#camera repaint

[evanmayer]

kiev 4a tune-up, pt. 4 (reassembly)

This is the conclusion of the kiev 4a tune-up. Reassembly is after the break.

The body of the camera was pretty lonely at this point, having been in a box for about a week while I was painting. While everything was exposed, I took the lighter fluid and q-tips and cleaned out any congealed, wax-like grease I could find, as I had been doing during disassembly.

Here’s the top of the camera again, this time with a more substantial light baffle in place.

It’s very opaque black plastic, cut to the shape of the top area of the camera. My plastic is known to be 100% light-tight; I cut a small portion off the top of a bag of Ilford photopaper (in a very dark room, since the bag had to be partially open for the cut and I didn’t want to expose the paper). You could use thick garbage bag or black construction paper. I removed the silver plates on the right and left, which usually hold the rangefinder glass in place, put the plastic under them, and screwed them back on, holding the plastic in place.

From this point on, I followed the Kiev Survival Site’s disassembly instructions in reverse, referring to my own quick sketches of which parts went together in which order, and which screws went in which holes. Since it had been a week since disassembly, these sketches, my photos, and the guide were essential.

Here are some photos of the light seal replacement I did.

The Kiev Survival Site suggests a type of foam to use, which I cut into one long strip. I wedged it where the “yak hair” black yarn used to be, in a slot just inside the top edge of the camera back. I used a pair of tweezers and a screwdriver, gently. It’s slightly more grey than black in these images.

Then I had to reglue the leatherette to the black panel. I used Pliobond 25, a stanky contact adhesive that dries flexible and allows removal at a later date. Perfect for leatherette repair. The directions are simple and printed on the container.

Here it is after complete reassembly. I would suggest waiting a full week for the paint to harden before attaching trim, mine was still dangerously soft as I jammed pieces on and screwed them down.

The keen-eyed observer will notice that the engravings are painted over. I haven’t quite decided if I want to fill them in, but the usual practice is to use a Lacquer-Stik, or some other kind of model paint and a fine brush, as detailed in the link in the second post. Apply liberally, wipe off the surface, and the paint remains inside the engravings. My white Lacquer-Stik is in the mail.

And it’s done! The first roll will determine if I’ve done a good job or not. Please feel free to leave me a message if you’d like anything clarified. I don’t claim to be an expert, but this is how I did it, and I was satisfied with the results. 

Please share if you found this interesting or helpful.

[evanmayer]

kiev 4a tune-up, pt. 3 (painting)

Painting is after the break. This is a long one.

Any painter will tell you the best finishes come from good prep work. This is no exception. After roughing up the remaining exposed metal with the brass wire brush and cleaning it, I was ready for paint. A side note: from now until the paint is dry, it’s a good idea to maintain a well-ventilated, temperature-controlled, dust-free environment. This isn’t always practical for the DIY-er, so I’ll go over the implications as they become relevant. I handled the parts and did the painting with nitrile gloves to keep oil off, and wore some goggles. These are the paints I chose. 

The links in the second post pointed toward using a self-etching primer on bare metal. I wanted a black semigloss finish, so I chose this enamel. Enamels take a long time to fully cure and harden, but should be more durable in the long run than other varieties if applied correctly. This was my first coat of primer. I used long, steady passes, starting the spray before the part, and ending the spray a few inches after reaching the end of the part.

You're looking for 100% even coverage. It took me another coat after this one to get there. I followed the drying instructions on the can. The finish seemed a bit sandy and uneven, but I attributed it to the nature of the primer. Here's how it looked after 3 coats of enamel:

Way, way too matte, and very rough. The finish absorbed a lot of light and was difficult to photograph. This was a result of the lack of a temperature-controlled environment. At 108F (ambient midday temp in Tucson), the solvent carrying spraypaint evaporates soon after leaving the spray nozzle. This results in a "dry spray," essentially, tacky spraypaint dust sticking to the surface in a rough layer.

The solution was to wetsand the rough layers down (almost to the primer) until a smooth surface was achieved. I learned to wetsand from this guide (ctrl+F search "wetsand" to skip to the good stuff). The basic concept is to use waterproof sandpaper, soaked in water or water and soap as lubricant, in increasingly finer grits, to get a smoother finish. I knocked off the top layer with 600-grit, then switched to 1000-grit. I held it up against backlighting to check the finish. Dull spots had been sanded, shiny spots hadn't been hit with sandpaper and are deduced to be lower (see this Instructables article, step 3). I didn't wear nitrile gloves during sanding. I rinsed the parts in water and patted dry with a lint-free cloth afterward.

