Black oxide fasteners not all "equal"

[Jack Gifford]

The finish on these bolts was a nice match to the satin black paint under the hood of my '59 GMC so I hadn't painted them. They looked fine for a couple of years, but as I recently got the truck out of winter storage- UGH! I don't remember the source of them, but I've usually had better experience with black oxide finish.

[Stainless1]

Hey Jack that looks like a lot of the fasteners on the race car.... mine, not yours....  :lol:

[manta22]

Jack, the black oxide doesn't provide much protection. It's the oil that the surface retains that does it, just like gun bluing.

[jww36]

McMaster-Carr offers 18-8 Stainless Steel fasteners in black oxide. A nice satin finish. Price is not bad. A package of twenty five 1/4-20 allen bolts is about 8 bucks.

[salt27]

Gus used black oxide allen buttonheads to attach his pickups wheel flairs (it was my idea).

A couple years later he needed to remove them to paint the truck and we had to use a sawzall but they did look nice.     :-P

  Don

[fordboy628]

Jack, the black oxide doesn't provide much protection. It's the oil that the surface retains that does it, just like gun bluing.

Of all the "processing", black oxide provides the least corrosion protection.   As Neil points out, it's the oil on the black oxide that "delays" corrosion.   The "black" is for appearance.

"Plating", of various types offers somewhat better corrosion resistance, but even chrome plating can be corroded underneath.   You might want to consult a chart of "salt exposure corrosion results for various materials, platings and coatings."

I suggest that racers choose a fastener based on suitability/cost/looks/corrosion resistance, not in any particular order.   If my memory serves me correctly, 316 stainless has the best corrosion resistance of any readily available fastener.   It is, of course, very expensive.

To quote the "Wisdom of Booger",  (an old racing "acquaintance" . . . . . .)
"Yo pays yo money, and takes yo choice."


F/b

[ggl205]

FB is correct. Black oxide is for oil retention and little else. Widely used on camshafts, lifters and other engine components needing oil retention.

I purchased stainless steel, 1/4-28, flat head hex drive bolts from eBay for around $12 per pack of 25. Not sure what grade stainless they are but have worked out well so far. You get your choice of length too.

John

[Stainless1]

Hey John, faster than ebay.... Wichita Fasteners on Oak Street in Delano... and cheaper! 
Stainless would look good on the truck Jack, just remember all stainless fasteners need anti-seize.
I have a lot of 1/4 and 5/16 fasteners on the race car... including stainless nyloc nuts... yep those get anti-seize as well.
I think the same as Gun Blue... a little wax protection can help... 

[wobblywalrus]

Instead of anti-sieze I am using Loctite 567 thread sealant with a 25 percent reduction from the dry torque reading to account for the lubricity.  Enough sealant is used for it to ooze out from under the bolt head, nut head, or washers when the fastener is tightened.  The goop provides some locking capabilities and it seals the gaps between the fastener and the clamped pieces to prevent electrolytic corrosion.  It seems to work OK.  No problems experienced except for the cost of the stuff.

[Jack Gifford]

... Stainless would look good on the truck Jack...

"Looks good" is in the eye of the beholder. My goal with this truck, generally, is to preserve the original '59 design. Bright bolt heads on the black inner fender panels would look garrish. So I just cleaned up the rust and painted them black.
Thanks for the comments. I did use plenty of stainless fasteners to put the truck together, mostly where they're out of sight.

[Stainless1]

Jack... lots of stainless fasteners come in black....

[Jack Gifford]

I didn't know that. Thanks, Robert.

[kiwi belly tank]

Silicone spray is not only good for sealing moisture out of electrical connections but will prevent corrosion forming on bare metal parts like bolts & nuts. I've even had safe sex with it! aktion086 Ok, that was a lie but it got your attention didn't it!
  Sid.   

[salt27]

Silicone spray I've even had safe sex with it!
  Sid.   

Sid, none of my business but I'm curious, was someone/something else involved or just you and the silicone?       

[JimL]

I should comment on silicone spray and.....anything to do with a vehicle.  That silicone was a nightmare for us in the auto industry.  Much of the "shine up the interior" stuff has silicone in it.  We saw many failures with Cruise Control and brake electric circuits because it found its way into switches.  Silicone spray used under the hood to "spiff up" a used car gave us EFI problems, ABS failures (repeat trouble codes until you just threw away everything and started over). 

Unbelievable how many crazy problems were caused by "auto detailer" services.  Especially the ones that come to your home or office and "detail" your car.  We spent years teaching the dealers how to avoid ruining a perfectly good car/truck....and then the customer clips a coupon out of the paper and orders up a boat-load of trouble.

The worst place to have silicone spray is around anything painted.  It is an amazing molecule that figures out how to creep under paint and start peeling it off.  All it takes in one little pit or scratch and away it goes.

We went to BIG extremes of control in our factories to prevent bad paint jobs.  Employees are not even allowed to use deodorant or hair products, because there is a little silicone there and it can get into the air and make fish-eyes in the paint.  We even had to carefully cover our shoes before entering the finish booths, because many shoes have traces of silicone that was used in the molding or assembly/stitching processes.

We finally forbid our dealers to have any silicone sprays in the parts or service departments.  What a nightmare....the stuff was like a virus.....it could get places we couldn't imagine and was nearly impossible to clean up.

I still hate that stuff. :x :x