Ok, So this question has been in the back of my brain for a little while as I'm getting ready to clean up the cowl vent deflector mechanisim along with the wing vent frames for the 52 and the 53 and the hood latch plate, etc etc. they all appear to have been galvanized originally.

I'm wondering if after I sand them to clean off the surface rust if they should be painted black or whatever color of choice or if I should spray them with a rattle can of that "Cold Galvanizing compound paint" ?? I think thats what they call it from the big box stores?

Maybe it really does not matter either way but wondered if anyone here has an opinion on the matter.
If I was to just spray them I would probably use a silver or light grey paint just to somewhat match what it would have looked like originally.

seems like I recall a discussion on this once a few years ago but obviously did not do a search. guess maybe now that I've typed this up maybe I should...

 

I remember from back in my days of fabbing up parts for water towers that some paint won't work with galvanizing.....but thats as far as my memory goes.

When I fabbed up my tailgate I used some rigid conduit (EMT) for the upper and lower tailgate rolls. Rigid conduit is galvanized so I hope I didn't screw myself. the conduit was the right size and its what I had available at the time so I hope it all works out in the end...lol

Bobby

 

What about sandblasting? Maybe it'll etch them enough for the primer and paint to adhere.

 

I think you can also "etch" the surface with acid...muruatic? maybe?
Dang, its been a lot of years since I was in that industry and I didn't pay much attention to the painting part.

Bobby

 

I have been using SEM Metallock DTM epoxy primer on just about everything for the last few years. I really like the adhesion and the way it sands. I have topcoated with everything from House of Kolor to PPG to Omni and other cheaper paints. I see no reason why galvanized would be a problem, just scuff it and wipe it and shoot it.

 

If the galvanize coating is in good condition and you don't need to change the color,just clean it up with a wire brush or scuff pad and leave it as is.

 

Wipe it down with white vinegar and you should be able to paint whatever you want on it.

 

I think those parts were plated, not galvanized. If my equipment was set up, I would offer to re-plate those small parts for you.

A generator cut-out cover for a 37 Ford I did. Does the finish look something like this, sans the rust?



and this?

 

Quite some time ago someone either here on FTE or the old Bonus Built site shared his technique for zinc plating parts. I thought I had it copied somewhere on my computer but I can't find it. I did find a site that had what looked like the same type of procedure:

Zinc Plating at Home - Triumph Forum: Triumph Rat Motorcycle Forums

 

Thanks guys for all the answers, I supposed they could have been just plated? not real familiar with galv vs plate but just want to clean them up and paint or just finish so they look like original would have looked.

1952 Henry Yes those parts look great, and I imagine thats what these parts would have looked like 59 and 60 years ago.
thanks

Some of the parts are not rusty at all like the ash tray holder brackets but the wing vent frames have quite a bit of surface rust along the bottom edges. those parts will never be seen once installed so is not really an issue but just didn't want rust to resurface sooner than neccesary. that and I was mostly just curious I guess.

The Hood latch mechanisam will need to be more durable since it will be seen and be subjected to contact with the latch.

 

are you sure it's galvanized, especially if it's rusted?

 

I actually tried that, and the results were so-so. It worked, but required a bit of polishing to get them to look right. The biggest issue is getting the right amount of current. Too little, and your plating just doesn't happen. Too much, and the plating gets rough, lumpy, etc. It is inexpensive to do, and if with some experimenting, you could have decent results.

I have used a battery charger with a rheostat switch that once served as a car heater control. It worked in a pinch, but would start smoking after a short amount of time. I have an adjustable power supply that adjusts from 0-10(?) amps and 0-30 volts. It's nice because different sized parts require different amount of amperage. However, that set me back $300. Add to that the plating chemicals and nitric acid (used to brighten the part after plating, not easy to get, either) and it is a small investment. I advertised in different forums for plating small parts and got back quite a bit of my outlay.

The biggest part in plating is the prep work before hand. Much like most other endeavors.

As to the difference between plating and galvanizing; plating uses electricity and a salt of the plating metal to transfer said metal from one surface to another, whereas galvanizing is actually dipping the part into a hot bath that coats the surface. I'm not schooled in depth on galvanizing.

Next time you are in a decent hardware store, check in the fastener aisle. Lag bolts are offered in both plated and galvanized finishes. You can see the difference.

I replate all the linkages and other steel parts in the carburetors I restore. I know of other carburetor restorers that simply bead blast the rust off then clear coat the bare metal. Some parts are dipped in yellow chromate if that's what was done originally. That helps save the zinc surface from corrosion.


Base from a original Holley that sits atop a 428 CJ equipped 1969 Shelby GT500. Didn't take a picture of the rest of the body when I finished restoring it. D'oh!


Sorry for the rambling.

 

Galvanized parts will rust. Whether through plating or galvanizing, the zinc, or cadmium will succumb to oxidation the same way the base metal would. The corrugated tin for barn roofs and grain bins, for example, shows rust after many years in the elements. Gleaner combines, and many separators from years ago were made from galvanized steel. They show rust from years in the rain, snow, etc. This has come up in old machinery forums when someone is wondering how to restore the metal finish on such equipment.

 

I used galvanized EMT like Bobby; I have used Muriatic acid in the past to etch before painting.
Vinegar sounds a lot greener for the environment.

There is a galvanizing zinc based paint that may work. I used that on some of the under dash items as well.

Tom

 

hot dipping and electroplating are both considered galvanizing if the coating is zinc over steel. Electroplated zinc can look smooth and shiny like EMT tubing or fence posts, or crystaline like heating ducts. Hot dipped is dunking the part in molten zinc and is dull grey, thick and rough looking like some fasteners. The zincis much more chemically active than steel so it protects by being a sacrificial coating that reacts with the environment before the steel. The steel won't rust until the zinc has reacted away or the coating has been damaged exposing the steel. If the surface is rusted either the zinc is all gone or was never galvanized in the first place.
Zinc rich coatings such as weld thru primer may help reduce corrosion over plain primer, but is not as effective as plating or hot dipping where the coating is in full physical contact with the steel substrate.
As far as overcoating galvanized metal: fresh electroplated galvanize metal should be washed with a strong solvent then scuffed with a scuff pad or fine sandpaper or acid etched with vinegar or a 5% muriatic acid wash (be sure to neutralize the acid wash with baking soda solution and plenty of water rinsing) before priming with any good primer. galvanized metal that has been exposed to the atmosphere long enough to dull or become chalky just needs to be cleaned before painting.