammer taps
4. Nails driven in dozens to hundreds of taps from a palm nailer
5. Nails driven by slow continuous pressure, perhaps using an arbor press.
And all of those would need to be tested twice, once into solid lumber, and once into holes drilled to 75% of the nail diameter.
My guess is that the only big difference would be between solid and pre-drilled wood. Drilling reduces the distance the wood is displaced by the nail, and therefore the pressure it applies to the sides of the nail.
-- J.S.
paul.... nice presentation... but you're trying to fix something that ain't broke...
all of the codes were the result of catastrophic losses after Hurricane Andrew and the California freeway quakes.. the connectors and techniques are the result of those investigations
Simpson and others have responded by designing cost effective, repetitive connectors with specified nails that comply with those codes.
i can shoot the correct nail into every hole faster than you can drive two screws..
and Simpson has designed the connectors to perform under rated conditions..
since we work with code and code officials every day we will continue to build to code.. and please don't think you are exceeding code.. you're not.. you are ignoring code or trying to come up with code alternatives..
since we build in a high wind coastal zone... we have to comply with 120 or 110 mph design criteria.. we do.. there is no test you can devise that is going to exert the pressures our structures have to withstand
if you want to use screws.. go right ahead ..but you are being myopic in concentrating on a small portion of what builds a structure that can withstand some of the tests that mother nature has devisedMike Smith Rhode Island : Design / Build / Repair / Restore
Mike... didn't you just say this word for word earlier? Are you spamming or reiterating?Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Just checking - do all the Pro's here believe that a nail driven in 3 blows (or less) has superior holding capability to one driven in 10 or more blows?
I don't know. It's been quite a while since I drove one using substantially more than three hits, so I don't much care, either.
As far as my predisposition, tell you what - try the test yourself.
No, I won't be trying your test. Tell you what though, how about you try the one that all of us pro's live with evey day. Use your screws, your favorite ones, the best that you can find, and build something that requires a building permit, and an inspection.
Then tell us all about it when the inspector leaves.
This is a simple test that you can easily do yourself.
You are absolutely correct on that one point. This is a simple test. But it is also absolutely irrelevant. Unless you are properly trained and educated in the forces that affect fasteners in construction, then you have no business trying to convince us it isn't.
Or do you have access to that building full of engineers I mentioned last week?
Unless you're the lead dog, the view just never changes.
Is it absolutely irrelevent? The point of this whole thread was to examine some commonly held notions regarding screws compared with nails.
I looked at the following:
"You cannot use screws in Simpson connectors" - yes you can, check their FAQ. USG connectors also allows use of screws - specificly ones complying with section 18.6.1.
"Screws cannot hold Simpson connectors - they will shear off under load" - I tested this out and found the screws I was using do not. I did manage to shear cut a 16d nail though.
"Screws are brittle and will easily break" - I found through testing my screws to be quite malleble. They would quite easily match the bend that the nails had when the nails failed - but the screws would stay in.
"Screws are not code approved for shear wall construction" - I found the Senco Screws to be code approved replacements for 8d common nails, to be used exactly as the nails would be used in shear wall construction. Yes, you have undoubtedly "heard" about screws failing shear wall code - but were they properly installed Senco screws? Was the inspector shown the code form? My inspector wasn't familiar with the Senco screws either until I supplied the supporting documents.
"Screws will fail in a shear wall due to brittleness" - In testing I found this not to be the case. I found the Senco screws to be quite sturdy - stronger than the wood it was holding.
"Nails are better for shear wall construction" - Nails are better if your criteria is speed and using framing tools, no question they will go up much faster and more efficently this way. However, if strength is your top priority, my tests showed that the nails held the wood poorly, and even a 15/32 sheet of OSB was stonger than the nails bond with the underlying wood (i.e. the nail stayed in the OSB as it pulled out of the stud).
Now in rebuttal to what I've outlined above, some have dismissed my findings by saying that my nailing technique is what caused the poor performance on the nails in the tests. So now, in addition to the above claims, we have the following:
"Nails must be driven into wood with a minimum of blows to ensure the best hold from the wood" - The person who posed this went as far as to say that even palm nailers give nails a sub-optimum grip. This seems preposterous to me for a number of different reasons that I've outlined already. Since that poster made that statement, I've given instructions on how that claim can be easily tested. If my test method is suspect, then I put the tools in your hands so you can prove me wrong. If someone runs the test and can show me different results, I'll find someone to bang some nails in 3 whacks and run my series all over again. I'm looking for the truth, not to be right.
