I do a bridge building project with my 7th graders, and each year I need to rip #2 pine (clear) into 1/4″ square by18 inch long strips. Years past I have used the schools 16 inch rockwell bandsaw (dull blade on the saw… ) and it takes super duper long time, I am pondering using my table saw to rip the strips, (with feather boards and push sticks) but I am wondering if there is a better method before I try to reinvent the wheel…
Replies
heres how we massed produced peg stock..
a 1x6 (clear) on edge..blade up fairly high..rip a groove down the center..
lower the blade, and lay the board flat, with the fence a 1/4'' from the blade..now rip 2 at once..with a good push stick..other wise the arrows can fly back at ya..repeat till the 1x6 is unsafe and use another...actually makes a 5/16 or so pcs.
if ya NEED 1/4'' set the fence and flip faces on the first rip on the edge..remove the 1/4 in the center thatway..then lay down and rip the edge off..much safer than trying to rip a 1/4'' ribbon.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Donate a new bandsaw blade to the school?
Actually they kinda need a whole new band saw, the current one should have been put to pasture in the 70s. Now its a mess.
Go to a modeling or craft supply store.
they should have 1/4x1/4 strips of wood all ready to buy.
Mr T
Happiness is a cold wet nose
Life is is never to busy to stop and pet the Doggies!!
My problem is I need a boatload of them, 20 1/4 inch by 18 inch peices per group, and I have 60 groups, so I would need 1200 pieces, and that would get dear quick
Resaw your wood and plain it to 1/4", then rip again, go a little wide and run through the planer one more time, nice pieces of 1/4" X 1/4"
Shouldnt take more than a few hrs.
Rip lattice strips on your TS....
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 knew a guy in Maine who had a Lath saw.
Basically 16 blades on a long arbor spaced 1/4" apart.
One man feeding 2x into it could literally BURY two guys trying to stack the output!
Mr T
Happiness is a cold wet nose
Life is is never to busy to stop and pet the Doggies!!
I LOVED MODEL BRIDGE BUILDING in high school! (and i absolutely rocked at it- colorado state champ '78). my shop is in a state of total disarray at the moment and unfortunately will be for some months to come but assuming things are in order next time you need it, i'd be glad to do it for free. in the meantime, tell us more about the contest- rules, dimensions, etc. i love this stuff!
m
I start all the students with the same amount of materials, 20 1/4" by 18 inch strips, and 6 glue sticks (for a hotmelt glue gun ) they are allowed to trade, but not allowed to bring in more materials.
I also supply them with unlimited wood glue (which is stronger than a glue gun but takes more effort)
Rules for Bridges
Maximum footprint size of 40cm long x 12 cm wide x 12 cm high
15 3/4 inches long x 4 1/2 inches wide x 4 1/2 inches high
Minimum dimensions of 35cm long x 12 cm wide x 12 cm high
12 3/4 inches long x 4 1/2 inches wide x 4 1/2 inches high
Your bridge must have room for a roadway that is 5cm wide by 5 cm high, and 40 cm long.
2 inches wide by 2 inches high by 15 3/4 inches long
Your bridge must weigh less than 150 grams
5.25 oz or .33 lbs.
You will be given a certain amount of wood and not any more. If you make a mistake, you will not be given more wood
You cannot coat the structure with glue
I use a stack of 2 inch wide aluminum plate and a 1/2" eyebolt to load the road surfaces with my homemade very scary bridge breaker.
I will need to post pictures of it. it needs to be seen to be believed!
Jeff
I would like to offer two twists on the previous suggestions:
1) If ripping 1x stock (3/4 thick), getting two pieces at a time, I would avoid having the 1/4" lie between the blade and the fence - too much chance of trouble. I would put the 1/4" on the "waste" side of the blade. To avoid the tediousness of having to move the fence so much, I would start work with many equally wide boards 18" long - say, 20 boards or more. Then you can at least get 40 pc. for every time you have to move the fence.
