I hope no fellow members were holding their breath for an update on the progress of the National safe. If they did, they are dead by now which might explain why the forum has been a little slow. This has been a drawn out project with waiting for third party suppliers to get their part done. The main holdup was the small sign shop that digitizes the artwork from my tracings. Once my stuff got moved to the abyss of the “someday” counter I knew I was in trouble.
I was getting pissed off in January so I pulled the artwork for the front door cover (the most difficult piece) and searched for someone else to do it. I ran an ad on Craigslist and found an underemployed graphic artist who was eager to make some extra cash. I had the finished artwork back in less than a week. I then dropped off the digital file at another sign shop that had the type of mask I needed to use to be cut. Two weeks later I finally had the finished mask.
Now I was confident the pattern on the original piece could be destroyed so off the cover went to be plated. At the plating shop they told me the spring car parts rush had started early and they were booking three plus months out, oh boy, here we go again. I was pleased to get a package in 6 weeks with parts but when I opened it I found that the cover was in copper instead of nickel. The cover was pitted and it took a lot of buffing to get the metal smooth. Knowing that this was an important piece on the safe and I was very anal about it, Steve wanted approval of the copper base before nickel plating it. It was good and I had it back in four days.
I guess I neglected to take a picture of it in the fresh nickel so we will move on to returning it to the original design. First the heavy vinyl mask is put on. It is cut with extra material to wrap around the edges. The back is sealed off with more vinyl to prevent an unwanted leak. Now comes the hard part. With the artwork and plating costs this is now a $430 part and it now has to go into the blast cabinet to etch the pattern into the nickel. No margin for error now. The unprotected surface is blasted with fresh 120 grit aluminum oxide at a low 60 lbs of air pressure with the gun about 10” away. The blast has to be at 90° to prevent lifting the mask and yet you have to get the surface etched well at the edges of the mask. Here it is after blasting, the mask is white.
Once verifying the blast is even, the residual dust and grit is gently dusted off with a soft brush. Any scratch or defect may show up in the final finish. I robbed one of the wife’s Tupperware storage containers (no I didn't ask) that was the perfect size for dipping the cover in a mixture of selenious acid, nitric acid, and copper sulfate. A tubeless tire plug/patch made the perfect handle for lifting it out of the acid.
Once flooded with the acid it only takes about 45 seconds to darken the nickel. Once removed from the acid the part is rinsed with deionized water, excess water blotted off, and dried with a heat gun to prevent any water spots in the finish.
The original was done by hand so all the variations have been duplicated in the finished design.
The inner door was copper plated and had a similar finish though it was well worn off.
Often called a Japanned finish, the copper is treated with selenious acid. With a simple design to duplicate, I was able to hand cut the mask in vinyl. In tests the highly polished copper darkened well but when this part was dipped it took on an uneven finish. After the panic mode resided I gave the finish a light blast and then it took on an even finish.
The fresh copper finish.
These shiny finishes are difficult to photograph, here you can see the depth and colors better with reflections. Especially in the nickel.
Mask applied, not symmetrical just like the original.
Finished.
I did not have the door back cover plated yet as it fits very tight around the lock and time lock, plating build up on the edges may cause it to not fit. This cover was in pretty good shape so I thought I might be able to salvage it. I polished the bright swirls and then masked them off.
I noticed that when I pulled the tape off from polishing some copper had lifted. When I gave the copper a very gentle blast at 20 psi it removed large areas of the copper from the steel. The copper was just flash plated and had poor adhesion.
Oh well, win some – lose some. Once the door is fully assembled the cover will be fitted, relieved to allow for plating, plated, and then refinished. I doubt I would have been satisfied with the reworked original anyway.
Next up: the final artwork is finally done and and we have a go at the rest of the gold leaf and the pinstriping.
It is time... stand up for a constitutional America. Without it, we have shed blood in vain.