"The holding power of a nail is proportional to the wood it displaces, therefore predrilling a hole will reduce the hold from the wood" - Again, this doesn't make sense to me. For maximum hold, you need as much surface contact as possible to apply friction against. Since most nailing occures perpendicular to the grain, wood splitting is more a question of degree than if it happens or not. When the wood splits, even minutely, you loose the 360 degrees of face contact on the shaft of the nail. Going into a prebored hole of a lesser diameter than the nail shaft, the wood fibers are compressed the full 360 degrees around the nail shaft. With that extra contact, there is greater force required to overcome the friction that prevents the shaft from moving... at least that's how I envision it. But then again, Professor Bruce Hoadley is a better authority on the matter and he says predrilling produces a better hold too. Though we haven't discussed a test of this specific theory, I do have one buzzing around that might test this theory out too. But the prerequisit is that the nailing tecnique question be answered first.
So if you subscribe to any of the statements in bold above, and I can show that they are either wrong or have significant exceptions, then is it irrelevent to you? I'm not suggesting you change your constuction techniques, I just would like to know if the theories behind them are sound.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
I've enjoyed reading about your tests and all, but I don't think you're going to convince the pro's to change. Nails have performed well for eternity, and they are efficient.
I'm not a professional tradesman, but I pretty much use nails for most everything I build. I like to whop em in with a hammer. I do use screws where they are better. I find their cost to be pretty high relative to nails, and they seem to almost all be from third world countries, and have more dubious quality than in the past.
And whats up with the combo drive screws that dont fit square or phillips well, and the free bit that comes in the box of typical crappy quality you get with a "free" tool.
Hang in there.
Some times..simple old adages explain it quite simply.
When we are rockin along and all looks sweet the common command is " Nail it" or " Nail'er up, buddy"
When some thing is awry, or even FUBAR...what do ya hear?
"Ah, SCREW it"
Point made.? Spheramid Enterprises Architectural Woodworks
"Viva!!! Chileo" !!!! The man with a golden heart. And a Thumbs up attitude.
I'm not asking anyone to change, just be willing to examine what they believe to be true.
I find it funny that people interpret my questions or findings as an imperitive to change their way of life... really guys, I'm not the Emperor. It is possible to talk about something without you actually having to do it my way! Honest!Rebuilding my home in Cypress, CA
Also a CRX fanatic!
So if you subscribe to any of the statements in bold above, and I can show that they are either wrong or have significant exceptions, then is it irrelevent to you?
I've mentioned that roomfull of engineers a number of times now, in the hopes that you would explain your qualifications. You haven't, so I must believe that you are not qualified to be making statements about "wrong" things in the codes and in my construction techniques. And since you do not have those qualifications, it really is time for you to stop this nonsense.
I'm not suggesting you change your constuction techniques, I just would like to know if the theories behind them are sound.
First, I believe that you are suggesting that I change my techniques. If that weren't your premise, you wouldn't be doing this on a forum of builders -- you'd be on a forum of philosophers, or theoreticians, or engineers.
As to whether the theories behind my techniques are sound.....suggestion otherwise is absolutely ludicrous. The "theories behind" my techniques have been adopted into the International Building Code. They are supported by sound engineering, and years of rigorous testing.
So whether or not I "subscribe to any of the statements" you reference, I still believe that your tests are absolutely irrelevant.
Unless you're the lead dog, the view just never changes.
Just checking - do all the Pro's here believe that a nail driven in 3 blows (or less) has superior holding capability to one driven in 10 or more blows? Are there any specifics that you would like to add to this to clarify this?
You missed the point Paul.
The ten tap vs three slams is a facetious comment intended to draw attention to your framing inexperience. All of us that read it understood the comment perfectly. Now, you want us to comment on the validity of your technical argument regarding the scientific merits of the comment. This further proves that you lack techical experience in the trades and it serves as a warning to others to be wary of your "tests" which prove basically, well, nothing!
Go ahead, start making those titnium handcrafted screwshanked nails and please, include an expanding tip to further increase holding power. Once you've done that, I'll truly believe that you are interested in really building something that will stand the test of time. If you don't do that, your no better than me and many in here will tell you that I'm nothing more than a Boogerin' hack, and proud of it.
