has anyone built their own driveshaft? i come from the 4x4 world all of my builds so far have been 4x4 trucks and there was talk going around about using square tubing for driveshafts this is ok for low speed any thoughts on it for a hot rod? also i need to shorten the existing driveshaft either way how do you balance a driveshaft at home? i have heard about using two hose clamps and moving them closer or further away to balance the shaft ? thanks levi
Let's start with this. I suggest you don't do it at home. Use axiline as a search word, will find a thread I posted in. Also look at some of my other posts about driveshafts. I have been building shafts since 1989 and can do tomorrow if that's the job I need to fill in for the day. My favorite hammer is well worn.
why square? just mark the position so it is clocked correctly, carefully cut away the shaft from the yoke, cut to proper length, heat the tube, re-insert the yoke, weld, and have it balanced. if you throw a driveshaft and destroy the car, you end up spending way more.
Sure you can, here is a link on the HAMB where I show you how to do it. I have had to have very few of the hundreds I have done balanced: http://www.jalopyjournal.com/forum/showthread.php?t=447741&highlight=shorten+your+driveshaft
the theory behind square tube is for long travel suspensions so it will extend a great length, i haven't tried it only heard and was curious about it.
When I needed a driveshaft for my cars, I found a shaft that was just a bit longer, was a constant diameter, and used that. I cut the end that did not have balance weights, or, failing that, I marked where the weights were, and carefully cut them off, to preserve them for reuse. Grind carefully around the yoke, until you can just see the parting line. Pop the yoke off, then shorten the shaft to the length you need. Tap the yoke back in, make sure it's in phase by rocking it on a flat concrete floor. Clue : it won't rock. Then put the whole into the car. Affix a dial indicator to the shaft at the cut end. Rotate and tap to bring it in line. Tacking: attach the ground lead to the SHAFT. Wrap the cable around the shaft a couple times, in the opposite direction to which you will turn the shaft. Tack and measure, tack and measure. Four times at least. To finish weld, you can rotate the shaft in the car using a wheel, or take it out and weld it at the bench. This is the technique that I used, and the shafts were perfect. Cosmo
The theory about square stuff is for low RPM agricultural PTO driveshaft applications like on rotary mowers, post hole augers, etc, where the rotation speed is LESS THAN 1000 rpms and installation is varied by different lengths of 3 point hitch to PTO output locations. The other theory about square stuff isn't a theory. Automotive u-joint size yokes don't have components that are manufactured to accept ag components with one exception that is larger than you will use under a normal car. Demolition derby car and pickup builders fab or hack stuff together to make the unlike components match. Automotive driveshafts spin at 2000-3500 rpm roughly at 60 mph depending on gear ratio--not to include drag car or dirt car stuff. http://www.jalopyjournal.com/forum/showthread.php?t=388458&highlight=patrick2965<<<<<<<<<<<< Take a little bit of time.
you could probably build something like a home made version of crankshaft balancer, 3 rollers on each end, two mounted solid and one with a bit of give hooked up to a set of points rigged to a light, degree wheel on one end with a pointer. heavy side pushes on the roller closes the points, flashes the light tells you where the heavy side is. If i needed to balance a drive shaft I'd give it a try.
Ive done two shafts at home. Both worked great with no vibes. 1st was a jeep shaft. Had fixed yokes on each end and telescoped in the middle. I cut it near the slip section, put it in two v blocks to center it up. Ended up with about .003 runout. The second one had a slip yoke at the trans. Much harder. Cut it at the rear yoke and adjusted for runout with it bolted to the rear diff. I could only get to about .020 runout but it has no vibes either. Give it a try. If you screw it up then take it to a shop. Cal Oh yea, dont forget to phase your u joints correctly.
probably cut 25-30 and have never had a vibration problem. I use the method in the link above, it ain't rocket science.
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