Heat and bend a drop axel to get it in line?? really

Top of both wheels are tipped in on the axel i;m using on the 31 coupe..... The dropped axel is what seems to be from an old truck ... Is heating and bending the way this is corrected ???? Thats what it says to do in the old hot rod building book ,, but also says to find a pro to do it.......Is there people at the aligment shops that still do that??? Or when I call are they going to tell me " we have;nt done that shit in 40 years" ....

Can I do this myself ?? we do have torches that will heat an axel.... If there are others that have done this ,, a little help with some direction would be great like chain the ends to the floor , heat and jackit up in the center....or is doing this stuff going to really screw something up if you don;t know what your doing Let me know.......

 

Truck shops do it. They did mine cold

You can do it yourself. I will next time
The "professional" chained my axle down in two places with a 25 ton jack in the middle. Jacked it up, used an angle finder to get it right.

Heck I can do that. No need to pay someone else!

 

Depends how much you need.
Small adjustments are done cold.

 

Bend it cold. I used to do this all the time when I was running oval track 30 years ago and still do today.

Get a steel I-beam about 3 feet long. Cut a hole through the web at each end. Big enough to snake a chain through. Good high tensile strength chain. Not the stuff ya' chain Rover to the dog house with.

If the camber is off equally from side to side, this is what ya' wanta' do.

Jack car up high. A pair of portable car ramps might be high enough. I used to run the car up the loading ramps of the trailer. Lay I-beam under axle on shop floor.

Run chains through I-beam and around axle on the outside of the radius rods. Be smart enough to not run the chains around the tie rod.

Center a bottle jack or porta-power between the axle and I-beam. Make sure the chains are equal length.

Start pumping on the jack and watch those tires move!!!! Because ya' centered the jack and are using equal chain length, both axle ends should move the same amount.

Usually ya' have to go about double the amount of the what ya' need with the jack. When ya' release the pressure, it'll spring back a significant amount.

If ya' didn't go enough, jack it again. DON'T go too far!! You'll be surprised at how little force it takes to bend the axle. Watch what you're doing and ya' won't get hurt if the jack pops out. There won't be that much pressure on it.

On today's roads zero to +1 or +2 degrees camber is good. Radial tires like being close to zero.

By changing the location of the axle jacking point and chain location ya' can bend just one end of the axle. Ya' might have to cut more holes in the I-beam. Running oval track we'd run negative camber on the RF and positive camber on the LF.

This stuff isn't rocket science. Most folks think ya' have to have special equipment to do this stuff. An $8 angle finder and a tape measure is all ya' need to set-up a straight axle front end. To set caster ya' need a torch to heat the radius rods. That'll process will be covered in our next class.

Guys in my oval track vintage racing club have asked me if I have a press to straighten front axles. I'll say "press???". I can straighten it without even having to take it outa' the car. They were amazed at how simple it is.

 

Oh yeah, I forgot.

After ya' get done you'll have to reset the toe-in. The axle movement will change that measurement.

 

We heated it today and bent it back to 0 ... put it up on center stands (inside the hair pins) heated it at the curve of the drop axel...got a big bar and was able to get it hooked under the lower shock bolt on top of the axel and pulled it down to o...looks perfect..... I hope we did it right ??? we used heat was that ok????? DAN

 

You should not use heat. Heat will cause localized bending of the axle where the metal is hottest. To correct straight axle issues, the bends should always be done cold. That way the entire axle will be at the same temperature, and the bend will be spread over a wide area. The only time heat should ever be applied to an axle is when it is being intentionally "dropped" and a jig is used. Hope you haven't just ruined your axle!!!

 

I had an old Mordrop axle on a roadster I built about 10 years ago and it had a real bad camber promlem on the right side, the Front end shop I used put it on the front end rack with the gauges on it and heated it with the weight of the car on the wheels, they heated it where it was originally dropped and it came right into speck, it was awesome, I thought the axle was junk at the time

 

Man, I'm not knocking your knowledge.

As a matter of fact, I have NONE on this subject. This thread is a learning experience for me.


However, I have a question about the logic of what you wrote.

My question is this:

How can it be bad to heat and bend an axle when its OK to heat and bend it when you "drop" one?

I see absolutely no difference. Providing the guy heating his in this thread did NOT quench it with water.

 

NO , I did'nt quench it after heating and bending it back I just let it cool on its own..... Thanks guys for your input..only time will tell if we did it wrong... If (in the future) we do develope issues because of the way we did it ,,I will surely in hamb fashion advice the group... thanks DAN

 

I guess I don't understand the problem with heating the axle, as long as you don't quench it and let it air dry. I just had loudpedal heat & stretch my I-beam 3" without a problem and that's between the perch & the spindle where the leverage would be the worst, not between the perches. How can heat and a little bend in the center of the axle be any worse ???
Looks like we need a little input from the HAMB Metalurgist................

 

Heating and bending is Ok IF you know what your doing, it's alot more than "gettin' red reefin' on it and let it cool". The heat must be distributed over a wide area with more in the area of the bend, the heat needs to be maintained during the bend and after while checking the bend for correctness.
Most car builders that I know then bury the axle in sand for a slow cool down.

On the other hand, the adustments done by the dealers and the truck spring shops on the old straight axle cars and the current big rings is done cold using jacks/rams/jigs/chains, etc..

 

WOW...Rockinrods... Who pissed in your coolaid????? That was definately uncalled for..... There was nothing in his post that even came close to out of line..... WHat's up???? Did you actually read what you quoted before you started calling him an ASS HOLE? At least he had a good question, and didn't just come to call names......