I've built things for 30 years and everythings still standing.
blue
blue
Well, if I really thought a Titanium nail would do the trick mabey. Did you follow that link, BTW? ;)
OK, so you're saying everyone was talking out their butts about that and I missed the joke - oops!
So then, you're saying the nails held exactly as they should have in my tests, where they all failed to hold compared to my screws. OK. Cool!Rebuilding my home in Cypress, CA
Also a CRX fanatic!
So then, you're saying the nails held exactly as they should have in my tests, where they all failed to hold compared to my screws. OK. Cool
Paul, around here, it's not polite to restate someone's words. Our words are already in print, so we don't need you using that kindygarten trick to try to make a point.
In my first response, I mentioned that your test is silly and that you would be much better off putting in all the nails, then testing to see if it meets the design loading criteria. Any test that shorts that process is simply irrelevent.
If you are trying to tell me that screws have more holding power, I'll quickly agree. That doesn't need any goofy test other than a good claw hammer.
If your trying to tell me that screws are superior to nails in hangers, then I'll keep responding that hand crafted, titanium screwshanked nails are superior to your screws. Whoopeddedoopdee. Both claims are equally useless.
If you really want a strong building, build a pyramid bigger than those that have already stood the test of time.
blue
I did your test (unintentionally) the other day and snapped the head off a 16d nail. I guess that nail is in there forever....Of course it was a POS GripRite....
Not sure what you are saying here.SS are not brights. Neither are galvies.bwecause of proximity to salt water, we use only hot dipped galvies or SS anils on all exterior work and structural work
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Only agreeing with you. Any galvanic reaction between bright nail and HDG hanger (I assume that's what you were warning against) would be only worse with SS nails.I was advised by a Simpson rep that I could use SS nails with zmax hangers if I used plastic washers. Interesting idea but I chickened out, there's still that contact point where the hanger rests on the nail shank. I was looking for an alternative to POS GripRite galvanized nails in 3" 10d. Ended up going with the Simpson JH nails, not my first choice.I was interested to read your earlier comments about SS bolts, which I'm planning to use for sistering joists. I saw corrosion on lags that I took out after only being in a few months. Would your problems go away if you lubricated before fastening the nut?
taylor.... we don't allow bright nails on our jobs.. they always get picked up and used in the wrong place by someone or other
all hand nails are either HDG or SS
a lot of our gun nails we special order to get HDG..
and as far as screws ... i've been driving screws since '54... when we started we used to use a brace and bit to speed it up ( slot head ) then phillips came along.. even faster.. then square drive & torx...
we've used every fastener named on this board..
but this conversation is a lot like putting high test in your engine if it's designed to run on 87 octane..
and i'll bet that my building techniques for longevity will stand up to anything you , or frenchy, or paul is describing..
in short.. we overbuild.. but our houses last.. and our exterior details last.. and it has nothing to do with using or not using screwsMike Smith Rhode Island : Design / Build / Repair / Restore
Just to clarify, I'm not advocating for screws, I have my doubts about them, just want to make sure the arguments are valid.... So the reasons I see for using nails are:- economy (as long as we recognize we are compromising by not preboring, but life is a compromise)
- flexibility (which could be either a good or bad thing, but they are not brittle, so failure mode is less instantaneous)The first is probably of less importance to a DIYer, at least the kind of manic control freak that probably inhabits this board (nervous cough).The second is one that would give me pause....
There are differences even betrween different SS nails.Generally, they are more brittle than regtular, but not as brittle as screws. Siding SS nails are fines so very easy to snap off. One must be skilled with a hammer for them. hanger nails are fairly heavy though. All are ring shanked so they hold extremely well against pulll out. SS is very inert and non-reactive which is why we are changing to them for use with newest PT lumber.
Screws or galvanized nails are coated and that coating can be stripped off as it enters the hole for hangers, leaving the bare metal in contact withgt the copper. SS is same throguht the section
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I know about crappy SS..it varies. AND the price is ? at best.
Scroll down a tad, about SS demand and why it is so volitol.
http://www.ironax.com/#ggviewer-offsite-nav-8991296
edit
ooops..lemme try that a step up a notch..
