My take on the Titus axle dropping jig.

I agree with stressed out and others on the need for additional structural reinforcement and a hydraulic ram instead of an air cylinder.

I see two potential areas of concern -- the need to concentrate heat in the stretch area, but also over a broad enough area to stretch the stretch over as much of the beam as practical/possible to avoid cracking or thinning in the stretched area. Did I say that right? My concern is that in doing this, you don't elongate or distort the king pin bores.

I also envision the need for a beam or structure under the axle which connects through the two perch bores wherein this beam would then be lifted by the hydraulic ram at one end. Placing a level on this beam would afford better control of the stretching operation to maintain the proper angular relationship between the king pins and the axle beam and perch bores.

The axle may tend to want to pull in the direction of the spindle which isn't the worst thing if you can replicate the action on the other side. This assumes you are stretching one side at a time. The axle may also want to dip at the other end and the beam thing with a level attached might allow you to see this happening and correct it.

 

Ignore the pics of the old one above. The new one has a base made of 10x10x1/2 grade 65 tube, with a piece of 1 inch plate welded inside it as a vertical rib. The old one worked just fine, but when I decided to use a round spindle, I just rebuilt the whole thing.

Edited to say, I have ran the whole thing through Ansys 9 Workbench. It's FEA software, and my jig is good for 3 times the load my 30 ton cylinder can give it, and it doesn't take 30 tons to drop a heated axle, trust me. Roost, I'll bet you a bud my tube with the internal plate is stronger than that I beam, hehe. Axle jig rivalry, hehe...

 

any pics of the new setup...

i can't belive it's been that long ago......crap, and i still haven't started one!

 

i have seen one of these jigs a freind made and his has all sorts of guides and pointers and stops to insure acuracy every axel he drops comes out perfectly the same... due to these parts i dont see on this tool.. he has diferant chucks to do differant yrs and amounts of drop

 

No pics of it right now, it worked great until my porta power blew a seal. I've been to lazy to repair it, so the jig sits. I have been "advising" a couple other hambers on their own axle jig builds, so there are other ones out there. If you design the fixture right, you don't need boat loads of guides and pointers to insure accuracy, the way this jig is designed, it's all built in, and trust me, every axle is uniform in it's drop. I'm getting tired of explaining to everyone here how this works, and then being criticized on it's design(which I didn't even come up with). Doesn't matter though, because I'll never drop an axle for anyone else, just in case it would break,lol...

 

How do you measure or keep track of how high the "other" spring perch boss raises? As raising one higher than the other changes the camber on the axle.

Sam.

 

I don't see how it could be more simple, you've described it very well in my opinion. I may do one of these someday.