Went through 4 bits in under 5 minutes yesterday trying to drill through old steel. I need to get a new set of bits that will work and won’t break the minute you put any pressure on them. Cobalt, titanium, HSS, are they all hype? Any suggestions?
SHG
Listeners write in about removing masonry chimneys and ask about blocked ridge vents, deal-breakers with fixer-uppers, and flashing ledgers that are spaced from the wall.
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.
Start Free Trial NowGet instant access to the latest developments in green building, research, and reports from the field.
Start Free Trial Now
Replies
I buy my bits at an industrial supply house. Those Vermont American and some of the store brands, like Ace are pretty worthless for serious drilling IMO.
Having said that, successfully drilling steel and prolonging bit life is a function of drill speed, keeping the bit positioned firmly (a decent drill press is much better than trying to drill by hand with a portable) and using cutting oil.
A good job-shop machinist can give you a wealth of info about metal cutting and drilling tools, speeds, lubes, bit configurations, etc.
Maybe there was too much pressure ? How big a hole are we talking about ?
In any case, Lee Valley sell good quality bits (I guess you'd be closer to Garrett-Wade ? same stuff), but you can do just as well by finding an outlet that services the machine-shop trade (and there are lots of those near you); and buy a decent quality cobalt set. For larger sizes, just buy loose bits. If you're not using a drill-press, then you don't need number or letter sets. A drill-guide may help you, maybe even a lot.
Drilling steel requires a light, steady pressure; sometimes cooling; and low RPM's; keeping a constant position and drill angle will mean a lot.
Phill Giles
The Unionville Woodwright
Unionville, Ontario
SH,
The biggest mistake I see most guys make is using too fast of a speed. We do a lot of drilling of old exhaust manifold bolts and have found that the best way is in the drill press with a slow speed (100-200 rpm) and cutting fluid. I use CRC tapping and machining fluild that I get at a local electrical supply house. The other thing is not enough pressure which causes the drill to just "slide" on the surface instead of actually cutting. It is almost impossible to get enough pressure with a hand drill unless you have the part you are drilling on the floor so that you can put your weight on the drill and press straight down.
As far as the quality of the bits goes, there is a world of difference. The stuff that the Box stores have is pretty much all junk except for the Dewalt bits. I get most of ours from the Snap-On tool guy. They are pricey, but they last. I also have a $400 sharpener that I use on bits larger than 1/2".
Happy Thanksgiving,
Bill Koustenis
Advanced Automotive Machine
Waldorf Md
Shg,
I once had two of my guys drill 24 9/16" holes in 1/2" mild steel using 2 pilot bits and 1 9/16" bits. The pilot bits were a cobalt, but the 9/16" was a standard Vermont American HSS.
I expected them to break one of the pilots and they did.
The procedure I gave them was;
One guy drills and the other lubes and advises on the verticality of the drill.
Use a pilot bit the next size larger than the flat on the point of the large bit.
Stand with your shoulders directly above the hole.
Press evenly down on the drill so that there is no sideways component to the pressure.
Press as hard as possible with the large bit.
Use a very slow speed.
Keep a visible film of lubricant at the bit end. (we used WD40,) If you see smoke flood the bit and hole and release a little pressure or speed.
Ideally,there will be 2 continous ribbons of metal spiralling out of the hole. If you're not pressing hard enough, there will be individual big slivers coming up. If you're going to fast, the slivers will be tiny.
Ease up the pressure and the trigger (keep the same speed) as the bit exits the bottom of the work.
If, when exiting, the bit bites in and stops, back the bit out of the bite with a reverse twist, use the highest speed you got and very slowly ease the bit back down. Be prepared for the bit to chatter and attempt to grab. keep your muscles under tension and compression (think isometrics) so the bit can't grab.
They did good, after 24 holes the bit was still very sharp.
SamT
How old was the steel? It may have had a lot of impurities in it. Depending on how thick it is, (angle iron, plate, etc) can be drilled with HSS and cutting oil at the right speed. Snap On makes a wide variety of bits for different applications or you could look for a place that sells to machine shops. Just about any place that sells industrial tools should have something you could use.