Nope, this ain't my computer and the controls for active x are DOA.
sorry
Spheramid Enterprises Architectural Woodworks
" out of kindness, i suppose"
Towns, the original.
Edited 6/19/2005 7:39 pm ET by SPHERE
Paul,What good is a test that uses two screws but only one nail ?Do the test with exactly the same number of fasteners. In exactly the same pattern. Get as close as possible in the makeup and dimension of the two fasteners as possible.Do that with ring shanks, and I am still willing to bet they are as good as or better than screws.Another thing to consider is whether a nail is hammered or shot in.I learned in the first year I worked as a carpenter that nails don't go in straight. They tend to go in at an angle, because of the way we hold them. And that turned out to be a good thing. Because once you realize it, and you have hammered a few hundred after that realization, it becomes second nature to put the correct angle on the nail, to work against pullout. Sometimes you drive nails in at angles toward each other for even more pullout resistance. All bets are off when it comes to nailguns.If there is a 1/2" gap between the sheathing, and the stud, when you shoot a nail in there, the gap is still there.Every time I have mentioned this about nailguns, guys always talk big talk about how they make sure that all gaps are taken up before they shoot. But I have never seen anyone actually do that. And I HAVE seen countless gaps in structures, between dimensional lumber, as well as between the dinmensional and sheathing... All caused by guys just shooting for speed.A hammered nail will always take up the gap.Nailguns are good for trim and cabinetry. But I think that until they can come up with a way to force everyone to take up the gaps, big nailguns should be outlawed.When the gap is there, the joint is already 99% of the way towards failure.People rail about how the modern homes don't stand up as well as the old ones. I marvel that some that I have seen don't simply fall down the first time someone farts nearby.
Are we there yet ?
Sorry, I may have typo somewhere. There was one fastener on each board, connected with the strap. Either one screw per side or one nail per side. I was wondering if using two of each per side might reveal a hidden streangth of nails.
You can see me place and pound the nails. They look to be at 90 degrees to the surface - you can be the judge though when you look at the video. All nails were hand hammered, BTW, and I ensureed that there was no gap between that materials being fastened.
I do intend on using the ring shanks, possibly today. I will give updates.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
If I am not misreading, there seems to be discussion around attaching Simpson hangers here...I think you used only 2 nails or screws, right? IMHO hangers should always be used with the nails designed for them - the short fat JH nails. Ads to how many - well, that's why ALL the holes are there. If you're forming a built-up beam then there are recommendations that some of the short nails be replaced with longer ones that'll transfer the load to the 2nd member in the b/up. As to whether it's nails or screws - I'll have to finish this thread first!cheers
***I'm a contractor - but I'm trying to go straight!***
Yes, that is what we are talking about, but check the link in my reply to Piffin for the full story on that test.
I was told that nails are supposed to be put into Simpson products, and that screws just wouldn't cut it. Being a skeptic with a long history of using screws, I decided to put this "common sense" contention to the test.
I wanted to test nail fastener performance against a specific screw fastener. I set up the test so the each fastener would have force applied to it by a Simpson product in the direction that it was supposed to be applied. The force direction is of course in shear, which should minimize the chance of fastener pullout and maximise the theoretical holding power of the fastener used.
Now, I purposly scaled the test down, as it required alot more force to test a fully filled out LTP4 and would also require recutting and rebuilding the test bench each time. Now the strap is the same thickness as the other Simpson products, and instead of testing 4 fasteners (two at the top and two at the bottom), I used two . I decided that the results would be theoreticly valid enough for a direct comparison. Now, if one nail gives way at under 890 lbs and the screw does not, my theory is that a liner progresion could be drawn from that starting point: 2 nails should give way at under 1780 lbs. and two screws should hold at over 1780 lbs.
Now, if you can describe to me a property unique to nails that would allow 8 or 12 of them to hold better than 8 or 12 screws when each individual screw has already been proven to hold better than each individual nail (phew, long sentance) then I would like to hear it - I actually was pondering this in my original post at the top of the thread.
I was using the short fat Joist Hanger nails, the 1.5" 8d Galvanized ones made by Simpson for this purpose!Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Thanks for the elucidation, and compliments on your tests....
I am reminded of the great discussions years ago as to whether a propeller-driven boat was more powerful than a paddle steamer - it took Brunel (I believe) to arrange for a test whereby the boats were chained stern to stern and asked to try and pull the other. The propeller boat won - screws again! - and that is how it's done. You, in your way, have tried to show this and whilst it isn't a controlled lab test it does show sceptics an answer.