With the surface prepped once again, I decided to be more careful about temperature and humidity when applying paint and primer. From this point on, I did all of my painting before 10am or after the monsoon around 5pm, when the temperature was between ~70F and 90F, and humidity was ~50%. I also applied the paint from a distance closer than the suggested 10 inches from the part. These two changes gave me a much wetter, more even coat, although slightly thicker. Note that in general, it's better to apply more, thinner coats. They'll dry faster and you'll get better adhesion. I started with the primer again since the sanding took some of the edges down to bare metal.

Then enamel, first coat.

I let the primer dry for an hour. I put the parts in a shoebox, and put the box in the sun, hoping to bake the enamel, hardening it and drying it faster, dust-free. I let the first coat dry for 24 hours before wetsanding with 1000-grit, looking for rough patches, as before, to knock down and smooth out. I avoided the edges, where the paint was thinner and sandpaper was prone to exposing metal. Then the second coat.

Here you can see bare metal on the back plate. I stripped off the leatherette, which was peeling away from the edge and making painter's tape difficult to apply flat. The cement was old and the leatherette came off in one piece.

I decided that this coat was smooth enough for my tastes. I could have waited again, wetsanded again, and applied a third coat for a finish even smoother than this. The weekend was over, however, and I knew I would be waiting at least 72 hours for the paint to cure enough for reassembly. They went back into the shoebox after 4 hours of drying in the garage. I handled them with a paperclip, avoiding pressing fingerprints into the still-gummy enamel. The shoebox was closed to keep dust and hair from sticking to the finish. They stayed there for 3 days, and I left them in the trunk of my car to bake while I went to work.

Please feel free to drop me a message if there's anything I can elaborate on. Reassembly is pt. 4.

[evanmayer]

kiev 4a tune-up, pt. 2 (paint prep)

Pt. 2 below the break.

After the trim was taken off, I started research for the painting process. The back was taped off since the brightwork was riveted to the back piece instead of screwed on.

Painting a vintage camera body is very much like painting a car. It’s hard to get apart, everything has old grease on it, there’s too much chrome, and prepwork is everything. I synthesized a process for painting my pieces from these sources: 

photo.net/leica-rangefinders-forum/00Wwf0

photo.net/leica-rangefinders-forum/00BGUE

Paint It Black! (archived site)

These Painting Instructions hosted by the Kiev Survival Site are probably the main source, except for the instructions on getting rid of the chrome. If for some reason you skipped those links, here’s the general idea (details and arguments in favor/against each method are above):

Nothing sticks to chrome very well. You have to remove it. In general, chrome plated camera parts are stamped brass, electroplated with nickel, which is then electroplated with chromium. This is really durable. Methods for removal range from cop-out (send it to a local body shop and pay the ~$40 mimimum for them to put it in their reverse electroplating baths), to dangerous (do it yourself with a car battery, a strip of lead, and a chemical bath), to less dangerous (chemically strip just the chrome).

I chose to use muriatic acid (~35% solution of HCl in H2O) to strip just the chromium off of the nickel. Although it’s commonly available at hardware stores for pH balancing swimming pools, this stuff is terrible for you undiluted (as you might imagine). Gloves and goggles in a well-ventilated area (my garage, with a fan) are an absolute must. An apron and respirator are even better. I used a coat hanger to manipulate the pieces in the bath. 

Remember in chemistry class when you labeled all of your chemicals? Yeah, do that here. HCl in H2O is clear, as is H2O on its own.

I cleaned the brightwork with lighter fluid and let it dry. Then I mixed my 31.45% muriatic acid in a solution with even more water. 10mL HCl, 30mL H2O. Always add acid to water. I chose plastic containers for everything. Using a coat hanger, I dunked the trim pieces in the solution. Depending on the strength of the solution, it will take a few seconds to a minute to get going. When it does, you'll know; small bubbles will form (H2 gas, flammable, no smoking, source: see reaction of chromium with acids). Another result of the reaction is your solution turning blue (see [Cr(H2O)6]2+ blue). I let each part sit for about 5 minutes, checked for remaining chrome, and dunked again if needed.

At this point, the parts don't look too much different. The stripping wasn't very even, but it doesn't matter, as long as all of the chrome is gone. Nickel looks slightly more yellow. Have a bucket of water nearby to rinse the acid solution off of the parts.

Now that you have a tray full of hydrochloric acid and heavy metal, you'll want to dispose of it properly. Don't dump it down the drain. Don't put it into your water table. Take it to a local hazardous chemicals drop off point.

At this point, I took the parts out back on my porch, and hit them with the brass wire brush of a rotary tool:

Then I dunked them in water to get any metal dust off, and wiped them with a lint-free cloth. Feel free to leave me a message if there's anything I can elaborate on. Painting ordeal in pt. 3.