70 Bright Zinc or Cad Plating

[Bill L.]

I am getting ready to send out my z bar and other parts to be re-plated. The z bar was originally bright silver blue zinc. I know that based on salt tests that cad is far more durable.

Another example is my original connecting link hardware for the front suspension.

Should I have them done in Cad or bright zinc? What kind if any hit would I take for a cad plated part that should be bright zinc?


Thanks!



Bill

[Bill C.]

Re: 70 Bright Zinc or Cad Plating

Best I can tell, it was zinc platted.

[Joe L.]

Re: 70 Bright Zinc or Cad Plating

I am getting ready to send out my z bar and other parts to be re-plated. The z bar was originally bright silver blue zinc. I know that based on salt tests that cad is far more durable.

Another example is my original connecting link hardware for the front suspension.

Should I have them done in Cad or bright zinc? What kind if any hit would I take for a cad plated part that should be bright zinc?


Thanks!





Bill

Bill-----

I don't think that anyone could tell the difference between cadmium and zinc. However, I don't think that most, if not all, of these cross shafts were either zinc or cadmium plated. They look like a GALVANIZED finish (i.e. zinc) to me. I don't think it's a hot dip type galvanizing, though; I think it's what they refer to as electro galvanizing.

[Chuck S.]

Re: 70 Bright Zinc or Cad Plating

I am getting ready to send out my z bar and other parts to be re-plated. The z bar was originally bright silver blue zinc. I know that based on salt tests that cad is far more durable.

Another example is my original connecting link hardware for the front suspension.

Should I have them done in Cad or bright zinc? What kind if any hit would I take for a cad plated part that should be bright zinc?...

A crusty old C1 judge with multi-hundred point judging level and some repute once said here you would need a scanning electron microscope to tell the difference between cadmium and zinc plating. I can't say if Dale knew what he was talking about; but if he was right, I doubt any judge will be able to honestly see the difference with the naked eye.

Another thing I learned when I watched my own hardware being plated is the surface treatment of the part being plated will have a huge influence in how "bright" the plated surface appears. For example, if a part is bead blasted as part of the clean up and prep, there is no way to ever get a bright finish on that part unless the matte finish from bead blasting is burnished off before plating. If you want a "bright" finish, the part will have to start off "brand new mill slick" before plating.

Have you already located a cadmium plater and have a quotation in hand? Cad may be superior to zinc in salt spray tests, but zinc is no slouch either. I doubt any restored Corvette will be operated in conditions that would demand the performance advantage of cad, but for your car, it's your call.

[Bill L.]

Re: 70 Bright Zinc or Cad Plating

Thanks for the detailed replys! I was going to have Richard Fortier do the plating.

I am also going to buy a set of his 70 exhaust tips based on what has been said here on the forum. I have my original tips but Bubba welded the pipes to them. They are repairable but at considerably more cost than his tips.

If the parts are put in a tumbler after having been bead blasted will that clean up the finish so I get the brighter finish? In th ecase of the z bar it is really clean with no rust so I am thinking it will not have to be bead blasted. Same with the hood hinges.

Bill

[Chuck S.]

Re: 70 Bright Zinc or Cad Plating

Thanks for the detailed replys! I was going to have Richard Fortier do the plating.

I am also going to buy a set of his 70 exhaust tips based on what has been said here on the forum. I have my original tips but Bubba welded the pipes to them. They are repairable but at considerably more cost than his tips.

If the parts are put in a tumbler after having been bead blasted will that clean up the finish so I get the brighter finish? In th ecase of the z bar it is really clean with no rust so I am thinking it will not have to be bead blasted. Same with the hood hinges...

If your tumbler and media yields a smooth shiny surface, that will work. What you'll have to watch in that case is that you don't get the parts more "bright" than they were originally. One example is the anti-sway bar links...any new hardware these days (take shock washers as an example) is very bright and doesn't appear original to me. I also preferred to plate my original link hardware. Wire wheeling will also work, but may leave brush marks and sworls on the metal. Once the part is bead blasted, patient hand burnishing with steel wool is required to get you back close to mill finish.

The best prep for plating is acid stripping with muriatic acid (With all attendant warnings and precautions; see the archives). You will probably need to strip the original plating anyway. If the parts have deterioated plating with rust, acid stripping leaves the surface clean, slick, and ready for plating (and also highly susceptible to rust; better move fast). A very light oil film for rust prevention will probably be OK, as most plating processes start out with a boiling hot caustic dip...verify with your plater.

If Fortier is to strip the original plating, then forego any prep except complete removal of oil and grease. If the plater is careless, and any spot of hard grease is left on the part, acid will not remove it. Consequently, you will later have no plating under the dirt.

I'm just curious...have you compared the cost of cad versus zinc? I asked about the source earlier because cad platers, in fact any platers, are becoming an endangered species in the US because of the environmental regs.