Asanuma project camera – 4×5 insert nearing completion

In the last two days, I’ve made same progress. Yesterday, I ground some glass for the back:

IMG_1184

Messy, but effective. I use a lapping glass and 500 grit silicon carbide lapidary grit. Light pressure, lots of rinsing and checking. I cut the glass to fit the back. No clipped corners on this one.

I then installed the springs:
Getting closer...

The springs are surface-mounted; this first pass, I left the turned ends proud of the surface. I thought I’d see how they worked, and if too tight, I’d create recesses for the ends later. I used 3/4″ x #17 wire brads as mounting pins; just set the frame in place and press the pins in to mark their locations.

IMG_1185

Predrill the holes so as not to split the wood, cut off the heads of the brads, and tap them in place. And it worked well. Except the springs applied too much tension as installed. I needed to recess the ends. Easily done with a Dremel and straight bit.

After recessing the ends and playing with locations a little bit (some tweaking is always required), the back is working as planned. Here ’tis, with a film holder inserted:
IMG_1190

IMG_1191

An appropriate amount of force is applied to the holder, but there’s easily enough flex left in the springs for removal.

I have only a few more things left to do before applying finish: Cut the hole for the plate back’s locking tab, ease the back of the ground glass holder grip to make grabbing it a little easier, and maybe rout a recess under that end in the insert to facilitate even easier insertion and removal of the holder, pending a bit more testing. Finish sand, ease the edges, and apply tung oil finish. Wait a few days, lacquer, and it’s done.

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5 thoughts on “Asanuma project camera – 4×5 insert nearing completion

  1. Scott, that looks great. Thanks for sharing the details and documenting it so carefully. What was the source of your springs?

    Also, have you considered carving finger grips in the edge of the gg holder? You mentioned easing it; a gouge with a fairly small sweep might make some nice grips…

  2. Thanks, Bob. The springs came from a tattered old Graflex spring back that had already been parted out. Which was good, ’cause I hate making them, and these look better than i could ever make.

    I have some gouges that would work (think they’re 5 and 7 sweeps), but I never have luck carving cross-grain like this would be. Maybe I need to practice that a bit before I default to an eased edge…

  3. Thanks — thought it looked like a set of Graphic back springs, as I just picked my first beater Crown to play with.

    My guess on the carving is that you’d want to do the carving strokes with the grain, a la chip-carving, rather than across. But I’m not a carving expert. If it were me, I’d definitely practice on some scrap first. Nice thing about cherry is that it’s soft enough to carve pretty easily, most of the time.

  4. Is the polishing grit you use the same stuff as is used to polish rocks in a tumbler? If so, I bet I have some and in different grits as well. Once I get done butchering the wood on this project I can damage some glass for my next trick 😉

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