The only time I had recourse to an engineer he specified nails at the point of contact. Not that screws wouldn't work. But they could not, for instance, be air nails. We don't have the same nomenclature in Canada - a 3" nail is a 3" nail - so when he asked for that size it was downright important that I used hand nails. (But then, engineers are overly-cautious). It may not have dawned on him that screws could do the job better
I recognise the fact that screws do do a better job, but until the Building Codes allow for that I presume that things will continue as they are.
All power to youcheers
***I'm a contractor - but I'm trying to go straight!***
Thank you for your generous words.
Piffin and a few others brought up some great points about the potential weaknesses of screws for this particular purpose. While I can say that these screws will do the job, I will only say that about THESE SCREWS ONLY if they are INSTALLED CORRECTLY. I do understand the the building codes are written for the safetey of all, and that safety isn't assured with the variaty and non-standardization of screw based fasteners.
I think there would be a market for a code approved screw based fasteners for metal to wood connectors. Even if it isn't for the production construction framers, I could see the DIY and even specialty installers jumping all over this.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
I think there would be a market for a code approved screw based fasteners for metal to wood connectors. Even if it isn't for the production construction framers, I could see the DIY and even specialty installers jumping all over this.
I agree that there would be a market (and I'm the guy whose first reply to your first post talked about the building full of engineers being more relevant thatn yuor tests). And not just for DIY. Remodel jobs, and some home repair jobs scream out for approved screws.
As an example, I am now finishing a repair job in a home with a crawlspace. I had to remove about 10 feet of a main beam, and the ends of 8 or 9 joists, all of which had rotted from a leaky shower.
After rebuilding and placing the beam, I needed an approved method of re-connecting the joists. Given the very tight quarters, I really wanted to use some square-drive screws. After all, a drill driver with a square drive screw can be used at full arm's extension -- not true with a hammer, or a palm nailer, and sometimes impossible with a positive placement nailgun.
Tell you what.......when you get the patent, and need some investors, send me a request.
Unless you're the lead dog, the view just never changes.
Here is the shear data for GRK structural screws (over 800 lbs per screw):http://www.grkfasteners.com/technical_data.htmThe shanks on these screws are too large (5/16") for most hangers and too long (2-1/2" min) for many applications. I have had custom metal plates cut and drilled for these screws to mend cracked beams, etc. The shear and tear out values for these screws was so high that I was able to use them in lieu of through bolting of mending plates. I staggered the holes and used 8 screws per plate for a shear value of 11,000 lbs per plate and tearout values of 35,000 lbs per plate. It would be nice to see a version for hangers and other structural metal ties.
Been 24 hours now, and the test results are in...
<HarryCareyVoice>NAILS PASS! NAILS PASS!</HarryCareyVoice>
I went and stood on the lever just now, and for the FIRST TIME in my dozens of tests, Nails hold just as well as screws. The 8d ringshank nails with a drop of expanding Urathane Glue (elmers, not gorrilla) were able to hold in the same weight range as screws. Not even a hint of bending and pulling out, as it did without the glue.
At last, I have a nailing technique that gives me as much confidence as the screws do. Now... I wonder what would happen if I glued the screws... :>
Hmmm. Now I just have to figure out how to pull those out so I can disassemble it again!Rebuilding my home in Cypress, CA
Also a CRX fanatic!
I'm surprised that in areas where they require all the extra straps, etc... they don't already require glue for all the sheathing.
Are we there yet ?
BTW, the glue went in the hole with the nail! The glue was the only thing that would keep the nails in the wood under load!Rebuilding my home in Cypress, CA
Also a CRX fanatic!
> BTW, the glue went in the hole with the nail! The glue was the only thing that would keep the nails in the wood under load!
How did you make that happen? Did you put the nail into a pre-drilled hole with glue in it? If so, that's nothing like what happens when nails are driven into solid wood. If you drove the nail into solid wood thru a dab of glue, the wood would wipe the glue off the nail, not carry it into the hole. The glue would remain on the surface, and get squished out between the sheathing and framing, forming a glue joint there.
