It's not my favourite wood, but it's interesting. It's not too heavy, it's dense enough to machine, and it comes up lovely after sanding and a few coats of finishing wax.
Neil
It's not my favourite wood, but it's interesting. It's not too heavy, it's dense enough to machine, and it comes up lovely after sanding and a few coats of finishing wax.
Neil
It's getting to the assembly stage now. First, the bellows are glued to the frame I made yesterday, which has been painted matt black to assist the light trap. Many tiny bulldog clips hold the fabric flat (it really didn't want to lie flat; it's been sat with a crease in one corner for a few years).
And other parts require black paint - the back box face facing the ground glass, and the back plate itself on the forward face. I could spray it all black, but I want the wood visible where it can be, so lots of masking tape is necessary/
Another design change to do: the original drawings showed a sloped back to the base plate; I think instead I will chamfer the matching edge of the back box, which involves less planing and will probably be stronger overall - certainly easier to implement.
Still to do:
- cut the hole for the lens in the base plate
- make the brass struts to link the base plate and back box (and fit them)
- fit the focus rack and gears
- find some focus knobs
- wax on, wax off - for ten or so layers over a few days
- reassemble everything
- push the button
I think I need to consider some mechanism to lock the extension, too, and maybe the focus, but let's see.
Neil
Things painted black in all the light traps:
Trial fit:
Fiat Lux!
The hole in the base plate is cut, which was quite, um, interesting; I don't think I have the best choice of hole cutter. The part where it cut through, rattled the base around, and launched the cutter and the chuck from its morse taper on the drill was perhaps the most exciting, but everything seems to have survived.
Still thinking about the best way to implement the lens board clips.
Neil
Wow. You really know how to use a Unimat.I have, amongst others, a Pultra 2" centre high lathe so I can imagine the patience that took. I hope you get a Bridgeport for your birthday. And a piece of floor big enough to put it on!
I'm sure the folks that designed it all those years ago would have heart attacks if they could see me with it, Sean. Though one of the big problems is backlash in the threads; I've taken three attempts to produce a decent strut this afternoon. It tends to pull itself off line a little.
Never mind, here's today's efforts. First, the focus racks are glued in place - nothing fancy, just Bostik general adhesive and weights overnight.
A makeshift jig to drill the pinion and the focus drive shaft:
and the pinion in place, fixed with a bent bit of wire.
Finally, the single strut I completed today; it's indexed to get the default right angle, but also allows the back to be tilted both forwards and backwards (or allows the bed to drop, depending how you look at it) and also holds the box closed.
Pictures this week?
Neil
The second strut is completed, but I may need to move the struts forward a few millimetres - there's a little bit of droop in the tailboard. Fitted the tripod mount (3/8th) but I may fit another on the baseboard; it's a long way back and there's a lot of load on the front of it though it does seem stable.
Worked out how to hold the lens board in. Not terribly elegant, but it'll do for now.
Almost complete, on a tripod:
And with the box closed, to show the lens poking through:
The total weight, with lens, is 1.5kg; just under 1.2kg without the lens.
Still to do: some sort of locking for the extension track - I think some sort of off-centre disc - and a latch to hold things closed, and the focus knobs.
Neil
I'm rather pleased by this, even though it took most of the afternoon to do - it's a little fiddly, but it works well.
Neil
Still waiting for the focus knobs, so, er, I didn't bother and went and attacked St Alban's Cathedral this afternoon. The negatives are drying as I write.
Neil
Hmm. Some pictures, and some thoughts...
1/ The images are all soft. I don't know why, but I *suspect* that it is because the idiot taking the pictures forgot to take the cable release for the lens, so had to hold the release during exposure - and as the interiors were four and eight seconds, it's likely there was movement. I don't think that the lens was being pulled out of focus, as there's no obvious focus plane in the nave shot. Further investigation to be made.
2/ The bed needs a redesign. The shortest lens it can focus to infinity is likely to be a 135mm and I would have liked a 90mm to be usable. This is because of the unused space at the back of the bed which isn't really necessary except as somewhere to fasten the hinges. A redesign will be required to fix that.
3/ Some sort of handle for the ground glass will ease lifting it away from the focus plane to push the film holder in, but the spring strength is fine.
4/ The diagonal braces that hold the back suffer a little from their position; they need to be further away from the hinge for better stability. There's also a little movement in the fixing bolts through the wood; a better approach would be to mount something on a metal plate.
On the whole, I'm pleased. The camera is only half the weight of the one I have been using, and it folds up smaller. I don't think the focus is an issue, but I'll know later - at at present I don't have a 90mm lens
Neil
Great work, Neil, and with those tweaks you'll have a worthy camera. Well done.
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