Primarily Petroliana Shop Talk Forums Non-Petro Discussions Non-petro Discussion and Showcase Finish on a 1930's Gumball machine

I have a problem with the finish on the Gumball machine I just started to restore. I'm 41 and it's been in my family since my Grandfather owned his vending machine company in the '60's and early '70's and I've finally decided to clean it up. I took it all apart last night, removed the coins stuck in it, laid it out and figured out what needed to be done. I soaked all of the bare metal pieces in warm water and Oxalic acid to clean the crud off. I've restored a couple Schwinns using this and it worked great on the chrome and bare metal. Today I pulled all the parts, rinsed them and laid them to dry. Then I screwed up. The top inch of the machine has a metal band around it with a few rivets that were rusty so I turned the machine over and stuck it about 8" deep into the acid bath. I thought the machine was porcelain coated and I never imagined the acid would affect the crushed glass. I let it sit for about an hour while I got the kids from school and came home and removed the machine to find the red finish dull, chalky and white. I tried to polish it with fine-cut compound, wash it, scrub it, put wax on it, and finally shoot a little clear over it. Nothing works. I finally wet sanded a small spot on the inside and red was coming off, leading me to believe this is paint, not porcelain.

SO, how do I figure if this is paint or porcelain? If it is paint I'll sand it down and re-shoot it but if it is porcelain, what can I do? I'm crushed.

Acid should NOT attack/dull Porcelain, that why is was used as a finish in Tub, Toilets, Sinks & Signs.
Sounds like a Baked Enamel/Paint.

Was NOT porcelain. Post a picture of the machine. What type of machine is it ?
Dave

Sanding Porcelain is like sanding diamonds you would need 20 grit. Has to be paint.

Here are a few pics. From your info I guess it is paint. So any tips on fixing the paint or does it need to be repainted? And is baked on enamel different than regular enamel? Would heat help the paint "flow"? I'm lost here.

sure looks like porcelain to me...

If it is, is there any hope....

it has the orange-peel look of porcelain...

So how can I find out for sure? And if it is porcelain, can it be fixed?

if its porcelain, theres not much you can do to fix it... if the porcelain finish is gone - its gone for good, especially if you already sanded it and/or sprayed clearcoat on it. Its difficult to say without seeing it in person, but I have had many of signs that have lost their finish and have a milky or hazy finish to them. about all you can do to get that color back or any gloss is keep it coated with something like wd-40, but that doesnt last long.

I just tried to sand a small spot on the inside, right next to the small spot I shot a dab of clear on. The rest is how it turned out after I washed and washed and rinsed. And cussed. A lot. If porcelain is so impervious to acid products, what the heck happened here? Can a person redo porcelain at home or does it need to go somewhere? Where would I send it? Again how can I be 100% sure of what it is?

I have a few master machines like yours pictured and they are porcelain. Sorry to say I do not know of any thing to bring back the color and gloss that was lost to the acid bath.

porcelain cannot be redone at home... restoring porcelain is done by a select few people in the country and I hear it is quite expensive. there are people that opt to sand down the porcelain and spray it with a automobile paint and clear. (but then its not porcelain anymore)

i have no idea what happened with the acids, I'm not a chemist... and I dont play with acids. but as I said, once the finish/shine/gloss/color of porcelain is damaged, it is gone forever.

It appears the firing process of the porcelain failed and the top coat of harden finished has been compromised. I have had this happened to two signs; when spot tested with acid they both lost their luster and the color faded to the dull whitish like yours. Below is a description of the final process when porcelain is made:

APPLICATION & FIRING
The wet enamel mill is sprayed onto a metal substrate such as cast iron grate and fused to the substrate through thermal processes by heating it to 1500 °F. During the fusion process, an inseparable bond forms between the porcelain and the substrate resulting in a completely unique chemical finish that does not peel, flake or rust.

I'm sure you could have the piece redone at an establishment that does the porcelain process; or repaint with enamel paint.

Hello,
I was wrong. What you have is a One cent Master manufactured by Norris Manufacturing Co.They came in a variety of colors: Green/tan,red/black, aluminum/white, etc. This model had a die cast mechanism and they WERE porcelain with the bottom riveted to the body. Most do not disassemble the machine to the point of removing the rivets, but simply clean, buff castings, etc. If you want to try to replicate the porcelain finish the guys on the site could probably recommend some tough automotive enamels.Tape it off and paint it. Many years ago when I had hundreds of machines I used Dupont Imron.
I personally would not remove those rivets. Any more questions?
Dave Jones