Stainless bolt kit - anything to look out for?

[thornley]

I'm kind of with Thornley here (I'm an engineer, although not a chartered one ).

However, for non critical case screws I can't see any problem with stainless. However, I'll still probably replace them with zinc plated due to the potential for galvanic issues.

Just need to find a source of decent quality plated carbon steel screws...

You can use any one of several products on non critical parts and have no problems. The point I try to get across is do not take out high tensile bolts and replace them with generic off the shelf stainless. Looks good but it really defies logic. The work that goes into specifying fasteners for critical use is a science in its own right. If Brembo thought for one minute that generic stainless was a quick pretty fix they would use it, actually cheaper than high tensile, traceable fasteners, batch tested and properly formed. They do not.

 

[LotusMartin]

So, given the list in my original post, which would be considered 'critical parts? I will have a look a the bolt heads and see if I can find markings, but I've not noticed any so far.

I think it's safe to assume anything on the calipers or discs should probably be left alone but what about for example - Front spindle pinch bolt or Torque arm bolt?

 

[MattW]

So, given the list in my original post, which would be considered 'critical parts? I will have a look a the bolt heads and see if I can find markings, but I've not noticed any so far.

I think it's safe to assume anything on the calipers or discs should probably be left alone but what about for example - Front spindle pinch bolt or Torque arm bolt?

I would group spindle bolts, torque arm bolts, suspension bolts etc all within the safety critical camp.

 

[thornley]

I would group spindle bolts, torque arm bolts, suspension bolts etc all within the safety critical camp.

Totally with you. Fasteners are not simply tested for tensile strength but also shear, that horrible force that tries to cut the fastener, impact, elongation, hardness and elevated temperature performance and so many other application required tests. Am becoming a boring bastard now? Bmw has a duty of care and to provide fit for use fasteners. Anyone wants play dough fasteners without any spec get on with it.

 

[Jaws100]

I would group spindle bolts, torque arm bolts, suspension bolts etc all within the safety critical camp.

Totally agree, probably should have outlined that better in my original post, I have only ever replaced non critical bolts with S/S

 

[LotusMartin]

Talk about a can of worms, a stainless can!

I've emailed the supplier, it will be interesting to see what his response is (Chris Shaw)

 

[thornley]

Talk about a can of worms, a stainless can!

I've emailed the supplier, it will be interesting to see what his response is (Chris Shaw)

Yes let us all know if the fasteners match or exceed original spec and get it in writing. Full chemistry and mechanical testing? I have no axe to grind with suppliers, been there done that, but some generic unmarked stainless would not hold two hot dogs together in a bun.

 

[Deleted account 200502001]

How about using ACF50 paste?

 

[autogs]

How about using ACF50 paste?

na that would never strong enough to hold the calipers on