TheSamba.com :: View topic - Restoring hardware, what is your chosen finish?

Fri Nov 24, 2017 11:25 am

Today, I have a pile of rusty bolts soaking in vinegar. Once these are cleaned, I will need a way to protect them. I don't care for painting bolts. I've never had results that I like. I considered getting an electroplating kit. What method do you prefer? Is there something that gives good results that I should try?

Fri Nov 24, 2017 11:27 am

How much do you want to spend?

Some kits are probably better than others. You can make your own kit from Amazon/Lowes/Home Depot/etc.

Fri Nov 24, 2017 11:29 am

The kits I saw were 200ish. I'm not opposed to spending that if it does all the hardware. I've never used one before, so I don't know what to expect. This isn't going to be a show quality restoration.

Fri Nov 24, 2017 11:57 am

You can buy the pieces for less than 200. The only piece that may be a bit pricy is the power source.

I would say you can make your own kit for $50 easily. You'll want to clean the bolts immediately before putting them in the solution with muriatic acid. You can buy a gallon from Lowe's.

Fri Nov 24, 2017 12:04 pm

Home made kit probably gives similar results to factory kits.
https://www.google.com/search?q=home+made+electrop...fox-b-1-ab

Fri Nov 24, 2017 12:06 pm

I made my own. It works very well.

Sun Nov 26, 2017 7:45 pm

What the hardware is...and what it does....is what decides what coating it needs. If it needs to be zinc....you can electroplate at home with zinc for fairly cheap.

For most under the hood bolts and nuts....black phosphate with an oil pickle is just fine.

For items not likely to be chewed up....plates and connectors...distributor parts and door internal lataches... and need a harder surface and high rust proof.....use electroless nickle.

Electroless plating is superior in finish and accuracy to electro plating. There are some electroless zinc methods....but they are chemically complex. You can also do chemical galvanizing to get zinc without plating. Depends on what you need. Ray

Mon Nov 27, 2017 9:32 am

raygreenwood wrote: black phosphate with an oil pickle is just fine.

I'm ignorant. I Googled "oil pickle", but that was no help.

Explain please?

Mon Nov 27, 2017 10:07 am

You can put together a home zinc playing kit from almost scratch for about $25. I’ll hunt down my old thread with a good link.

Mon Nov 27, 2017 10:43 am

vwtrey wrote: Today, I have a pile of rusty bolts soaking in vinegar. Once these are cleaned, I will need a way to protect them. I don't care for painting bolts. I've never had results that I like. I considered getting an electroplating kit. What method do you prefer? Is there something that gives good results that I should try?

Get a bolt tumbler and media and let them rip for a few days. If you want to plate them they need to be spotless clean and no microscopic rust.

Yellow zinc was original for most all fasteners and hardware if you care about that. People don't realize that today because the yellow didn't last.

Mon Nov 27, 2017 11:50 am

for what the local industrial plater charges me to do huge batches, it is not even remotely worth my time or effort to do plating at home.

i almost always get the hardware that i use coated in black or clear (silver colored) zinc. have yet to run into any rust issues. in fact, i've had a piece sitting outside for about 4 years, as a test against the weather, and have yet to see a change. the clear (silver colored) zinc can be a bit brighter than i prefer for distributors, but i have yet to hear any complaints from customers about it.

phosphate leaves too rough a coating for my liking, and the plater did not recommend it for long term rust prevention. not sure what oil pickling is.

Tram, not sure when yellow zinc came into fashion, my guess is early 1970's as I have many early 60's NOS hardware, and it is definitely not yellow. i do have some NOS early 70's hardware and a lot of it is yellow. i also think it is cad plated, not zinc.

Mon Nov 27, 2017 12:35 pm

hazetguy wrote: for what the local industrial plater charges me to do huge batches, it is not even remotely worth my time or effort to do plating at home.

i almost always get the hardware that i use coated in black or clear (silver colored) zinc. have yet to run into any rust issues. in fact, i've had a piece sitting outside for about 4 years, as a test against the weather, and have yet to see a change. the clear (silver colored) zinc can be a bit brighter than i prefer for distributors, but i have yet to hear any complaints from customers about it.

phosphate leaves too rough a coating for my liking, and the plater did not recommend it for long term rust prevention. not sure what oil pickling is.

Tram, not sure when yellow zinc came into fashion, my guess is early 1970's as I have many early 60's NOS hardware, and it is definitely not yellow. i do have some NOS early 70's hardware and a lot of it is yellow. i also think it is cad plated, not zinc.

