What is this bolt coated with?

Does anyone know for sure.

It's the ones for the suspension with the horse on the head.

The more I look at them they look like they were painted.

Anyone know painted at plated? Maybe plated then painted?
I was going for clear zing at first but now I'm not sure.

Thoughts

Thanks
Jp
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Side view
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That is how they look brand "new" from Ferrari. It is like a zinc coating that was improperly prepped or something, but I don't really know. All the ones I've seen look just like that.

 

Yeah but do they have corrosion on the heads? That's what I'm fighting so I plated one of them tell me what you think.

It's a little shinny
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Bolt head
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Be careful about playing high strength bolts. Generally the need to be baked for a period of time or you can get hydrogen embrittlement.

 

Well I need to do more research. Maybe I will have to bake my hardened parts..

 

Steel with an ultimate tensile strength of less than 1000 MPa (~145,000 psi) or hardness of less than 30 HRC are not generally considered susceptible to hydrogen embrittlement.


So my question (if anyone knows) what grade are these Suspension bolts they have no markings on them.

Have to make some calls

 

Johnny, did you test the hardness on a Rockwell tester?

 

Nope that's why I'm asking since they don't have markings on the head.

But might need to get one.

 

If you don't have access to a Rockwell tester, send one to me and I'll get it done.

 

I'm kinda bumbed now, not sure if I can make all this look pretty again.
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Well, alternatively, if pretty is the goal.
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Haha I thought that was just for vaginas.

 

Doesn't look like corrosion to me, just "wear and tear" and the original finish has abraded off.

 

Agreed. All my suspension bolts look like yours. Still wondering about the make and coating because I'm sure these are expensive to replace with the horsie stamp.

 

Johnny, it's possible the coating is just tarnished or dirty. You can try and glass bead blast one and see how they look. We have a blaster at my shop if you want me to try one.

 

The pics are not showing it well but there is some rust surface corrosion on these parts.

Most of the yellow chromate parts have a scale on them like it should but a lot of the suspension bolts the bolt heads and the threads that were exposed have rust.

 

Oh no I have my own blasting cabinet, when blasted with glass beeds they are brought back to the nice shiney bare metal.

The one horse bolt I plated the other day had some rust pits on the shank of the bolt and surface rust on the bolt head, but the glass bead cleaned them up just fine.

I guess I could just live with them, Since the photos Daniel showed they really are not all that

Ill show a photo of the blasted one so you can see the finish.

 

First pic is just a few of the bolts some rusty some just dirty but all have some corrosion on them.

Second pic is a pretty rusty bolt head the on on the right has been glass bead blasted.
I also have a parts tumbler and they clean up well in that as well.

I have a local plater that can plate in zinc but I'm not sure yet what these were done in maybe zinc chromate?

The yellow gold parts I'm sure are yellow chromate. But plating them is $75 a pound so the suspension brackets are over 5 lbs so almost $400 just to plate them..

Ok seems to be an issue with my stupid I phone and uploading pics so the first one shows the rust.
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Other pic showing some of the corrosion on different hardware.
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Appears to be "dull Cad" to me. Many production shops produce a Cad coating that is shiny, perhaps that is what you have already experienced. Some specialty shops can produce the dull finish. I used Industrial Plating Company, Inc. for numerous finishes on a Concours resto for my "muscle car".

You can email Henry a photo for his opinion (see contact link)- I suspect any Ferrari restoration expert can readily answer your question.

Lane

 

Johnny, you could do electroless nickel and bead blast and it would look close and never rust again. Or, thin dense chrome would look very good but not as corrosion resistant

 

Yes there are a bunch of different coatings you will find on must and bolts even this ferrari I have seen at least 5 different coatings used on the bolts nuts and washers.

I'd really rather not ship parts out I'm already worried about some getting lost if I take this stuff out to a plater.

 

Almost $27 ea.
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