The Jalopy Journal
Discussion in 'The Hokey Ass Message Board' started by GTO 1, May 1, 2017.
Has anyone shortened a driveshaft - what welding gas and wire do you need?
I used a stick welder.
I use a driveline shop.
I use a pipe cutter to make sure it's cut straight. I've also used a stick welder, but a very long time ago.
Nowadays it's a mig with .30 wire and mig mix for gas. Make sure it's phased properly. Press the end in, make sure it's straight and square, tack a few spots around it, checking it's staying square as you tack. Then weld.
Drive line shops are normally best (Bandit), but a lot of us are do it yourselfers. If you're not taking much out of it, it should remain pretty much balanced. Good luck.
I use a shop also. Average is $150 balanced and new U-joints. Not going to do it myself for that.
I used to get them done for $20 in town, but it seems $100-150 is the going rate these days, and they have to go to the big city, also.
I think I might try to do one myself one of these days. A small one would even fit in my old lathe.
To answer your question, use gas and wire appropriate for welding mild steel sheet to a thick steel forging.
You haven't seen me weld . or to take liberties with a Meatloaf classic, "I would do anything on cars, but I wont do that".
I've had a pipe cutter give me a wavy cut, especially on thin steel like a driveshaft. After doing that, I wouldn't trust a pipe cutter to give me a straight cut. Maybe use a big carpenter square to to get the cut square using a file but damn! It's your driveshaft, man...a pretty important part to get absolutely right....save up to let the shop do it.
Your mileage may vary.
he'll fix you......he'll drive you......but there ain't no way he's ever gonna weld you.......
Should be at least tacked in 4 places in a lathe using a dial indicator,then weld'er up !
Dial indicate what/where...
Did mine for the coupster. Drew Sharpy lines with a straight edge slightly off center so when I cut it (4 1/2' cut off wheel) I could re align it. Did the welding and took it to a shop for balance. Used what looked like a 5/16" washer for a weight. Shop said I did OK. Oh, $60 for the balance, my friend paid $200+ for his new driveshaft, same place.
Got the idea from someone here.
the tube. One way to do this is to put the transmission yoke in the chuck, and the tube in the steady rest.
I've done it but only in the car.
How I did it was to cut desired length out of the rear of the shaft make sure it is square, make sure the yolk is phased correct. Thin cut off wheel will make easy work of the factory weld allowing the section of tube to be tapped off the yolk.
Tap the yolk into the tube leaving a 1/8 gap.
Set up a magnetic base dial indicator wherever it will stay rigid.
Install the shaft with new u joints.
Turn the rear wheel with car in neutral and tap until you get it within a couple thousands and tack
Check again and tap back round if needed. Get four good tacks. Then weld it up keeping as consistent of a weld as you can.
I was told keep within .004 mine ended up half of that.
I removed the factory weight when cutting figuring I'd balance later but don't feel the need to.
Numerous hole shots and not any vibration up to 85 is the fastest I've had it.
There is a good write up with pictures somewhere on the board but I can't find it now.
I've done several that way on my lathe. First thing I do to shorten one, is to mark the amount I want to remove.
Cut it most of the way through at that mark, with a sharp point tool.
Then hack away at the factory weld until it's gone. Then finish the cut with a thin wheel or blade .
Split the scrap piece on the driveshaft end if you have to, to knock it off of there.
You might want to scribe a line before you start so you can phase it like it was.
I tap it together and then spin it by hand and tack it ,with the indicator within an inch or so, on the tube.
I couldn't run the lathe slow enough to weld it continuously, so I would skip around and do about 5-6 weld beads, then skim cut the whole thing.
Usually end up with .003-.004 runout, at the most. Never had a vibration issue.
I would always indicate them before I started. Not uncommon to see .025 runout !
SamIyam did a great tech on it years ago.
