Roll bar and welded nuts on CP3/4

[SeriesLandy]

If the bolts are black 'self colour' 12.9 or 10.9 they WILL rust. You need plated ones so they don't.

[flyerncle]

Its hard to believe that in the land of one of the best steel makers in the world they don't do plated cap screw's but these days anything goes.

I will post you some if you are stuck.


When I made the plates for my roll bar I cut a hole in them to put the tube through and welded it on both sides,wasn't keen on just welding to plate to be extra strong.

[voucht]

Hummm, not sure about the plating thing. At the hardware store store where I buy my bolts and nuts, the 8.8 are plated (silver colour) and d 12.9 are black.

Actually, the idea of using stainless steel bolts was to avoid them to rust, so SeriesLandy is right to point out that the bolts I bought might rust, and I don't want that.

What do you think about this one? 12.9, allen head?


IMG_8120 par Voucht71, sur Flickr


IMG_8119 par Voucht71, sur Flickr

They are actually come covered with oil, they are very fat and oily, so I guess it for protecting them from rusting while stored, and that means that they are not plated and will rust on the car. Am I right?

So, I'll try to find plated 12.9 somewhere else, if you confirm that this one will rust. And if I can't, yes Paul, perhaps I'll accept your offer to post some to me Thank you very much for that, we'll see if it is necessary..., that is very nice. I'll keep you updated.

The car is now stripped off, the chassis is bare again. Water and salt from the road when I drove to the inspection last week made terrible damages (rust everywhere ), and I'm now grinding the welds before I take the chassis to the sandblast and powder coating company, hopefully this week...

[SeriesLandy]

It looks possible that they will rust.

rub the oil off with a cloth (on the head), get it wet and leave it outside for a day or two. That should be long enough to see if it will rust or not.

[jason 82]

I have used those bolts before on my car trailer and they have been fine. They will be good for years & as they are for the roll bar, they won't be directly exposed to the elements anyway. If in a few years they look a bit rough, just replace them, as they don't cost that much anyway.

[jason 82]

Quick thought, why don't you permanently weld the roll bar in ? If it gets rolled, cut the bar off, dress it up & re weld. Even cheaper & even more strength than using bolts.

[TSM Locost]

Stainless bolts can't be used in stress points. 8.8 was min recommended for SVA and i assume for IVA.

A2-70 302 Stainless 7.0
A4-80 316 Stainless 8.0

[voucht]

Thank you for your comments and ideas.

I thought stainless steel was harder than steel, so the grades were higher. wrong idea . But cool, now I know it isn't, and I will not do the same mistake a second time. Thanks!

I tried another hardware store which has more or less everything, and same : their 12.9 grade bolts are black, exactly as the ones I have. So I think I'm going to use these ones for now, and check how they last.

Originally Posted by jason 82

Quick thought, why don't you permanently weld the roll bar in ? If it gets rolled, cut the bar off, dress it up & re weld. Even cheaper & even more strength than using bolts.

Funny you wrote that on my thread the same day I wrote on another thread that I would not weld the roll bar because (as Porkchop says here too) of the fuel tank

Originally Posted by jason 82

they are for the roll bar, they won't be directly exposed to the elements anyway

Are you sure? I think they are pretty exposed to the elements: water/mud/salt from the wheels on the underside, and rain/sun (and snow ) on the top side.

But thanks for the inputs :-)