10 replies to this topic

[NDT]

I'm starting to put my 850 back together.

Is there really any merit in a stainless steel nut and bolt kit?

Obviously I'll be using the right grade of HT for anything safety critical.

My instinct would be to either reuse the stuff I took off, or just buy a job lot of the appropriate zinc plate nuts and bolts.

 

thanks in advance!

 

Nick

PS I used search first... 

[Ethel]

I'd go with your instinct.

 

You'd just be moving the corrosion from the fastener to the steel it's holding together in a lot of areas & stainless will be much more of a pain if you have to resort to cutting or drilling it sometime down the line.

 

I'd only consider anything that's nut & bolt  and perhaps thermostat housings: they really do love to corrode into one lump.

[NDT]

Thanks. I’ve just been on namrick.co.uk and seen how cheap their 450-piece UNF bags are! Going HT BZP for most fasteners plus minispares for anything special like subframe tower bolts, tie rod bolts etc

[nollyd]

Make sure you check the tensile strength,maybe too soft,be careful where you use them,

[Spider]

I would warn you against using any stainless anywhere.

 

Stainless has next to no Tensile strength and it will react badly with any steel it's fitted against causing the steel to rust.

[unburntfuelinthemorning]

Thanks. I’ve just been on namrick.co.uk and seen how cheap their 450-piece UNF bags are! Going HT BZP for most fasteners plus minispares for anything special like subframe tower bolts, tie rod bolts etc

I bought the Namrick assorted bag, I've used loads of it, very useful.
 

[Homersimpson]

As above stainless is ok where strength is not required/critical.

I would use stainless screws for the wheel arches for example.

I know there a different grades of stainless but personally I wouldn't risk it with anything safety critical.

[MatthewsDad]

If appearance is important (which after a big job it understandably will be) use zinc plated fixings of the right grade with a squirt of bilt hamber UC once in place to protect them from road dirt. Cheaper too than stainless.

[NDT]

Thanks all.

[bikewiz]

A few things you should know about stainless steel. There are multiple grades and types, the most common is 18/8 known also as 304, the yield and tensile strength is just below grade 5 (bolts with 3 lines on the head) the more expensive alloy 316 generally has a higher tensile strength than grade 5 dependent on size. ARP  https://arp-bolts.com/ make very expensive forged stainless bolts and nuts that exceed grade 8 (six lines on the head). Whenever you use stainless fasteners they need to be coated with a never-seize compound to prevent galling (you guys call it "copper slip" I think, ARP makes some stuff called Ultra Torque I use it it works great)  While it's true dissimilar metals (stainless installed in mild steel) can cause galvanic corrosion, you need another factor to cause real problems, generally salt water. If the car is driven in the winter then you'll have problems if you don't clean it off, that being said you'll have problems with plated nuts and bolts too as the plating can be compromised when tightened up. I've used numerous stainless, rivnuts, nuts, bolts, and screws in my car with no problems,but it really never gets driven in rain and put away before they salt the roads. I like them because it doesn't create another stuck or rusted bolt on my car.

Do some research there is tons of good information on stainless fasteners from the manufacturers in regards to strength and proper use, Fastenal  http://www.fastenal.com over here have pdf files on fastener properties that are helpful.

[greenwheels]

I would only buy bulk nuts & bolts from somewhere like Mini Spares e.g. http://www.minispare... to search      you can then be almost sure you have the correct quality stuff. Nevertheless when working on safety critical stuff, like the suspension, check on Mini Spares website, for example the front tie bar to the outer end of the bottom suspension arm is a special http://www.minispare...e bar bolt.aspx

Using any old bolts is not good enough.