Meanwhile here is another thread. https://www.jalopyjournal.com/forum...ng-and-shortening-a-driveshaft-at-home.97513/
We that do all seem to have our own ways. For me, first off I scribe a line from the center of one cup hole past where I'm going to remove the section. This gives me a clocking mark, keeps the yoke in phase. Then part the weld and remove said yoke. You can do this with a small cut off disc and while at it make a weld prep. Be sure not to cut off the yoke flange inside the tube. On the mark I want to remove section at I use a sharp scribe and a piece of paper. Paper has a very clean edge. I wrap it around the tube over lapping one full wrap and very carefully lineing up the edge. Then scribe a line on the edge of paper. Cut with what ever you have close but not on the line and then hand file just to the line. You now have a square end. Mark the tube in 3rd's and press the yoke back in lining up the phase line. Prior to having a Tig machine I gas welded them. Make 2 small tacks on 2 of the 3 marks. Now I start welding on #3 mark and go for it. A gas weld is easier for me to control stack and heat than using a Mig machine on this kind of Joint. A clean flat weld should not effect your balance.
P.S. You'll be way ahead to just send it to a drive line shop and pay the price.
"2 out of 3 aint bad!" Clunker.
Long ago I took a shaft to an old German machinist and suggested that he might cut it in his lathe and weld it there.
He about ripped the ceiling out and said no. The welding current could go through the bearings.
Take it to a driveline shop. Truck shops are good.
That is how to do it right but JD Fikes showed me how to use a ring compressor as a cut guide and cut one off and shorten it back in the 70's and I have done a few that way. They don't always come out with the best balance though.
If you are going to do it your self lay a piece of small angle iron on the driveshaft on the end that you are going to cut and mark a good line down the side of the driveshaft for several inches to he end you are going to cut off including on the yoke. That is your line up mark to put it back together right.
I take a hack saw and just cut though the tube next to the weld on the yoke while not cutting into the yoke that sticks into the tube. Then using the old clamp it down ring compressor as a guide cut the shaft off where I want it and put it back together.
I've done several over the past 40 years but you are still better off taking it to a drive shaft shop and having it done. Most of what I did was fixing a field rig that didn't get driven fast enough to worry about vibrations after the workers had torn hell out of the drive shaft.
Or " a three on the tree ain't bad"
Did mine the same as you, nocero. Mine is within .002" also. It seems the easiest way to go. As good as a lathe.
Local driveshaft shop did my last one for 75 bucks with a new u joint. I have taken 2 hose clamps on either side of my cut and used them for a guide and cut with a chop saw. lined it up and stick welded it together no problem on ones I have done.
Years ago I bought a 60 vette, the drive sheft was butt welded in the middle of the tube! My buddy owns a driveline service so I just have him do mine,
If you need to ask ;
It's best to take it to A shop
It is quite doable though. A few things to watch and make certain are correct. I've done quite a few without issue even with background noises of friends telling me it can't be done while I was doing it.
We did them for the stock cars all the time out of necessity of having to have it immediately. A big Rigid pipe cutter was best for making the cut. Taper the inside of the tube with a big round file. I'd cut the yoke plug off with a diamond hacksaw, go real slow until the cut was established. Clean it up on a lathe. Tap the plug in the tube, check with a machinist square, tack in a few places, check again. All I had was a Lincoln 225 stick welder, did the welds in 4 or 5 segments. I never had one with any balance issues, no vibration even on a 7200 RPM pull.
We had a specialist machining company make our shortened driveshaft for our 40 Willys Coupe. Back then, Henry's Machine Works in Long Beach did the custom work.
A lot of the drag racers from Lions and other So Cal places used this place to do custom machining on just about everything. (in 1964, they did the rework on the hubs and axles for our 58 Chevy Impala to be able to run Buick Skylark wire wheels, excellent work!)
The finished driveshaft product was true, nice looking and it looked like one that was factory built. We had plenty of nice comments from those that scrutinized our Willys build in the Lions pits.
For something as important as a custom shortened driveshaft, there is no way to do it at home unless you have the same tools and alignment tables/machines as a place like Henry's. If I recall from those distant memories, it was not expensive and had to be done right. My brother said the extra cost was going to pay off in the long run, as far as reliability.
I am sure there is a reliable company in your neighborhood that could do the same quality job in less time. That would allow you to spend time doing some other things on your build. IMHO
I use mild steel wire and argon mix. But I have used a gas welder and coat hangers and stick with E-6011 (commonly known as farmer rod)
How does one do a torque tube style drive shaft???
Separate names with a comma.