"I cut this piece four times and it's still too short."
you covered pretty much what I was going to say.More bits get burnt because of too little pressure. Bits last much longer when they engage the material and cut instead of skating across it. If it just spins it builds up friction and overheats. Once the cutting edge overheats it looses its hardness and rounds over and temper causing the edge to spall off as the bit vibrates.If you catch this early enough you can easily resharpen the bit. The longer you let it go the farther the heat goes up the bit and the more metal has to be removed. In production jobs it is best to have three or four bits sharp so at the first sign of one getting dull you can go to the next sharp one.In practical terms having three bits will allow you to drill many more holes with sharpening than three times what one would do. Learn to sharpen your bits. You can get a 'Drill Doctor' or such or take them to a sharpening service but learning to do it by hand on a simple grinder, side grinder or belt sander in a pinch, will give you a skill and a lot more options. Buying machines is fun but makes you poorer and sometimes dependant. Learning skills makes you more valuable, adaptable and independent.You can use WD-40 as a coolant and cutting agent. A cutting agent decreases bit wear and gives a much smoother finish. Anything is better than nothing. Dark, sulfured, cutting oil is better on steel. CRC, and many other companies make good cutting agents. My favorite for small jobs is 'Tap-Magic'. Get the regular stuff for ferrous metals and the aluminum version for aluminum. Only down side is 'aluminum Tap-Magic, and most other engineered cutting agents, make it harder to get a good finish bead if you intend to weld it. A solvent wash helps but aluminum is porous and the difference is still noticeable.For aluminum you can try Crisco. We got better weldability with it. In a commercial machine shop setting use of water-based sprayed cutting agents is a solution but not one easy to put to use on small jobs in the field.
4Lorn1,
Crisco, hunh? What, just put a dollop on the target and drill thru it? Does it flow into the hole or do you have to pull the bit out to relube it? Once I find that sweet combo of speed and pressure, I really hate to mess with it by stopping.
As to lubes, anything is better than nothing. I've used motor oil, 3-in-1 works good, alcohol works but evaporates too quick, even tried water, but you got to push way too hard. WD is pretty good and best of all, available.
Never tried water and detergent, though.
SamT
In a machine shop we had spray nozzles that would feed a steady supply of water based cutting agent directly at the cutting action allowing near continuous drilling to any reasonable depth. Alternatively a jet of cutting oil or fluid with be shot under pressure on the action. This balanced the friction of the cutting and heat generated and the heat carried off, or boiled off, by the cutting agent.In the field the best you can do is dip the drill bit a and back off once in a while on deep holes to allow the bit to cool a little. It also clears the hole to prevent chips from backing up. Also this allows the bit itself to act as a heat sink making up for the lack of the continuous cooling action of the fluid. A squirt into the hole when you resume helps.I liked the spray units. They were simply a tank to hold the fluid that operated like a atomizer so the fluid was picked up by the compressed air jet. WD-40 is OK. As you say anything is better than nothing. On hard steel or stainless it sometimes helps, assuming the drilling is on something you can drill down on, to use a rubber 'O'-ring or modeling clay to form a ring around where you are drilling. This is filled with fluid effectively flooding the operation.Soapy water can often be used profitably. The soap lessens water tension allowing it to more fully contact the work and bit and absorb more heat. A simple spray bottle or 'bent pipette' lab bottle works well. Water is cheap, readily available and a lot less likely to stain a customers carpets.On cast iron lard works well. Regrind the bits to a lower angle. Makes the work smell like frying bacon. MMMMmmmm ... bacon.
hey - did you check on the bits today? - - I gotta new/old drill press and have been considering treating myself to an index - - 'tis the season, 'n all that... - -
do they mail order? - -
"there's enough for everyone"
I did stop by my tool supplier today. The 15 pc is .........45/49, there is a 29 and I think it was 89 david. I did not call walter gogel and co. but can do that monday for you if you wish. Maybe scott can give us the name of the supplier that had 'em for 80 even. I know they'll (electrictool) send em, would imagine a charge but can ask tomorrow if you wish.Remodeling Contractor just outside the Glass City.
Quittin' Time
The seller is toolempire on eBay. He has 15 pieces, 29 and a really big set for 250+. The 29 piece set is 85 and change shipped, and it appears that these are the real magnums that Big Cal was talking about.
SHG
"On cast iron lard works well."--4lorn1i dont mean to nit-pick, just curious, but: I had a boss once who used to be a machinist and he allways told me that cast iron was self lubricating, i've had others tell me this as well. .
-->
measure once
scribble several lines
spend some time figuring out wich scribble
cut the wrong line
get mad
Cast iron is a lot easier to drill than some other materials, but that's not the same as saying a lubricant won't make it even easier. I've machined cast iron both dry and with lubricants, and the lubricant does make a difference. It also provides some cooling and helps keep the chips together. Cast iron chips tend to be small and dusty.
