Just thought I'd show u guys some damage to my bottom wishbones made Exactly as per the book!!
Only thing I remember hitting is road works old tar to new ramp...

If anyone is making their own parts like me.. i would strengthen the books design.

Cheers J



Sid Hat

Sorry for size...


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Hi Mate long time no see. Looks quite bad though not a complete fail! r u going to remake new ones or buy a set of prefab from a company?

Cheers

Brian

Looks like not enough strength in the plate the suspension bracket was fixed too...

Looks like you've got about 30 seconds to get those off the kitchen worksurface before you get shot mate... Many design incorporate a 90 bend at the edge of that plate to resist the bending and then plastic deformation you have there... Is this what you were telling me about at Ingliston??

Cheers

Yo.. hi Brian.. No not making new ones, gona repair these and strengthen them as per James's comments.

Ben my point is that they were made as per the book.
I would advise anyone else who is gona make their own, to strengthen them before fitting..

Yup James, Cars of the road for winter so mod time.. sump being shortened tonight and repairs to bottom arms..
Looking to fit a screen for next year though

I put an extra 19mm square tube directly under the shock bracket on mine, as I didnt like the look of the original design with no support, I hit some unmarked speed humps at speed and expected to have damaged the wishbones but on checking there was no sign of any damage, maybe you shocks may have bottomed out also ?which would put much more shock loading on the plate.
Paul.

Make or buy new ones the book design deeply flawed.No ammount of fiddling will fix that.

The book shows the suspension bracket plate as being 2mm I was going to make my bones from 25 or 22 mm seamless and up this plate to 3mm possibly with a return of 20mm opposite the balljoint end.

I thought the book used 3mm plate for them, that's what I used anyway and I used a piece of the round tube to join the two sides and reinforce where the plate ends.

Although it will stop the bending using a thicker plate on top of the tubes will produce a WEAKER wishbone due to the notch effect. The plate should be on the neutral axis of the tubes. MK, GTS MNR all have ditched the book design for a much improved versions.

see this thread http://www.locostbuilders.co.uk/viewthread.php?tid=12587

i was going to say from the picture that it looks like 2mm plate, i cant see how ron thought that was good enough.

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Originally posted by JoelP
i was going to say from the picture that it looks like 2mm plate, i cant see how ron thought that was good enough.

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Looking to fit a screen for next year though

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The original lotus RACE car was designed to the absolute minimum weight and strenth. If they could save 1/2 ounce they would. After all the car was repairable after each race. Our cars are street machines and should not compare with out & out race machines.

I add gussetting on all tube contact points, and ad strenght where I think it will help. I do not need a 400 kilo car. I need a street car that will hold up from street conditions. Add a tube under the contact point where the shock tabs are located

(1) The original Lotus was a ROAD car and used suspension parts that have nothing in common with the book design that is very roughly based on the pre-lit Westie.

(2) The Bones being sold by GTS, MNR and MK are much stonger and hence heavier. I have a lower wishbone made with plates supplied by Darren at GTS and the plates are 1/4" (6.25mm) thick --- that is over kill but Darren isn't one to take chances with customers lives.

(3) Adding gussets and fillets isn't a good way to solve what is a structural design problem.

Porbably asked before, but is there any merit in slotting to a suitable length (75+mm?) the each leg of the lower bone (25 x 16 swg) to create a female to accept a 5 mm lower balljoint plate and weld on both sides. The slot could be initiated with a 5 mm hole drilled then slotted and the plate would be radiused for correct profile in the slot.
Is this stronger or weaker than butt welding the plate on the outside of the tubes?

Look at the thickness of the plate. 2MM is too thin. a bar across the two tubes under the shock tabs should make the difference.

quote:

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Originally posted by SilverFox
Porbably asked before, but is there any merit in slotting to a suitable length (75+mm?) the each leg of the lower bone (25 x 16 swg) to create a female to accept a 5 mm lower balljoint plate and weld on both sides. The slot could be initiated with a 5 mm hole drilled then slotted and the plate would be radiused for correct profile in the slot.
Is this stronger or weaker than butt welding the plate on the outside of the tubes?

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Here is a pic of one of my GTS wishbones. (Slightly different to standard ones, but it illustrates how they should be made.....)

Note that the shock mounting plate is on the neutral axis. And measures 1/4" thick. However the wishbones are not overweight! Infact they are quite light really, considering the heavy construction.



David

stuart taylor "book" wishbones use 5mm steel here!!!!

looks well OTT but they don't seem to fail often!