bending cast iron

[Goofour]

I need to bend the arm on a auto spindle about 1 inch. can this be heated and bent?

[HuFlungDung]

Its most likely not cast iron, but steel. If its cast, it will let you know right away by cracking off

[sendkeys]

I think HuFlungDung is right and it's steel. Almost all that i seen are even very old stuff. So i dont think you will have a problem. Just remember to let it cool slow as it can. dont dump water on it Would suck to harden it and have it break running down the road. Much better for them to bend if they get overload

[JEFFY]

Most spindels are steel, heat it up and bend and let it cool slowly, don't qwench it!
I have done it several times in the past for race car projects, all where GM products.
An inch is a lot to bend on a arm thats only a few inches in lenght, we would weld extra mounts in the spot we needed. Also note that you may be able to find a spindel that has a bolt on arm, these arms are a lot easier to work with somtimes.

[ViperTX]

Come on....you need a matched pair....buy some dropped spindles...much cheaper and safer.

[Hobbiest]

Originally Posted by ViperTX Come on....you need a matched pair....buy some dropped spindles...much cheaper and safer.

Usually this kind of a modification (in my hot rod experience at least)has more to do with steering interference. As stated above, heat the arm cherry red with a rosebud, bend slowly, air cool. For best performance, try to match the origional orientation between the hole and spindle shaft. As also stated above, dropping the arm will shorten it, relative to the amount of drop, and may change steering geometry. Be sure to keep your ackerman geometry (type into search engine), and if safety is a concern to you, have the spindles magnfluxed afterword. BTW...what kind of a spindle is it? My experience is with early Ford parts. Good luck.

[Goofour]

Thanks for your responces I am trying to use S10 spindles and brakes on a Triumph Spitfire that I installed a 350 chevy motor in. I modified the controll arms to hold ball joints but I was having trouble with the bump steer because the tie rod arms had to be shorter. Bending the spindle arms outward should fix that.

[JEFFY]

HE DID NOT SAY HE WAS DROPPING IT! Just for your info, he said he was wanting to bend or adjust the arm. Its not uncommon to have to adjust the arm postition after some form or another when you modify for racing or off road, also for your info on oval track in not uncommon to have differant spindels on the left and right sides. For off road where a higher ground clearance is needed and done with a lift kit, the steering gear is stiil on the frame and now with the height differance sometimes you have to adjust your arms and linkage to get the wheels to turn in there proper arcs(ackerman effect)
FYI: never broke a spindel after any of the mods that where done to several differant spindels use in dirt track racing in 25 years

[Goofour]

Here is one more question I was thinking of using a larger tie rod end but the arms on the rack are 1/2" Would it be safe to weld a thicker bolt on the arms that will fit the stronger tie rod?

[JEFFY]

Originally Posted by Goofour having trouble with the bump steer because the tie rod arms had to be shorter. Bending the spindle arms outward should fix that.

Take a look at the pivot points first, a general run of thumb is the top ball joint and bottom ball joint, draw a line between pivots and the ball of the tie rod should fall in this line. The inner pivots should be the same, then try to get the tie rod linkage level with the control arm it close to. The lemght of the tie rod assembly should be at the two lines, GM generaly has there point match the lower control arm, take a look under a S10.
You should also look at you old spindel arm height, as bump is more tied to a differance in arc pivot heights.
Try the arm as is but with some washer on fitted to the taper of the rod end to raise the pivot and check for bump, if the bump decreases thats the way you move it(the washers are for bump test only)

[Goofour]

First try failled. The arm is about 2" wide and 1" thick after heating it didn't stay red very long but it did bend. After the second try it cracked. Am i not getting it hot enough or did I bent it to far? (1" was easy I was going for 2")

[HuFlungDung]

You may have not had it hot enough, over a wide enough area. You don't want to force all the elongation to occur over a 1" width. If it is a severe bend, you might want to hammer it firmly (only while it is still red hot) to improve the grain of the stretched area. Then, bend it a bit more, if necessary. Use a good sized hammer, you want to dent it to show some indication that you are moving a few molecules around.

Maybe it is cast iron, or malleable iron, which resembles steel up until the time you heat it, after which it reverts to cast iron again. There's no cure if that is the case.

Did you try a spark test? Just grind a little bit of the part's corner on a grinding wheel to find out if it is cast iron: dull red sparks, low in number, indicate cast iron. Compare that to a known piece of steel, which sparks quite bright orange, large volume of sparks.