Get out the 80 grit jalapeno KY jelly. Oh, sorry. Thought it was a different kind of thread.
"I cut this piece four times and it's still too short."
>> ... 80 grit jalapeno KY jelly.It's amazing what you can find on the internet. I've come across a couple of references to the use of chilis in ... ah ... coercive interrogation.
CI is cake and pie...
Self lubricating too...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Crisco? I'm betting Andy has some right next to his jar of vasaline. The only thing I can't figure is how he can use it in his shop when he keeps it next to his bed.
Not that there's anything wrong with that.
SHG
SH,
Just wanted to add something ... you said you were drilling "steel" ? A lot of guys use that word generically for a lot of metals. If the piece you are drilling happens to be cast iron, it is very abrasive and a lot harder on drill bits. Takes even more care to drill it.
Bill Koustenis
Advanced Automotive Machine
Waldorf Md
Man, you got that right..I have had the same set of Dewalt bits for 5 yrs..only ones I break are under 1/8" and that is me being a jerk.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Scott, I have the Magnum index. A light bronze colored bit. I am most satisfied with this set, the price and cutting. Course, they're new. If you can find them, I would buy a set.......or the size you need and see if you like 'em.
US made.
Jobber Length Drills
Consolidated Toledo Drill
Features:
Jobber Length Drill Type 190-AG Magnum Super Premium: Special Hi-Molybdenum tool steel. 135° split point for fast penetration
and accurate starting without a center punch. Precision ground point, flutes, body, clearance and drill diameter for the ultimate in accuracy
and performance. Body and clearance are gold surface treated for maximum lubricity. Drills are heat treated at 2185°F. and then nitro-
carburized and finished at 950°F. to be measurably harder than high speed steel. Space age nitro-carburized steel withstands substantially
higher drilling temperatures while maintaining sharpness. Recommended for use in work hardening grades of stainless steel and other hard
metal drilling applications Sizes smaller than #52 have non-split points.
Remodeling Contractor just outside the Glass City.
Quittin' Time
So here's the details. I was drilling 7/32" with WD40 lubricant into my 64 Austin Healey to install aluminum door pillar covers, using first HSS, then titanium bits. Each of the 4 broke. I probably used too much pressure, but had no smoking, because the suckers were not going through the sheet metal (this was before the days of fiberglass bodies). I was trying so damn hard to get everything perfect, because I love that stinking car. And the bits kept braking, as did my heart. Didn't have any problem with skating, as it went through the aluminum first (like butter) and that held it in place. I was doing it by hand because the car doesn't fit in a drill press. Don't see that part changing any time soon.
I now realize that I need to figure out how I can get into the local garage and borrow all his snap-on bits before he sees me. Lawyers don't get a visit from the snap-on man too often.
How are you Cal? I'm going to look for the Magnum bits. Happy thanksgiving to all, and thanks for the help.
Scott
Not that I can tell, but there are a couple diff cutting angles on bits. Maybe move to the next angle. That's a fairly hefty bit to be breaking if I did my math right. You chuck it up short?
We're good scott. Been laughing a quite bit with all the crap that flies through this site lately. Especially like the feet in the mouth from the new members.
Sun beaming today, ready for football and the bird.
Sports around here suck, but the cavs are giving it a go.
Work looks good, should be busy till spring.
Been waiting to buy you a couple, you never go west?
Best wishes up through the holidays.Remodeling Contractor just outside the Glass City.
Quittin' Time
Scott,Drilling through anything at all on a car, seems to always be problematic.Did you start with a pilot hole first ?Try an 1/8" pilot hole first. Hold the drill very steady.As others have said, slow the drill down. It seems logical that really pushing, and running that drill at the highest speed would get the job faster. But logical or not, a slower speed is better. And while good pressure is important, a steady hand is even more important. ESPECIALLY on cars...
The person you offend today, may have been your best friend tomorrow
Since the holidays are near....years ago I was working out of town and needed some bits. I headed to the local hardware and noticed a set of a dozen on the bargain table, you know the one, a pack of wood chisels for a buck, magnets, stuff like that.These bits were made in N.Ireland and meant for metal, I was drilling wood for inserts and they were incapable of drilling cheese. Borrowed a drill bit and chucked the whole pack into my truck box. After much soul searching I gave them to my brother for Christmas, next year he gave them to our dad, and they are still out floating around the distant family. Anybody ever have any luck sharpening the tip on uni-bits?