If you want the strongest possible connection, glue is the way to go. Its shear strength in pounds per square inch may be lower than steel, but if you do it right, you have overwhelmingly more square inches, and a much stronger joint. The downside is that though it breaks at a much higher load, when it breaks, it fails instantly with no warning. A nailed structure creaks and groans and shifts a little as it starts to fail.
-- J.S.
The screws did not fail... .. YOU BET!... But you did not have the cheepo ones from China.. Heads pop off!
EDIT: ring shank nails.. Almost as good.. Or maybe better... Especially if coated nails!
Edited 6/19/2005 2:25 pm ET by Will George
Actually, the McFeely's are made in China - though they certainly aren't cheap! But I tested the Grip Rite screws as well, and those were little metal P.O.S. I agree with everyone who says there are substandard screws out there. The screws I tested appear to be better than the standard (which would be nails).
As for ring shank - they only proved to be better when I put a dab of polyurathane expanding glue on them. I expected different, but was proven wrong in testing.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
paul.... i watched your video...interesting..
you nail like a girl..your test would be uch more palatible if you drove the nails with 3 whacks instead of twenty taps
the problem with your test is that it's being conducted by someone with no background in construction...
personally... i find the use of screws to be vastly overdone... and mostly by people who don't know how to select or drive the appropriate nail
but, hey, whadda i no ?
gawd, that much extrra vibration and distorttion of the wood from all that tapping away would ruin any connection friction, even with ring shanks! to make a valid comparison, he'd have to run the screw in and out twenty times in the same hole to know anything.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
yup.... nails were gud enuf fer my pappy & they're gud enuf fer me.....Mike Smith Rhode Island : Design / Build / Repair / Restore
OK, So I nail "incorrectly", and so my wussy taps alter the atomic spin of the carbon and the steel is put into flux, and flux is slippery so the nails just fell out - is that what you are getting at?
If that is the case, is my palm nailer also just as suspect? The one I used on the ring shanks, BTW, that still popped right out.
OK, is this a challenge then? Are you saying that if I drive a nail with only 3 whacks (or less) it will suddenly have MORE holding capability than the screws?
Oh, and I may get booted out of the Chorus if I have to audition. The best place to hear me sing is in a building where you can't hear me!
Edited 6/21/2005 11:34 am ET by xxPaulCPxx
> If that is the case, is my palm nailer also just as suspect?
Yes. One downside to a palm nailer is that it won't suck up the gaps the way hammering does.
-- J.S.
Well, I am looking at the metal, the wood, and the nail. No gaps anywhere, and I'm pretty intolerent of gaps anyway since I like to use screws.
But gaps weren't what they were saying was the cause of the nail failure. They were saying that "vibrations" prevented the nails from "Getting a good grip".
If that's the case, wouldn't houses next to highways or railroad tracks be subject to extreme nail failure, as they have vibrations transmitted through them day in and day out for decades?
Are there any sources I could look at to back up this contention?Rebuilding my home in Cypress, CA
Also a CRX fanatic!
at least ya made me curious enough to watch the first minute or two!
tap tap tap ...
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
almost as girly as dem pirates bats on sundayMike Smith Rhode Island : Design / Build / Repair / Restore
yes .. but more important questions still exist ...
did Amber wear her Pirates hat ...
or did Rob make her go "Boston" ...
these are the questions we need answered.
also as about as relevant as tapping in two nails in a joist hanger then standing on the board sideways ...
and people wonder why we don't type paragraphs on certain subjects.
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
Paul, I'm in agreement with Mike on this issue.
Your test is faulty and it's also irrelevant for most hanger connections.
If your trying to find the strongest possible joint, why not hand craft some titantium screwshanked nails? Make them the largest possible diameter to fit the holes in the hanger and make them long enough to penetrate the entire depth of the wood. Dont predrill. Nail them in and then test them against your screws. You'll find that the handcrafted titanium nails are far stronger.
After that, try to hire yourself out as a joist hanger specialist.
Apply for welfare. You'll need it to eat.
My point it that you are trying to prove that screws are stronger, but the need for stronger fasteners isn't needed. If the connection requires more strength, the manufacturer simply puts another hole. If ten holes aren't enough, then they put 12 or 15. Fill all the holes and the joint is good enough.
Your test is faulty because you predrilled the nail holes. You screwheads are so fixated on screwing things up (double entendre intended), than you fail to realize that the nails rely on the crushing grip of the wood that holds the nail tite. When you predrilled the nail holes, you botched the test.
