It's amazing how well it fits together on the computer and how bad I am at cutting straight lines and correct thicknesses! I'll be working on this later this week when I return home.
I'm having a rethink on mounting the back plate in H and V orientation based on Tim's comment, but it's not on the critical path.
Here's a Tinkercad view of the struts: I might splash the nine quid and see how (in)flexible the material is. https://tinkercad.com/things/hb6n9j2aRuQ
Neil
A little shiny bit. These are the supports for the front standard; they tilt back to match the dropped bed. The lens both pivots and slides in the slots (some of which are straighter than others, ahem). I may need something more complex between the lensboard and the supports to lock the tilt; still thinking about that. It might be a case for some 3-d printed plastic.
Neil
More shiny... I do believe we're getting there.
A sneaky way to keep the lens board vertical, unless I need to tilt it: I cut 3mm discs from 19mm / 3/4 inch round bar and milled 10mm (a bit over, actually) slots in them, 0.5mm deep (20 thou). The centre hole is tapped for 3mm bolts which bolt to the angle and will then pass through the slotted risers. Most of the time, just using rise/fall, this keeps things parallel; if tilt is needed, then the thumbscrews are released that extra turn and the whole lensboard can then tilt.
The angle is then superglued (cyanoacrylate) to the lensboard which locks everything in position.
Everything is screwed to the extension traveller:
And everything even fits in the box. The only problem is that the guides are now a quarter inch too thick... I need to think about that. Change the bellows mounting, perhaps.
Neil
Removed the front bellows frame (per the earliest posts here) and glued it to the front standard; many tiny bulldog clips hold everything in place until the glue dries. The glue will let me salvage the bellows in future, I think.
And finally we have something which, at dusk and with the light behind it, might be mistaken for a camera.
Rather annoyingly, I can't find my 1/4 Whitworth tap, so I can't make the tripod mount and I may use a 3/8 that I made for a previous camera. I did want to use the pan and tilt head I have, though, which has 1/4 screws and a 3/8 hole to fit the tripod stem. I might just stick with 3/8 and find a 1/4 - 3/8 adaptor; at least that way I can use it with or without the head, which has nice weight implications.
Neil
Great work, Neil, despite the reservations you have about your ability. I've been following your progress with interest for my own future building plans. I'm wondering if you've made a decision yet on whether to glue or pin the pinion gears to the shaft? Obviously with modern glues a glued joint would be pretty permanent, but I wonder if pinning would be better to allow for later dismantling for repair etc. On the other hand, pinning would be difficult to do with precision. A grub screw would be the ideal solution, but not with delrin gears, I think.
Neil, it looks real nice. I'm wondering whether the front hides inside (there are hinges)....in order to flip the rail portion up to close the camera ? I presume this has been worked out in your plans.
Les
@Barry - still not decided about pinning or glueing. There are difficulties getting access to the pinion in place in either case but I think it might have to be a 'soft' glue like a contact adhesive. I think once the pinions are in place, there they shall stay!
@Leszek - there is the hinge that you see and another at the other side, which allows the to pivot and the bed to lift once the front standard slides back off the guides. It's a part of the design I'm not totally happy with, to be honest, but it seems to work.
Today's effort - after seeing it yesterday, it all comes to bits again. Bet you weren't expecting to see that angle cramp again, but this time it's for a flat bellows frame to which the bellows will be glued, and will then bolt into the camera back, saving a couple of millimetres in depth.
Attachment 147836
Made the first lens board - two sheets 2.5mm thick with suitable holes for copal 0, laminated together with the grain at right angles for strength. The inside is sprayed matt black.
As is the light trap of the front standard:
Neil
You camera is coming along nicely, good job. Where did you get you bellow?
Roger
Oh, Custom Bellows some years ago. Yeah it helps to actually read the thread.
Roger
Very nice. My current 5x4 build is also sapele, although I usually refer to it (wrongly) as mahogany when explaining it to people.
Steve.
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