Yes, cad originally, but yellow zinc and Caswell's "Copy Cad" is indestinguishable from the original. I've had lots of early Type 3 hardware come through my hands and it's been yellow. since Type 3 began in 1961, I'd say it began in the early '60s at least. That's about the time it started appearing on Mercedes and Porsche hardware as well.

Tue Nov 28, 2017 6:03 pm

Caswell's "copy Cad"…. Bought their plating kit almost 20 years ago. Still going strong after all these years...

Wed Nov 29, 2017 12:19 pm

hazetguy wrote: for what the local industrial plater charges me to do huge batches, it is not even remotely worth my time or effort to do plating at home.

i almost always get the hardware that i use coated in black or clear (silver colored) zinc. have yet to run into any rust issues. in fact, i've had a piece sitting outside for about 4 years, as a test against the weather, and have yet to see a change. the clear (silver colored) zinc can be a bit brighter than i prefer for distributors, but i have yet to hear any complaints from customers about it.

phosphate leaves too rough a coating for my liking, and the plater did not recommend it for long term rust prevention. not sure what oil pickling is.

Tram, not sure when yellow zinc came into fashion, my guess is early 1970's as I have many early 60's NOS hardware, and it is definitely not yellow. i do have some NOS early 70's hardware and a lot of it is yellow. i also think it is cad plated, not zinc.

Oil pickling....is taking phosphated (and other types of conversion coatings)....which as you mention do not have long term rust resistance....and place them in a vat of oil or penetrating oil fluid...and bringing them up to a fairly high temperature. This opens the pores between the coating and metal and puts lubricant in them.

This makes them much more rust proof in semi-sheltered usage...like say under the dash or in the engine compartment.

Also..there are a great many sealer coatings (spray or dip) that black phosphate hardware can now use that make them virtually rustproof in semi-sheltered use....for many years.

Yellow zinc chromate came into fashion in the 1920's....pioneered by Ford.

There are a huge range of chromate colors...not just yellow. They range from bright blue, through pinkish, greenish, yellowish...and many non-chromate based coatings for zinc. None of the non-chromate based top coatings are yet as good as the original chrome based ones but they are getting there.

The chromate coatings are not there to be pretty...but because they can be at the same time...you get the range of colors available.

The use of a chromate top coat for zinc plating easily doubles its anti-corrosion lifespan.

The gist is this: Zinc....is just about THE BEST...SACRIFICIAL anti-rust coating for ferrous metal on the planet. The only thing that can actually beat it....is zinc-nickel plating.

The problem with zinc....is that in order for it to work as an anti-corrosion coating....the zinc itself MUST corrode. Even if the zinc plating is spotty...it still works because its an anode.

As zinc corrodes it produces what is termed in the plating industry as "white rust"...that powdery residue we see on non-chromated zinc plated parts ...for example...like the vacuum advance units on our distributors. With age they get that greyish white powdery residue. That is the zinc plating doing its job.

But...once this white rust/corrosion starts....it will never stop over numerous years until the zinc is depleted and then actual ferrous metal rust can start.

The chromate...originally containing hexavalent chrome...very toxic...was simply a dip sealant with the right anode/cathode mix to bond to the zinc. It prevented oxygen from getting to the zinc and starting the white rust process. The chromating process only takes seconds or minutes and is done after the zinc plating.....after the zinc parts have been rinsed and cleaned again....and then they have their surface tension changed again usually by a dip in something like tri-sodium phosphate..then a dip in the heated chromate solution...done. Sometimes they get baked afterwards to dry them completely.

Another type of "pickling" that is done on virtually all plated metals....is acid pickling....that is also sometimes called surface activation.

The object is to have a short dip in a SPECIFIC acid to get the surface reacting and ready to bond to whatever metal ion you are plating on it.

Its usually not a super concentrated acid...but that depends on the acid type.
There are acids that are oxidizing and acids that are non-oxidizing. It depends on the metal type. Sometimes the metal needs a lengthy time in an acid mix.....sometimes just a short dip.

If you go too long on some metals...it creates hydrogen embrittlement on the surface. This can cause porous plating that can allow oxygen through to rust.
Another example is too long of an acid pickle on cast iron exposes carbon and molybdenum in the surface pores which interfere in plating and cause porosity. Ray

Wed Aug 07, 2019 2:52 pm

Has anyone used the Caswell black oxide kit? It has some pretty mixed reviews. I'm also trying to figure out if the cold black oxide process even comes close to the factory hot black oxide process in corrosion resistance. Any assistance/thoughts would be greatly appreciated!

