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MG Midget and Sprite Technical - DIY/ modificated Anti-roll bar
I've still got standard ARB (!) because the very front of my 'chassis' rails are twisted so the bar hits the tyres on full lock & droop. So my plan is to chop a bit out of the middle & sleeve weld it back up with a tube on the outside (like in the picture)
That should make it stiffer, but I don't know how much by...
Is this a silly plan? I don't want to spend 50 odd quid on a bar that's going to hit the tyres when I can possibly make a stiffer one. And I don't want to try straightening the legs as everything geometry-wise is good as can be at the moment (the twist is in front of the wishbone mounts)
I've currently got the ARB set like this /_/ so it doesn't hit the tyre on the right (from the front)
Only issue I can see is the welds not being strong enough to resist the twisting, and not being able to tell how strong it is :s
what do you think?
|NO NO NO - repeat after me|
I must not weld the middle of my swaybar as I know it will break and hurt me
|I think William is referring to the stresses that would be set-up by an abrupt change in cross-section on the tube - this is compounded by the welding that changes properties through heat cycles and so on.|
You'd be better off bending the ends of the tube so they don't contact... and better of still straightening the chassis. Or maybe re-centering the bar to find more space...
|Don't weld the old bar after cutting it Rob|
Attempted suicide to rely on spring steel that has been cut and welded
It'ld be better to take it off completely, drive carefully and fix the chassis soon
Taking it off won't cause the end of the world, the ARB was a maker's add on at first
I had a drop link fastening fail in France and drove all round Normandy and up to Calais, then home before I could get the proper fixing. All in completely stable safety. I just disconnected t'other side and held it up off the road with a large cable tie to keep it tidy
|well, i'm pleased i haven't done that then :)|
I did think hum maybe not a good plan - hence the post on here and not doing it straight away...
if I was to try bending the ends in, is it best to just grab it and bend, presumably heating will make it go 'funny'
thanks for keeping me safe :p
|Rob, the bar is spring steel, you won't bend the ends in without heating, if you did overcome the material resistance and actually bend them you'll probably fracture the metal and have a failure anyway. If you want to bend the bar ends inwards, then heat them cherry red with an torch and then have the bar retempered at a spring shop. I did that to make the light weight bar on the rear of my midget and it worked great. It might be easier to either lengthen or shorten the end links a bit to remove the interference. Usually that will get the angle of the bar to where it won't contact the tyre.|
I did something similar for the rear ARB of my Sprite but after heating to cherry red in various places to re-shape the Vauxhall Chevette rear ARB it could be bent far more than it would see in use without taking a set so it was used as is and I've had no problems with it in over 10 years of use. Obviously bending of the front bar may not go so well, depends on the material and how much it's stressed in use. I'd correct the front chassis leg issue.
|thanks again - looking at it more closely it looks like I might be able swap the drop links round from outside to inside to get a bit more clearance - I'll try that this weekend. Presumably a heavier bar is the same length just thicker..|
This thread was discussed on 18/01/2011
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