Here are some pics of a jig me and a buddy made to drop axles. It works good. First heres a pic of the end where the spindle goes(an old spindle welded to rect. tubing perpandicular to anther longer piece of rec. tubing.
then we made a index stop to how much we want to drop it, so when the axle is in the jig you measure up and set it at say 2 inches
then on the other end there is a guide to keep it going from side to side and we also made a stop for amount of drop ont the other end so the chamber is correct, and also on some axles we made a stop so the axle would stretch as it was being dropped(bolt into perch bolt hole)
then when its red hot you put a bottle jack underneith the perch bolt hole and start to jack (keeping heat on it moving around) just go slow, if it starts to thin in an area just concentrate the heat in a diff area, just keep going till you get to your amount of drop. then just repeat for the other side. the usauly turn out pretty uniform but are always going to slightly very
well that seems alot less complicated that I thought it would be. How do you make sure both ends have the same amount of drop? I'm not getting the 3rd pic though, is that the same jig or a different one? what does what in that pic?
heres some more left to right 32-36 2-1/4 inch drop " " " " Model A 2-3/4 inch drop Model A 2 inch drop
Whats the lowest drop you've been able to pull off doing this? Jusst wondering how far you can stretch a stock axle.
that aint too tricky at all ! thanks, great tech post , and i might just do it myself....any aussie guys interested in offering up an axle or two? I work in a metal fabrication/forging shop, and reckon i could set that up in an afternoon.
its the same jig just at the other end. So you make a stop at that end also. i know it was a bad pics but dont have camera right know. basically it has a loop that limits how much that end moves and the other end you contol with the jack they just have to both move the same
the most weve been able to drop was the duece com. about 2 7/8 over what they are already (a 4 inch drop isnt realy a 4 inch drop axle they already have a drop built in, so say it already has a 1 3/4 drop and you drop it 2 1/4 you have a 4 inch dropped axle. If you stretch them to far they thin out and get skinny and funny looking ( O I guess like a dego axle)
Could you make one and just use a spindle on both sides? and build some kind of adjustable stop for whatever amount of drop your going for? Couldn't you also make the lenth of th ejig adjustable for different axle lenths? I'm just tryign to think of a way to make something similar that would work for alot of different axles and drops and still keep things where they should be.
the only problem with that is when you drop the they also have to get narrower (some more than others) so i think you can only do one end at a time and this one will do any early ford axle
If you lock down one kingpin hole, then anchor the other end of the axle at a set height, bending the axle like that would cause the camber to go negative...how do you compensate? Do you have it set up so you can simply remove a pin or whatever from the "cold" side of the jig and then lift the axle to spec before it cools or do you adjust them after they cool? Also...how do you verify proper temperature for bending without overheating? How do you go about cooling the axle after bending? That sure is a simple setup bud! Gotta hand it to you! Bill
just thinking. a rod that runs up through the perch hole,welded to the jig, perpendicular to the axis of drop would keep everything in alignment better, the jack could sit just inside the perch pin 'rod' Or does the track width decrease when you do these? If so, how do you keep that aspect even? A bit of 'adjustment' after both sides are dropped?
we let the other end move with the axle till it also hits its stop. the stop on the end you are heating is stopped by the depth gauge and you stop pmping the jack. i guess i dont heat the axle so it drips on the floor! and i let it cool down by itself when it wants to, i dont want to quench it with water because it would make it weak without anealing it
you could do that but it doesnt travel straigt up. Its at yet another angle!!. the track width does get narrower but we put a stop in the perch bolt hole on the end were not heating so it limits the amount it narrows, the usauly seem to act the same way every time so it turn out pretty even but ive never realy measured it, figured a 1/4 wont make a bit of differenc if it even gets that far out!
real cool. i just wonder if it weakens the axle at all. obviously quenching it would make it brittle but would it not be a good idea to have it REheat treated after the drop?? i'm sure they never bothered back in the day but i suppose it could be done for a little piece of mind. way cool tech TITUS. i might try it one day just for fun
Nice Job Titus, I'm impressed by the simplicity of it. I picked up a 32 axle the other day, I might have a go at dropping that one. I remember an article in one of the mags (RnC?) that showed the process used at Mor-Drop. It was similar but the perch bolt area was guided to give a certain amount of stretch. (If I remember right). They also cooled the perch boss and kingpin boss to keep distortion down. How do you get on with kingpin hole size? Any problems? Good post. Mart.
the more I look at this the more I'd like to pat you on the back for pulling out ALL stops and showing just how much IS possible to do home! I have some concerns however... I worry about the effects TOO MUCH heat might have in that high stressed area. In a forge you can control it and keep it even. Might not even be an issue but...it just makes me wonder. Wheres our Metallurgist(sp)!?!? Also...I think it would be an idea to cool the end by burying it deeply in a container of dry sand. That would allow the heat to equalize thru-out the end and then cool slowly and evenly. The old guy who taught me to weld told me to ALWAYS do that with a forged steel suspension part that sees serious heat or welding. Are those axles really heat-treated? Hmmmmmm...??? They should bend to fail, not snap off! Bill
In reply to the concerns of heat treating, I would point out the reliability of tube axles. Surely a dropped beam axle that has been heated and allowed to air cool has to be as strong as a lightweight tube axle. I would agree with idea of burying the ends in sand just to give a little peace of mind. Just my thoughts.
Looks like a rookie here on the HAMB has a good chance of winning Tech Week. I might have to try this. I've got a couple of stock axles layin around. Thought I would never use them. Clark
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