Sounds like an interesting design. I went with simplicity with my design since the the film holder frame detaches from the back frame. Then I just rotate the film holder frame and re-insert it into the back frame. The film holder frame is held to the back frame by the two thumb screws as I talked about below. I just put the metal inserts into the back frame tonight and it works great! All I have to do is turn the knobs. It makes the design light and simple (I like the old attage KIS (keep it simple)). I like the idea behind your design though. I think the slider between the wood would be a good idea though, since the wood would tend to expand and contract depending the tempurature and humidity of the environment.
----- Original Message -----
From: Bradley M. Small
Sent: Saturday, January 27, 2001 8:10 PM
To: [EMAIL PROTECTED]
Subject: Re: [Cameramakers] rotating back
Dan --
What I was considering was somethign liek this:
Start with 2 squares of equal size maybe 7 or 8". Cut a center circle in both of them same size as the OD of a large pvc pipe (6"?). I figure taking a slice about 1/4" thicker than the two boards put together. Then epoxy it into one of the boards. Place the other board over it and make a retaining ring out of 1/4" plywood, perhaps about 3/4" wide and epoxy that on the exposed end of the pvc pipe. This ould make a rotating back. I was thinking about how to adjust it, and the idea of putting a bullet catch in one of the boards, and a hole in the opposite at two 45 degree points as detents. Of course perhaps just a threaded hole and a nylon thumbscrew. I am also not sure about the wood on wood, and may also consider some kind of nylon sliding material on one to keep the friction down.
Just thoughts, not sure how much it will add to size and weight, but fortunately that is not a major concern to my current design.
-- Bradley
----- Original Message -----
Sent: Friday, January 26, 2001 11:19 PM
Subject: Re: [Cameramakers] rotating back
Bradley,
I found that (at least with the design I'm using) I have a 3/8" ledge on the rotating back. This allows me to use a small threaded insert that is 7/32" wide (I bought small wooden knobs from my local wood crafters shop and removed the threaded inserts) that I can install into my camera frame at the top and bottom. I'm going to turn some knobs to match the camera and use these as pinch screws through the frame. When I want to turn the film holder frame from landscape to portrait I just loosen two thumb screws and turn it! Since the threaded inserts are made of metal I never have to worry about the wood stripping out. As soon as I get these plans drawn I put em' up on my web site (a day or two). Will that help your problem?
Cheers!
Dan Rhoades
----- Original Message -----
From: J. Wayde Allen
Sent: Friday, January 26, 2001 8:32 PM
To: [EMAIL PROTECTED]
Subject: Re: [Cameramakers] rotating back
On Wed, 24 Jan 2001, Bradley Small wrote:
> I am thinking about whether to do a remove-and-rotate vs actual
> rotating back. I have been debating a design, but haven't had the
> chance to research the materials yet. What I am thinking about is 2
> squares with an equal sized hole Iam guessing about 6" or so, that I
> could epoxy a slice of pvc pipe into one and "somehow" clip it to the
> other and use a bullet catch for a detent or possibly an index pin
> instead.
I've thought about doing something similar to this before. Never tried it
though. You'll have to let us know how it works out for you.
> The question I have is with size. At what point does a vignetting
> problem occur?
I think we've kind of already answered this one.
- Wayde
([EMAIL PROTECTED])
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