stainless steel rear wishbones

[theelanman]

from
to

the only problem I have is that I'll need to shell out £3000 for the bushes as they are min order of 100 and we need 2 types of bush.....
so 200 @ £15 = £3000
hence the min order of 20 sets.....

Im gutted......

unless I can get say PM or SJ or CN to take a few sets each this could well not happen.....

[theelanman]

revised list

1 ) theelanman
2 ) Mrsdapinky (she can pay for this one )
3 ) rip
4 ) quicksilva
5 ) DeeAitch
6 ) paulwatkins
7 ) Matt RI
8 ) texas2201 - depending on final price
9) A B Munro
10) Andy_J
11) Davidjt
12) Woody - depending on final price
13) Router
14) Rodman
15 ) TrueBlue
16) Geoff
17) stevieshag

and Ill guess we'll lose texas and woody

[dapinky]

G,

Without wishing to try and capsize this at a late stage, (but actually trying to help).

What are the EXACT dimensions of the bush housings on the new parts - i remember you saying something about using a standard size tube for the bushing.

Now that the unit price for the fabrication has increased, I'll get my 'bush' head back on and investigate other options - the £75 a 'bone you quoted seems a bit dearer than I originally found - albeit i accept that they are made to the 'new' spec, not 'off the shelf'.

I can get polyeurothene bars in 38mm diameter for £32 per foot - so it may just be a machining issue which we can overcome.

Just to re-itterate my interest - i don't want to drop out of this one - i want it to succeed for the benefit of everyone in years to come!

As Ian says, if you don't need them now, you will in the future, so someone has to make a stand!

[GeoffSmith]

Gareth,

If they are standard bushes, couldn't you source them from someone further down the supply chain? OK, you might not get them at the same price, but you wouldn't have to buy a shed load of them.

Geoff

[theelanman]

ok bushes......
standard bushes dont fit std tube so we'd need to get the tubes made
standard tubes means we have to get the bushes made.....
its a case of which is most viable.....
tubes made are about £10 a corner (ie £40 a bone) then add £7 +vat for a bush......that makes about £20 per corner or £80 ber bone
doing it the std tube way its say £3 per tube and its £12 +vat per bush...
what I'll do is get a list of std tube from mark and then get a list of std bushes and see which fits......
its sort of 6 of one and half a dozen of the other......
its just less work to get bushes to fit std tube rather than making a load of tube.....and it seemed to save about £2

ok we'll keep going with this and see if we cant get it to £500 a pair
£400 for the metal work and £100 for 8 bushes

[theelanman]

ok here's a leading question
what would people be willing to pay for a pair of stainless wishbones with bushes??

just gives me a target to aim at......

bearing in mind that the metal work is gonna be £400....

Ive then got to get the bushes at reasonable cost.....

if I could get it down to ~£5 a bush and get it in around £450 what would be the response???

just wanna know what Im trying to blag the bush makers to get down to

[davidjt]

I'll still be in at £500, and happy to pay in advance if that helps.

[tweetdriver63]

A pair of galvanized bones from DBE would be $1000 with the bushes, just for comparison purposes.

[dapinky]

Gareth,

Honestly....I'm NOT trying a Greek Hi-jack

However, I've sent some e-mails out today to see about some bushes - I'm trying to get some 16mm and 12mm internal bore SS tube with 3mm walls.

The poly bar isn't an issue, and I'm trying to convince a mate to machine it up on his modelling lathe.

Assuming a 32mm bore stainless 'bush holder' tube, i can't see why we can't get the bushes made up for a reasonable cost - materials should be about £7 each, so with a bit of machining, I'd like to think £10 a corner is achievable

As such, a ball-park figure of £450-£500 is where I'd like to see us aiming.

It's the psycological hurdle of beating the 500 which is driving me on this one!

I'd prefer to have the bone with bushes fitted at source, but would be happy to push for the alternative if it will beat the barrier!!!

(I'll carry on searching )

[fabricator]

another comparison, from a topic about stainless steel rear wishbones & Surrey welding

I leapt on these wishbones about 5 or 6 years ago. They were then, and still are fantastic. The problem was that they were flogging them for about £330 , which, considering the work that had gone into them, made them uneconomical to produce and they stopped. Bummer huh?

=============================================
Garath, the standard tube used for the sample w/bones was 38mm outside diamerer with a 3mm wall thickness ie 32mm inside diameter.
Various wall thickness is available from 1.5mm thro to 4mm in the 38mm o/d tube.Im sure we could find one size to suit the bushes
--------------------------------------------------------------------------
The fabricator

[dapinky]

Fabricator,

(This seems very impersonal - almost like Terminator )

Because the bushes are a 'top-hat' design, the chance of finding a standard one to fit, in the correct shore rating, even with the variety of wall thicknesses availlable, is slim.

As such, the poly bar comes in 38.1mm OD, which could be turned down to 32mm, leaving a Top Hat profile.

It will then be a case of drilling out the centre bore to fit whatever OD tube we can get with a 16mm & 12mm inside diameter.

The bar can be obtained in 70,80,90&95 shore, so going for an 80 shore will probably be the closest to original spec.

Of course, there may be an 80 shore top-hat bush availlable which will do the job, as I was originally trying to find ones to fit the Lotus wishbones, not yours.

The actual bush OD is less of an issue and should be fairly easy to vary, as long as the centres are still in the correct place.

