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Square Tubing for Wishbones
cassidym - 9/11/04 at 08:42 PM

I guess I'm daft but I'm thinking of using stainless square tubing instead of round for my wishbones.

Am I totally off my trolley or is this feasible?


Mark Allanson - 9/11/04 at 08:45 PM

SVA may be a problem if the radii are less than 2.5mm, where are you going to get square bushes from?


cassidym - 9/11/04 at 08:58 PM



The pieces with the bushes will still be round.


JoelP - 9/11/04 at 09:59 PM

ive made two sets out of square tube. both worked, in so far as they didnt collapse when i dropped it off the jack. The later set also survived a blast down the road. Neither were particularily good. Pros, the angles are easier to cut. Cons, i dont personally believe that they are as strong as a similar WEIGHT (not diameter...) in round. each to his own.

my latest ones are 19mm squarem 16g. i would recommend 25mmx2mm if you are using for regular safe use. Alsom make sure that the grade of stainless is good enough for the job, and that you have them designed without any obvious weak spots, as discussed in various threads recently.

all the above is not professional advice obviously... caveat emptor.


cassidym - 9/11/04 at 10:36 PM

Thanx for the advice.

Is it possible that you can post a pic or 2? I would love to see them in the flesh.


JoelP - 10/11/04 at 10:31 AM

you're lucky! i took one before my camera broke...



this is badly designed really, ive learned lots since making this. The shocker mounts onto a 6mm bar. this creates a stress point at its ends, as all the bending wants to happen here, just where it has been affected by the heat of the weld. In its favour, due to the suspension outrigger, the shock mounts close to the balljoint, so the bending force is reduced. I think it will fail SVA on radius if nothing else.

upper bones and all bushes/tubes were supplied by MK engineering.

bloody hell, just noticed a bolt missing from the top of the upright wonder if its still like that!

[Edited on 10/11/04 by JoelP]