Please, get a man's hammer to drive some manly spikes in there.
blue
blue... how goes the battle ?
hope you're laying tracks for calvin's do...
Helen and I are probably going to make a side trip after to Pontiac & RochesterMike Smith Rhode Island : Design / Build / Repair / Restore
Mike, the battle rages on. Michigan's economy sucks and I'm sick of it! We have the highest unemployment in the US and everyone is talking about how slow it is compared to most summers. The commercial guys are dead and low balling everything.
I was thinking I might be out of here by August, but it looks like I'll be here a little longer. If I'm here, I'll be in Toledo.
blue
Actually, only the "joist" was predrilled. The bit wasn't long enough to reach more than 1/4 inch tops into the beam itself.
So, are you saying that if I don't predrill that hole, the nails will suddenly perform better than the screws?
And the point is not to be just good enough.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
paul.... nice presentation... but you're trying to fix something that ain't broke...
all of the codes were the result of catastrophic losses after Hurricane Andrew and the California freeway quakes.. the connectors and techniques are the result of those investigations
Simpson and others have responded by designing cost effective, repetitive connectors with specified nails that comply with those codes.
i can shoot the correct nail into every hole faster than you can drive two screws..
and Simpson has designed the connectors to perform under rated conditions..
since we work with code and code officials every day we will continue to build to code.. and please don't think you are exceeding code.. you're not.. you are ignoring code or trying to come up with code alternatives..
since we build in a high wind coastal zone... we have to comply with 120 or 110 mph design criteria.. we do.. there is no test you can devise that is going to exert the pressures our structures have to withstand
if you want to use screws.. go right ahead ..but you are being myopic in concentrating on a small portion of what builds a structure that can withstand some of the tests that mother nature has devised
here's a hint.... don't choke up on your bat ( hammer )Mike Smith Rhode Island : Design / Build / Repair / Restore
Mike
In short you are wrong and xxPaulCPxx is right!
At least Tauton press has proved it.. Read the test they did comparing Simpson connectors to a 3/8ths inch lag screw.. Page 126 to 129. The lag screw held longer than the wood did while almost every other connector Simpson had failed by tearing..
Had they properly predrilled for the lag screw I suspect that the lag screw would have held much longer.
Do this test to satisfy yourself, Hammer a nail almost all the way in (leave enough to get a hammer under it to pull it out) now measure the force it takes to remiove that nail, then run the same size screw into the same piece of wood leave it just as high and using your hammer try to remove that same screw..
Speaking of girly taps, I am getting old and it probably takes me 4 whacks to seat a nail that size compared to your 3 whacks. I guess that makes me a girly man but the facts remain the same, screws are superior at holding than nails are.
frenchy... what am i wrong about ? that paul doesn't work in the trades ?
that what he is proposing doesn't meet code?
that the connectors are designed to meet the requirements with teco nails ?
what?
just another homeowner trying to reinvent the wheel...Mike Smith Rhode Island : Design / Build / Repair / Restore
frenchy....
<<< Do this test to satisfy yourself, Hammer a nail almost all the way in (leave enough to get a hammer under it to pull it out) now measure the force it takes to remiove that nail, then run the same size screw into the same piece of wood leave it just as high and using your hammer try to remove that same screw.. >>>
do this test to satisfy yourself..
take a 22 cal.... put it up next to a squirrel...
pull the trigger..
now take a 45 cal.. put it up next to asquirrel..
pull the trigger..
same result , right... but one is overkill, and one is notMike Smith Rhode Island : Design / Build / Repair / Restore
Are screws overkill here? Yes they are. But I look at it this way: If the wood my ties are attached to degrades due to water damage, fungus rot, termites, cracking, or any number of other ills, I know that I can have 8 of the 10 fasteners removed from the equasion AND STILL exceed the load capacity on the tie.
Example, the 18ga strap is rated to hold 1370lbs using 20 10d nails (10 on each side of the Clear Span). I've found that one of my screws holds about 900 lbs. So if I have a hidden leak or bug infestation in a piece of lumber that I use that strap on, I know that there only has to be good wood holding in just 2 screws to still meet the allowable load the strap is rated for.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Paul, I'm saying: "Don't pre-drill nail holes." It reduces the holding power.
