aaddpp

You can get many of the same size and grade metric bolts (8.8, and sometimes 12.9) that are sold by Porsche, at places like Lowes / True Value, etc. Porsche bolts however come with a nicer looking gold / bronze electroplating. Does this coating on the Porsche brand bolds (or anything else about them) make them superior (rust proofing, etc???) in any way to the bolts Lowe's sells, or is just a color thing?

auzivision

Electroplated for corrosion protection... and bling... like this:

https://rennlist.com/forums/928-foru...d-goodies.html


Yellow Zinc Dichromate

https://rennlist.com/forums/928-foru...-question.html


https://rennlist.com/forums/928-foru...n-plating.html


https://rennlist.com/forums/928-foru...milar-one.html

My question is... IF one goes through the trouble and expense of plating, what are the pros and cons of Zinc versus Chrome plating? I have an affection for shining object more so than gold.

17prospective buyer

I prefer yellow zinc. It just fits the car. Don't get black oxide btw, i've had bad experiences with anything black oxide, they rust as soon as water touches them...

terry gt

Chrome plating will flake off , and effect the dimensions

GeorgeM

As do I. I have a local guy that does a pretty good job.

dr bob

The "zinc with yellow chromate" finishes fade to gray and darken pretty quickly in the presence of salts or anything low pH. The original class-5 cad iridite finish lasts much longer but is getting really tough to get done correctly. Rob Edwards did a few buckets of bolts in the zinc and chromate, and I used a couple washers on my intake refresh. Then I took them off, because suddenly my original carefully-preserved cad bolts looked dull. Fast forward to a couple years later, and the zinc and chromate bolts and fittings from that batch are already tired and graying, and my originals look better IMHO.

If you can find a good local plater who can re-do the cad, I'd certainly go that way rather than the zinc and chromate method. In my experience, the durability is worth the extra effort and expense.

Dwayne mentioned a plater in nearby-to-me Burbank who was ready to do a batch of his stuff in the correct cad. I never heard back on how that stuff turned out.

17prospective buyer

Are you really sure the original is cadmium?

Hilton

Yes.

Don't wire-brush it, sand blast it etc. without using adequate protection - cadmium is highly toxic and you don't want to breathe *any* of that dust.

My bead cabinet has a good cyclonic dust separator, then passes through a decent filter, then vents the remainder outside (the post-filter outlet has no visible signs of dust deposition after 40+ hours of use).

Cadmium keeps its appearance a lot better than yellow chromate zinc - heat will dull yellow zinc pretty quickly.

aaddpp

The plated stuff looks really sharp, but what if you have an out of sight bolt - in my case one M6 x 12mm that holds the air diverter to the bracket. Ordering that single bolt, with shipping will be ridiculous $$ wise for what you get. Could you just use a metric hardware store bolt in these situations w/o worrying that it fuses to the diverter, or the head rusts off (exaggeration) over time.

Maybach_Man

why not use stainless???

harveyf

There is a lot of science that goes into the proper selection of bolts. And there is a lot of risk in the marketplace that you will get a product that is substandard (commonly referred to as "counterfit").

Use this test: If you look at the use of the bolt and can accept the consequences of the bolt breaking (like the bolts that hold on your license plate), buy the bolt from a big box store. If you don't really like the idea of your brake caliper falling off or your flywheel coming disengaged, or whatever that will put you at physical or financial risk, buy the Porsche bolt and install it to their torque specs. Cheap insurance in my book.

Not all plating is created equal either. The low cost bidder will lay it on thin, with poor long term results.

A middle ground, if you have some engineering training, is to divine from the torque specs (and/or the metric material specs, if you have them) what Porsche intended to use and buy replacement hardware from a reputable source. I do go this route on occasion and buy most of my bolting from McMaster-Carr. If you ask "why not stainless" and don't know the answer, you had better stick with Porsche bolts. (Short answer- stainless as sold in big box stores is generically weaker than a Grade 5 or 8 bolt).

McMaster-Carr's website has some pretty good info listed about both materials and coatings. Their standard shipping reaches me in 2 days, 1 day if I order in the morning.

A good read is Carroll Smiths "Nuts, Bolts, Fasteners, and Plumbing". Also "Engineer to Win".

Sorry to be on my soapbox but use of no name hardware in a high performance car can lead to deadly results. Just channeling Carroll I guess, he says much the same in his books.

The Fixer

I hate stainless because the nuts and bolts gaul.

It depends on the application of course.

And there are different grades of stainless steel,

but i consider stn. stl. fasteners a lower grade fastener for sure.

James Bailey

Harvey hit the nail on the head so to speak Just because it LOOKS like a bolt does not mean it really IS !!!! I really doubt that anyone at Home Depot is doing any quality control checking of the hardware they stock and sell.

Leon Speed

More and more replacement bolts from Porsche are not yellow plated anymore.

aaddpp

Point well taken. I was hoping the answer would be different, but I figured that Porsche bolts would be the way to go.