Technical Drive shaft

Oh it was an amazing drum solo on the floorboard and highway 174 lol. Leaving an annual car show where the tradition is to sign the road, i dropped the clutch at 5500 with straight tread polyester tires which should have distributed an awesome amount of tire smoke, but instead hooked long enough to turn my shaft into a drill bit and stick my ass on a trailer

 

I guess I must have been pretty lucky for a long time. I've shortened probably 100s of drive shafts, and changed 1000s of u joints without a failure, or at least a failure because of what I've done. I'm not taking the blame for the guy bending the driveshaft because he drove over something, or the u joint the cross broke after the guy did 5,000 neutral drops for a month.

Maybe its a good thing I'm not doing so many anymore, right? I mean its not that some have been tested at 8200 rpm with 6:88 gears on a dirt track with rubber on the track coming off the corners, or tested on a couple local drag strips. Yep, that guy that puts the u joints in with a hammer and a vice, and cuts and shortens shafts with a Sawzall, and welds them back together on a steel bench with a mig welder can't possibly know what he is doing. Its all dumb luck. Gene

 

It looks like the universal joint broke. HRP

 

I shorten my own, no issues with vibration even with my crude methods.
One thing not mentioned is critical speed, need to know what RPMS you will be turning to know what diameter and material is acceptable for the shaft depending on the length. Critical speed charts are on the net, google is your friend.

 

Big trucks twist driveshafts often, go to a truck gathering spot and ask truck drivers who makes your driveshafts then go there and have a drive shaft made; or ck the internet.