I'm working my way through the part finish +4" Pinto powered machine that I bought.
The further I get the more I keep re-dooing. Anyway I've been looking a the rear suspension today whilst installing my shocks. For the Shock
Mountings I've used nice new Stainless 8.8 M10's, however it looks like the trailing arms are mounted using M8's.
Are these strong enough or should I change them all the M10's?
Guess I better check the front too.
Andrew
if they are high tensile im sure they would be ok at m8. surely? doesnt the 8.8 stand for something like 8.8 tons in shear?
8.8 if the case would be at a specific cross sectional load - a 6mm 8.8 and a 10mm 8.8 would be different shear loads.....
my shocks have 10mm bolts as std and are 8.8
atb
steve
Nope. Specification of 8.8 (and S in old money) means tensile strength of up to 50-55 tons per sq inch. Doesn't specify shear strength.
Hi'
Since I'm building a stainless chassis I'm
using s/s bolts.
I Hope I can persuade the man at SVA
that 8.8 = A4 80 (see chart)
sorry it's in new money.
Paul G
Rescued attachment bolt ts s.jpg
Hi All,
Thought these were 1/2 inch UNF as standard?? Certainly are for the GTS Nitron units. Moreover, the pre-welded chassis attachment brackets were
drilled to 1/2 inch holes.
Trailing arms & wishbones should be mounted using M12 bolts, for adequate road-going suspension security.
[Edited on 3/4/04 by Dick Axtell]
You use the bolts that fit your suspension bushes. The original Triumph ones were nothing like m12 and they held. If you are using polybushes they might be m12 depending on the crush tubes supplied.
Yes on the front wishbones Triumph used 7/16" unf -- a tiny bit bigger than 11mm
Lotus used 1/2" on the Elan wishbones but they were mounted in single shear
Didn't know you could get 8.8 grade stainless bolts, and I though it was decided in the last disscusion we had that stainless weren't
suitable for suspension jobs?
Or did I dream it?
Cheers
Chris
The teeth on JCB buckets are a type of stainless steel --- stainless steels can be more than strong and tough enough just a question of the type of stainless steel and the cost.
Chris,
Yes I remember something about that too. I did some checking on the site and found
this thread.
By the sound of this thread it is more complex than might be expected and I don't personally think that the benefit is worth the risk of failure.
If you did decide to use stainless then you would be well advised to source them from a highly reputable company and get a certificate which you could
then show the SVA inspector to satisfy him that this was a suitable type of fastener. (Note the points in the above thread about cheap imitation
fasteners with forged grading stamps...)
Cheers,
Craig.
"Yes on the front wishbones Triumph used 7/16" unf -- a tiny bit bigger than 11mm
Lotus used 1/2" on the Elan wishbones but they were mounted in single shear"
They are actually 3/8, a little less than 10mm
JCB bucket teeth are manganese steel, specially chosen as the abrasion it is subjected to causes surface hardening and is not relevant to anything in car construction. They are soft until abrasion takes place and the material is not strong in tension like steel used for bolts.
As far as I can see (which isn't bad with my glasses on) I should imagine that the shear loads on the trailing arm bolts aren't that great anyway, all the latitudinal force is taken by the Panhard rod, leaving the longitudinal forces to be absorbed by four 8mm bolts in double shear. I mean, the popular donor RWD Escort only has one bolt each side of 3/8" diameter holding the axle in place, And I understand that that is holding the spring too, but the forces on that longitudinally will be the same, if not more than in a Locost, due to the extra weight.
quote:
Originally posted by Peteff
JCB bucket teeth are manganese steel, specially chosen as the abrasion it is subjected to causes surface hardening and is not relevant to anything in car construction. They are soft until abrasion takes place and the material is not strong in tension like steel used for bolts.