And I'm also saying, that I don't think you're as quality conscious as you are trying to make yourself out to be. I know this, because you didn't show any tests with the handcrafted titanium screwshanked nails.
Hand crafted titanium screwshanked nails are superior to your screws. IF you don't make em and use em, then you're nothing more than a boogerin' fly-by-night!
Now, run the test with the full compliment of nails. Use 16d cement coated sinkers or shoot them with a nailgun. Apply the load that the hanger is designed to carry. If it fails, then I'll agree that your efforts are worthwhile. If it carries, then I'll never agree that there is any reason to use anything stronger.
If you truly want the strongest house possible, just carve your house out of a solid titanium block.
blue
> I'm saying: "Don't pre-drill nail holes." It reduces the holding power.
Pre-drilling is only allowed for the piece that gets the nail head against it. The maximum hole diameter allowed is 75% of the nail diameter -- like 1/8" for a 16d.
The only reason to pre-drill is if the wood would split without it. A pre-drilled piece is stronger than a split one, but not as good as one that doesn't split without drilling.
-- J.S.
That is what I drilled, thoungh the bit might have been one size smaller, like 7/64. Since in this case I am toenailing through the end of the board, it needs to be predrilled to avoid splitting... unless Blue Eyes can come up with a reason that split wood holds nails better ;)
And if you watch closely at the end of the video, you will see the the nails were bent out the end of the wood grain. The nails that were in the predrilled wood stayed straight and didn't destroy the wood. Where the nails went though undrilled wood they pulled out - even though the force directing was in shear. They bent in half as they slipped out of the wood.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
> I'm saying: "Don't pre-drill nail holes." It reduces the holding power.
The only reason to pre-drill is if the wood would split without it. A pre-drilled piece is stronger than a split one, but not as good as one that doesn't split without drilling.
From "Understanding Wood" by Bruce Hoadley, p 189:
"The fact that nails can be driven without preboring pilot holes has apparently led to the assumption that they should be driven without preboring. An unfortunate corollary seems to be that nails are therefore limited to use where they can be driven without splitting the wood or bending over. In reality, the best holding power results when nail holes are prebored [Emphasis added]. While most woodworkers accept the idea of installing woodscrews in prebored holes to prevent splitting and to maximize holding power, they seldom consider preboring nail holes."
Take a look at this comparison of decking nails, including various screwshanked nails:http://www.timber.org.au/resources/Residential%20Timber%20Decking%20Nail%20Trial1.pdf
The best of them could withstand 4kg of withdrawal force on its BEST pass. The #8 50mm SS screw, in contrast held 8kg of withdrawal force on its WORST pass.
In my tests, all of the nails bent and slid out of the wood in pure shear loads. If the titanium was to somehow not bend, then it's possible that it could stay in place. The nails failed because when they bent, they turned the shear force into a pullout force. I don't have a piece of 1/8" titanium dowel so I can't tell you. But from the results of my testing, it isn't likely in my opinion.
As for my method of gluing a nail:
- Fasten 1.5" #10 screw to wood then remove it. - If wood is dry, use syringe to squirt in a drop of water into the hole. - Place a drop or two of expanding polyurethane glue (Gorilla Glue or similar) to an 8d Ringshank common nail, or squirt them into the hole. - Pound in nail. - Wait 24 hours before load testing.
When I did remove them today, I found the glue did ride the rings in the shank into undrilled new wood and there was where it held. Since it had 0 pullout, the head bent under load but pivoted and pulled the force into the wood instead of out of it.
By the way, I came up with that method to address a specific need. If I did have to pull some of the #10 screws I've already placed, I'd have to have a way of secureing the nails within the existing holes.
By the way, about those 16d cement coated sinkers... take a look at this:
View Image
See the nails on the the Simpson post cap? I pulled two of them out with my fingertips. The other two were holding somewhat better. But hey, no big deal right? It's only the one eighth second story being supported on this beam - no big deal.
Edited 6/22/2005 5:22 pm ET by xxPaulCPxx
I was WONDERING how long it would take before someone outed me as a sissy nailer - sheesh, that video's been up for how many days now?Rebuilding my home in Cypress, CA
Also a CRX fanatic!
How many walls could paul erect using conventional code approved construction methods in the length of time his "tests" and this thread has run.
I have been fond of using alternate fastening methods but they are balanced by practicality for the task at hand.