<<Anybody ever have any luck sharpening the tip on uni-bits? >>Yup, just kiss the flat witha dremel or a small angle grinder wheel Do NOT try to adjust the bevel of the first 'lobe', just de-burr it..lightly. I have always used a pilot for the larger one, and the small ones are dull from the git go..BTW @ 50bucks for the the bigguns, don't overheat them.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
I'm wondering if you are trying to drill through, or near, a weld. If so, you can expect to break bits. As others have said, go slow and use fluid as a coolant.
Have you seen Bullet Point bits, by Black and Decker? A variation is sold be DeWalt. They are like a brad point bit in that they cut on the outside first and have a pilot point in the center. I was trying to drill into some angle iron last winter and wasn't getting anywhere with my Titanium Nitride bits. When I switched to the old (literally) Bullet Point bit, it cut right into it. I have used these for years, starting when I was still doing 12 Volt car stuff. I got tired of burning through drill bits and tried them. The only other ones I liked for going through sheet metal and steel (less than 1/2" thick) without using a drillpress are the cobalt bits. If the bits are breaking, either they're grabbing or they're being side-loaded, which makes them try to gyrate. Hardened steel doesn't gyrate well, it breaks.
"I cut this piece four times and it's still too short."
Youre not going to tell us you bought the bits at Home Depot are you?
Although I do have to say in your defense...where else can you buy anything around here other than the lumberyard or hardware store. All the same crappola.
Lee Valley is a great resourse if you have time to wait.
Going to HD for anything quality is like telling me to use phillips screws on the door hinges in my old house...lol
a
The secret of Zen in two words is, "Not always so"!
When we meet, we say, Namaste'..it means..
http://CLIFFORDRENOVATIONS.COM
Actually, I started with a set that my father in law had given me for Christmas a while back. Cheapest crap he could buy, god bless him. Then I went into the hamlet and bought some titaniums. Then I went back to the hamlet and told him I wasn't satisfied (100% satisfaction guaranteed, you know) and got another set of titaniums. I didn't have the nads to go back again.
I found those Magnum bits that Cal was talking about on eBay for $80 for a 29 bit set. Pricey, but if they last, it's worth it. My last thought was chugging over to your house and seeing what was lying around the garage. But I can't keep getting my tire fixed either, so it seemed like a no win situation there. So Cal, is that a good price for those Magnums? http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=4507022606&rd=1&sspagename=STRK%3AMEWA%3AIT
SHG
Edited 11/25/2004 2:35 pm ET by SHGLAW
I worked for a guy who is one of the cheapest people on the planet. I was drilling a hole in a car and behind the surface, there was another part that was on an angle and my bit snapped. He said he just got some new titanium drills and I should use his. I wanted to test it and drilled into a 2x4. The drill must have caught a knot or hidden screw, because it bent in about a 90 degree angle. I took it out of the chuck and, with my bare hands, straightened it so I could put it back in the index. I went out during lunch and got more cobalt bits.
"I cut this piece four times and it's still too short."
Shaggy...am I to kill you today of mbnext week dickhead?
Not one person ever got a flat tire here...ever. If you did it was probably because Moses felt you were in the need...lol.Ayway....sucky dinner tonight at the restaurant which will allow me to appreciate next years dinner here.
Hmmmm. I have a separate mail I just might send you concerning a huge expensive kitchen I ordered due on Jan 10th,,,,and they wanna charge me $400 for "paper work" to change the hinges....simply a different color...they say the $400 is for paperwork....My head is about to explode...hey..that might be a good thing...lol/////seriously though....I'm about to loose control in a sense....I've basically ordered two kitchens worth of cabs for my kitchen and theyre bustin my ballz over a hinge change that hasnt been installed yet?????I'm so ready to deal with this chaza rey you have no idea!!!
Be well bro
andyThe secret of Zen in two words is, "Not always so"!
When we meet, we say, Namaste'..it means..
I honor the place in you where the entire universe resides,
I honor the place in you of love, of light, of truth, of peace.
I honor the place within you where if you are in that place in you
and I am in that place in me, there is only one of us.
http://CLIFFORDRENOVATIONS.COM
send me an email and we'll deal with them.