2) You can improve on this plan immensely by using stock more than 3/4" thick and getting more than two pc. for each rip. If it were me and I were really concerned about cost, I would buy the nicest looking 2x8's I could find and cut them into 18" lengths (omitting any large knots) then rip the edges to form the 1/4" slats, then lay flat and do as decribed above. You'll wind up with a few pieces that have defects, but not that many. If you're set on exactly 1/4" strips then you can only get 4 from 2x stock. But if you use a thinner blade (cheap carbide ones have a kerf of about 3/32", I think) you can get 5 per rip that are .225", or just under .25"
good point. I am thinkin if he was ripping on a bandsaw, a few decimal places won't affect much..
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
"I also supply them with unlimited wood glue (which is stronger than a glue gun but takes more effort)"
JR,
Just a tip for you to your students. Use the hot melt off to the side as a temporary "tack" to hold the sticks in place, but let the bond itself be done in wood glue. Hardly much more effort that way.
Jon
I always suggest using the hot glue to tack things in place, and the owners of the very strong bridges always listen!
Does it have to be clear pine? Could you use strips of 1/4" plywood? You could get a boatload out of a 4x8 sheet. Although I guess the ply might be stronger than the pine..."When I read about the evils of drinking, I gave up reading." ~ Henny Youngman
The kids are building bridges that are way too strong on clear pine, so I would be afraid of what they would be able to build out of plywood! Also I dont like how 1/4" plywood splinters
I've done a fair amount of multi-ripping when making strips for cedar kayaks. While I use three blades to get three 1/4" by 3/4" strips per pass, you can use either two blades to get four strips per two passes. Set the fence to 1/4", then use a 1/4" spacer to set the second blade 1/4" away from the first. Lower the blade below the table, install a sacrificial insert, start the saw, then slowly raise the blades so they cut through the tabelsaw insert. This will give you a zero-clearance insert. Raise the blades to about 7/8" to 1" or so. Run a length of 2x scrap stock through the blades to be used as a push stick. Cut your stock to a managable length. with 20" long finish pieces, cross cut to maybe 40" or 60" long, plus an extra inch for scrap. Run the 60" piece through on edge, then run it through on the flat. Have the face of the board that was against the fence on the first pass against the bed of the tablesaw for the second pass. When ripping on edge, always have the same face of the board against the fence for each pass you make. Don't ever flip the board face-for-face. With two blades and two passes, you'll get four 1/4" square by 60"-ish strips. After multi-cutting on the tablesaw, use a stop block and gang cut the 60"-ish stripa into 20"-ish lengths. With two passes on the table saw and three cuts on a chop saw, you'll have 12 pieces. Do it 99 more times and you're done...
Edited 6/4/2004 11:40 am ET by Mongo
That's a great system.
I'd try and make a push block that went btw blades and btw blade and fence and also held things down. Keep positive control of the pieces all the way through the blade and keep the hands well away.
I want to build a cedar strip project soon and I will use your system.
Steelkilt Lives!
i teach bridge building to 7th graders but i buy 1/8x1/8x36" strips of balsa wood from modern school supplies http://www.modernss.com . i used to rip my own stuff but when i figured how much time and effort went into making small strips i stopped and got the stuff precut.
my kids love this project, and it amazes me at some of the very creative plans that they come up with....we do truss bridge designs....good luck
A lot of good ideas so far. I'll add my 2 cents woth.
I once watched someone create small parts in quanitiy. The general idea was that you obtain or plane down flat stock to 1/4" and then grue them flat ways with bands of hot glue across the grain. How much glue to use will take experimentation to determine and likely will depend on the glue and wood used. Table saw will cut several inches so you should be able to create a thick stack. these could be as long as it practical. Don't forget these are likely to get heavy if too thick or long.
This stack is cut lengthwise using 1/4" spacers to eliminate the need to adjust the fence. The Once you have 1/4" square strips still glued you can stack these in a chop saw with a wide stop to get your 18" lengths.
The glue should come off with minimal effort. Possibly you could use this to hand out the sticks in blocks of ten or so so that counting wil be easier. I would experiment with using a cheap and weak glue, possibly low-temperature hobby style. A putty knife or maybe even the stiff plastic aplicators used for auto body work would be effective. The plasic ones being safer. This final step could be a job the kids could do. They might even enjoy it.