Thu Aug 08, 2019 11:07 am

raygreenwood wrote: hazetguy wrote: for what the local industrial plater charges me to do huge batches, it is not even remotely worth my time or effort to do plating at home.

i almost always get the hardware that i use coated in black or clear (silver colored) zinc. have yet to run into any rust issues. in fact, i've had a piece sitting outside for about 4 years, as a test against the weather, and have yet to see a change. the clear (silver colored) zinc can be a bit brighter than i prefer for distributors, but i have yet to hear any complaints from customers about it.

phosphate leaves too rough a coating for my liking, and the plater did not recommend it for long term rust prevention. not sure what oil pickling is.

Tram, not sure when yellow zinc came into fashion, my guess is early 1970's as I have many early 60's NOS hardware, and it is definitely not yellow. i do have some NOS early 70's hardware and a lot of it is yellow. i also think it is cad plated, not zinc.

Oil pickling....is taking phosphated (and other types of conversion coatings)....which as you mention do not have long term rust resistance....and place them in a vat of oil or penetrating oil fluid...and bringing them up to a fairly high temperature. This opens the pores between the coating and metal and puts lubricant in them.

This makes them much more rust proof in semi-sheltered usage...like say under the dash or in the engine compartment.

Also..there are a great many sealer coatings (spray or dip) that black phosphate hardware can now use that make them virtually rustproof in semi-sheltered use....for many years.

Yellow zinc chromate came into fashion in the 1920's....pioneered by Ford.

There are a huge range of chromate colors...not just yellow. They range from bright blue, through pinkish, greenish, yellowish...and many non-chromate based coatings for zinc. None of the non-chromate based top coatings are yet as good as the original chrome based ones but they are getting there.

The chromate coatings are not there to be pretty...but because they can be at the same time...you get the range of colors available.

The use of a chromate top coat for zinc plating easily doubles its anti-corrosion lifespan.

The gist is this: Zinc....is just about THE BEST...SACRIFICIAL anti-rust coating for ferrous metal on the planet. The only thing that can actually beat it....is zinc-nickel plating.

The problem with zinc....is that in order for it to work as an anti-corrosion coating....the zinc itself MUST corrode. Even if the zinc plating is spotty...it still works because its an anode.

As zinc corrodes it produces what is termed in the plating industry as "white rust"...that powdery residue we see on non-chromated zinc plated parts ...for example...like the vacuum advance units on our distributors. With age they get that greyish white powdery residue. That is the zinc plating doing its job.

But...once this white rust/corrosion starts....it will never stop over numerous years until the zinc is depleted and then actual ferrous metal rust can start.

The chromate...originally containing hexavalent chrome...very toxic...was simply a dip sealant with the right anode/cathode mix to bond to the zinc. It prevented oxygen from getting to the zinc and starting the white rust process. The chromating process only takes seconds or minutes and is done after the zinc plating.....after the zinc parts have been rinsed and cleaned again....and then they have their surface tension changed again usually by a dip in something like tri-sodium phosphate..then a dip in the heated chromate solution...done. Sometimes they get baked afterwards to dry them completely.

Another type of "pickling" that is done on virtually all plated metals....is acid pickling....that is also sometimes called surface activation.

The object is to have a short dip in a SPECIFIC acid to get the surface reacting and ready to bond to whatever metal ion you are plating on it.

Its usually not a super concentrated acid...but that depends on the acid type.
There are acids that are oxidizing and acids that are non-oxidizing. It depends on the metal type. Sometimes the metal needs a lengthy time in an acid mix.....sometimes just a short dip.

If you go too long on some metals...it creates hydrogen embrittlement on the surface. This can cause porous plating that can allow oxygen through to rust.
Another example is too long of an acid pickle on cast iron exposes carbon and molybdenum in the surface pores which interfere in plating and cause porosity. Ray

Nice. Thanks!

Thu Aug 08, 2019 11:28 am

Another option for a black coating is Birchwood Casey Super Blue. It's a combination of selenious acid, nitric acid and phosphoric acid and is intended for ferrous metals; it won't work on stainless steel or aluminum. Look it up on the googles.

Thu Aug 08, 2019 8:18 pm

Elroyyy wrote: Another option for a black coating is Birchwood Casey Super Blue. It's a combination of selenious acid, nitric acid and phosphoric acid and is intended for ferrous metals; it won't work on stainless steel or aluminum. Look it up on the googles.

That looks like the way to go, then a hot oil pickling to seal it. Thanks for the input.