Camera turned out well, but though I would compile a list of the things I wish I could do over- and probably will have to do over at some point. Will update the list as new ones are discovered.
I cut the shaft flush with the bed, and tapped and Locktite’d 6-32 studs into each end for the focus and lock knobs. Would have been better to leave the shafts long on the focus side and pin the knobs to the shaft, as done with the gears themselves. The studs are fine for locking knobs, but probably too weak to handle the torque from the focusing knobs over time.
Should have made the rear bellows frame thicker to give a little more wood around the hole for the knob’s retention pin. Alternatively, I could have just located the pin in front of the frame to lock it in place. If I ever over extend the camera and put a lot of stress on the bellows, the pin may break through the weak side of the frame. Not a huge worry, the fabric’s bond to the frame would probably fail before the wood does, but I may inlay a piece of aluminum to reinforce this. Might have been better to locate the pin towards the front of the bellows frame, and just file enough of a divot in the frame so the pin would wedge the frame tight to the back.
Friction fit for the gear racks. I haven’t come up with a good way to mechanically fasten these small brass racks to the extension. Too fine and too small for screws, at least the size of screws that I can handle with my ham hands. Friction is fine to keep them from simply dropping out, but not good enough to resits linear movement under a lot of load. I inlaid these gears with high quality double-stick tape, which works ok. I usually use stopped dadoes for the racks, so the racks are captive front to back. But for a bed this short I wanted every bit of rack I could get. As is, it works fine under regular load, but if I ever try to focus with the movement locked down, it just might force the gear out of its groove. I might get some micro drill bits and just pin the rack to the wood in a few spots between the teeth.
As also shown in the picture above, I used stock black oxide steel T-nuts for the rear shift. They’re a little grabby, will probably make some out of Delrin. The head of the stainless steel screw takes all the load, the T-nuts are just to keep the screw from rotating when tightening/ loosening the control knobs above.
I did pretty well locating most of the screws considering the space restrictions. But the screws in the aluminum angles on each side of the bed are meant to easily adjust the tension on the rear extension- except I can’t reach the front and back screws without removing the focus and lock knobs.