[DeeAitch]

Sorry, but these developments are starting to worry me
I'm already getting cold feet about the price hike - will be very difficult for me to find the dosh at this time of year but I'm right with rip on it. However galvanised ones have lasted a long time on S2's = dilemma
I am getting on a bit, certainly won't need the car another 20 years but suppose I should think of the kids inheritance

What I now need to understand is:

1. If these 'bones will not accept Std Lotus bushes then sorry, I'm out. Lotus designed the car with varying rate bushes to give controlled toe under braking - I want the option to use std bushes if I don't like the feel of the car with the poly ones.
2. What gauge stainless did we decide on?
3. What grade of stainless will be used?
3. What is the all up weight of the stainless v Galvanised ones?
4. What is the status of 'testing' Do we know torsional stiffness for example?

Maybe I'll think of more when I wake up

Hate to be negative on this but at circa £200 I was willing to take whatever came along. Now I'm thinking 'could I do it myself'?

[fabricator]

Posted: Fri 29.06.2007, 12:44 Post subject: stainless steel rear wishbones

--------------------------------------------------------------------------------

stainless steel rear wishbones
who wants some???
Ive got a fabricator to make up a jig and hes gonna start producing....
price will depend on how many people want em and whether you want bushes putting in or not......should be about £250 per side incl vat etc
Im gonna see him this afternoon so should have more info on price etc

I dont think that we will be to far of the original price
unless im missing something, the reduced price appeared on 3/11/07 & corrected a week later
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just a brief word on one part of my business.we fabricate & install food process equipment which is constantly vibrated 24/7, to major companies( kellogs, quaker oaks, mars etc) & in 16 years of business have never had any problems with weld or material failure.
My welder has many qualifications (codings) which enables him to weld aircraft & neucular parts & maybe one day Lotus wishbones.

The fabricator (mark)(terminator)

[GeoffSmith]

Although I came in after the bargain basement price was announced, I haven't pulled out as I still hope Mark and Gareth can come up with top quality replacement at a good price - please don't get too downheartened you two.

I've seen the first set of wishbones first hand and would say they are top quality - the welding appears as good as anything I've seen in aerospace, but please bear in mind I'm not a mechanical engineer so treat me as a semi-illiterate in these aspects.

One thing that has got me thinking is the talk of Shore rating and Dave's comment about the effect on handling. Again, I'm no expert, but drawing on my electronics background and thinking of resistivity & resistance, the Shore rating seems analogous with resistivity (although Shore A rating is dimensionless so next to useless IMHO, but that's mechanical engineers for you ). Now I could make all sorts of value resistors with a material of a fixed resistivity by making them longer or wider. I therefore question whether you can start to deviate too far from the Lotus designed bush physical dimensions using the same Shore rating material - Lotus are pretty good at suspensions and I would have thought they would use stock tube if it was at all possible to keep costs down. If it costs a bit more to bore out stock tube to match the OEM wishbones and turn down the bushes, then that maybe the better way to go; in the overall scheme of things, is it going to make too much difference to the price?

Sorry for throwing something in which raises a doubt and may push up the price, but I think we need to consider as much as possible and make sure we get it right.

Geoff

[rip]

Lotus are pretty good at suspensions

More than pretty good. Damn good. To alter their design would, for me, be undesireable.

[GeoffSmith]

Lotus are pretty good at suspensions

More than pretty good. Damn good. To alter their design would, for me, be undesireable.

Unless it's altered by Lotus? I thought I remembered that the BigSi project had new Lotus suspension components. There's more background here and here.

[dapinky]

Whilst I hear the concerns raised, let me have a 2p worth of opinion here......

Firstly, I fully accept Lotus know more than i do on suspension (and many other things!)

The original rubber bushes should have a shore rating of something like 80 (new), sagging to anything less than 50 as they break up and perish.

Shore 80 is considered to be 'industry standard' for wishbones (in ANY car application).

Superflex already do bushes for other Lotus models (80 shore or 90/95 for track use), but the volume of sales made it worth their while to make them!

How many of us still run on totally original settings anyway?

By the time you factor in the shock absorbers, springs, wheels and even tyres (the original side walls on the original Michelins were unique to the elan when it was developed!), then we are all moving away from the original design somewhat!

Besides which, a rusty wishbone will flex differently than a solid one, and i know which I'd rather trust!

To be honest, for the type of driving that most of us do, it'll make no difference (fast road, occassional track use) and as I say, many have already changed stuff away from the original design anyway!

[Specky]

but please bear in mind I'm not a mechanical engineer so treat me as a semi-illiterate in these aspects.

OK, Just cos I can...




Ironically another Pinky...

Catch you later Geoff...



TTFN

[texas2201]

Sorry Guys I don't need these at the moment and was just going to store them - but it is too rich for me at the moment - just got a big bill for my E30 M3 track car - almost £3K ouch

So I am out - sorry Elanman

Martin

[theelanman]

np probs...

revised list

1 ) theelanman
2 ) Mrsdapinky (she can pay for this one )
3 ) rip
4 ) quicksilva
5 ) DeeAitch
6 ) paulwatkins
7 ) Matt RI
8 )
9) A B Munro
10) Andy_J
11) Davidjt
12) Woody - depending on final price
13) Router
14) Rodman
15 ) TrueBlue
16) Geoff
17) stevieshag