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Does anybody know the calculation/formula for working out how much pipe to heat when making a bend in a pipe packed with sand. I was shown as an apprentice but the old guy who did it was German and hung over at the time, apart from about 30 "f--k der ba-tar-" per minute I can't remember what else he said so it has always been a bit of guess work.Clive
Reply:Not sure of the formuls but make sure the sand is DRY.JimCut an MGB and widened 11" C4 Corvette suspension and LT1 Chevrolet power & 6 spd. Pictures here:Part 1http://forum.britishv8.org/read.php?13,7581Part 2http://forum.britishv8.org/read.php?13,22422
Reply:How well does this work?Me!
Reply:Originally Posted by Me!How well does this work?
Reply:I would think you could bend a tube cold with enough force/leverage.Miller EconotigCutmaster 38Yes ma'am, that IS a screwdriver in my pocket!
Reply:Originally Posted by Joe HI would think you could bend a tube cold with enough force/leverage.
Reply:Originally Posted by wirehuntYes you can, but it ain't going to retain any shape like it should.This is on an aged memory, but 1:3 rings a bell. Funny thing, but an old German showed me....
Reply:I never learned much of a rule other than heat the length of the bend as exactly as possible, and err on the short side. Did a buttload of specialty bends a while back on pipe from 3/8 to 1.5", messed up a couple by going too far with the heat.-- you can't unbend.Helps a lot if you use a mandrel, even a wood form does the trick, though chars a bit.Example:For 2" (approx 2 3/8"OD) pipe return bend going on a 8" radius at the centerline (this is a fairly tight bend for this size pipe, if you are keeping score at home, but not REAL tight. No way to pull this cold, though), he takeup will be about 8"*pi*1.1 (why the 1.1? a little more of the takeup usually comes on the outside where the pipe thins, and this is enough of a fudge factor to allow the finished piece to be too long rather than too short. YMMV) but I would heat about 8*3=24" of pipe and, if needed, heat a little more to finish the bend if needed. For a 45 deg bend (same conditions), I would go with 8*3/4 (since 45 degreed is 1/4 of a return bend), or 6".
Reply:OK...seems like something worth trying...now could someone please translate that into redneck?? The **'s are confusing me!Miller Dynasty 700Miller 350P with Aluma-pro push-pullMiller 280 Dynasty with expansion card Dynasty 200 DXMigMax 215 Enuff power and hand tools to create one of anything..... but mass produce nothing!!! |
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