I had to drill a couple of dozen 3/4" holes into some 3/8"
mild steel(angle iron)......
bought one of those titanium stepped uni-bits...
worked way better than I first thought it would....
stayed sharp, didn't catch like a twist bit would have...
way safer ...... highly recommended
regards
oh man, chocolate pie.............
not fake, no pudding, real crust.............
ok, back to bizness. I bought the 190AG SP-15 Set Super Premium. 44.95 from my boys at http://electrictool.com/.
So, maybe the 29 is good, tho I find it a bit confusing for me unless I'm tapping.
I could call them tomorrow morning if you wish. I've had the set since 7/9/04. You know how much steel I drill. But, what I've drilled, I like em.
A machinist showed me once a set that had a weird twist to the bit, like a barber pole, not near as steep as a reg twist drill. Those bits were very good. He'd touch em up on a grinding wheel. McMaster Carr comes to mind. Confusion starts here: http://www.mcmaster.com/
I'll give Electric Tool a call tomorrow morning and post here.
Remodeling Contractor just outside the Glass City.
Quittin' Time
Edited 11/25/2004 7:58 pm ET by calvin
Hey calvin, just a heads up. I don't know if you are familiar w/ Walter Gogel's or not. They are downtown, have the same bits, and you can buy any quantity of singles or bulk. Just went down last week and got 12-packs of all the smaller sizes ( under 1/4" - the ones that always get lost or broke ) They are industrial supply house - saved lot o' cash!
SHGLAW, don't know if they're online or not - could try a search for Walter Gogel Co.
yessir, walter f gogel. Good place for hardware and I guess I now remember bits too.
You from Toledo? Some of us locals get together for a beer and BS on occasion. What's your area of expertise?Remodeling Contractor just outside the Glass City.
Quittin' Time
I'm over in Oregon. 12 years general remodeling, 5 years building new homes (chasing money that wasn't there) , back to the good, fun work now. Work mostly alone but we have a little network over here where some of us little guys pitch together for bigger stuff.
Beer and BS - that IS my area of expertise !!!
You know dave richards, drywaller extrordenaire? He's an Oregonian.
I'm in Maumee, also solo. Work your way rarely. Seems like halfway across the country. River crossings and RR tracks make it a trip. Email me here with your number, I'll stick it in the van and give you a call if over your way. They ever raise the speed limit within 5 miles of your HS to anything over 25?Remodeling Contractor just outside the Glass City.
Quittin' Time
I have some of what you were struggling to think of..a high helical twist bit..awesome. They tend to self feed , so ya need to be careful, and they also break religiously..but man, what a bit.the high helical shank allows more "bite" and feeds the shards out faster..they will cut ya when the don't wad up around the shaft..they sling like a pinwheel...dangerous at best.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Yes to all. I have a "short" 1/4".Remodeling Contractor just outside the Glass City.
Quittin' Time
I don't know.
I bought some tubing Christmas lights there that were...well...ok.
You're broke 4 bits almost 1/4" in diameter? Yeesh, that's either some crappy bits or you're stronger and aiming wronger than you think...
I like the idea that you're hitting a weld...makes sense. The only other thing I can think of is that you're hitting hardened steel, but that's hardly likely in that car.
I'd use a real cutting oil, like a tapping oil, rather than WD-40.
I'd also use a carbide-tipped bit. I've got some nice Joran bits where the carbide tip is seamlessly integrated into a normal twist bit, rather than the typical looking masonry carbide bit. The bits are meant for drilling nearly any material, and handle like a regular twist bit as opposed to a masonry bit (don't skate as much, etc).
Joran is, I believe, a subsidiary of Irwin, but darned if I can find Joran anywhere on the web.
Regards,
Tim Ruttan
fer you..
US, Swiss or German made...
M2 steel...
Drill with constant speed and pressure.... fer the whole hole....
use wax or oil fer lubricant.....
what are you drilling???
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
what are you drilling???
my Healey. I drill with love, and can't be responsible for the pressure.
Scott
loose the WD-40 for lube....
wax...
same pressure all the way thruu...
small piolet hole first perhaps....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
I saw the cd, Marty. That's some helper you have. Now I know why you don't need the wd-40 for lube. By the way, the bear commercial is a huge hit with my son.
Wax? Andy uses crisco. But he didn't say what for.
Scott
Edited 11/27/2004 7:21 am ET by SHGLAW
FYI, Drill bits do not suck.
vacuums suck
babys suck
calves suck
But drill bits do not suck.
point well taken