Want to build 8x20 rear frame and back

[bvaughn4]

I have a decent Korona 8x10 view camera frame I'd like to convert to 8x20. Does anyone have any drawings for one you have built from scratch. Plan to use the front standard and rails as is, hoping just build the rear frame and back. Will most likely purchase an 8x20 holder and then build the back to it.

Thanks in advance for any drawings, suggestions or tips.

If you have a drawing to email, my address is bvaughn4 at knology.net.

Thanks!
Bill

[ypres.bass]

why you don't build a new one 8x20. and after that your Korona can move on to my house, can it? :-)

[Jon Shiu]

Perhaps just build a large rear extension box. What type of holder will you use, vintage or new?

Jon

[Jay DeFehr]

Bill,

I think you're on the right track; holders first, then back to fit the holders, frame to fit the back, and bellows to fit the frame. There are lots of very knowledgeable and proven camera builders here, and I hope some chime in with advice. Good luck on your project!

[bvaughn4]

I have read a bit about the extension boxes. I guess part of the thought is I'd like to have a go at making the read frame that looked like it was original. I suppose I'd use a new film holder. Could only afford one at the rate they go for! Have toyed with the idea of disassembling one of my 8x10 wooden holders and using it as the model to scale up! Have most of the rough tools I need and access to a shop when finer precision is required.

Stanislav, I got the Korona off eBay for a song. Was after the rear extension for use on my "better" Korona 8x10 but the photos weren't good enough for me to see that they were slightly different. When it came, I decided it was too good to junk but not worth a new bellows to just sit on a shelf.

[Len Middleton]

I suppose I'd use a new film holder. Could only afford one at the rate they go for! Have toyed with the idea of disassembling one of my 8x10 wooden holders and using it as the model to scale up! Have most of the rough tools I need and access to a shop when finer precision is required.

Not certain if you are aware that there more than one common version of 8x20 holders.

I recently purchased a 8x20 project from a member here and sent the the holders and back to Richard Ritter to have darkslides made for the holders, but also for him to check to make certain they all worked together. Money well spent...

[John Jarosz]

I built my 8x20 from (2) Kodak 2D's that were basket cases. The front standard, front & rear rails, center block were refinished. The bellows was purchased from ebay. It was much longer than I needed but in time that may permit me to use very long lenses. The back was made by using the filmholder dimensions to start and the rear bellows frame size was based on the size of the rear of the bellows. I did not make any formal plans, everything was worked out on-the-go in the shop. Having two sets of brass hardware allowed me to essentially duplicate the geometry of all the rear controls in the wide format. The back and rear frame were constructed as one piece, that is, the GG back does not separate from the rear frame. Doing the back in this manner allowed the back to be of much more solid construction. I didn't see the need for having the ability to remove the back from the frame. After two years of use I feel all my assumptions on the design were good and I have no plans to change anything. Get an S&S filmholder and begin sketching out a solution. You can use all the existing design details on your existing camera, the back is simply wider. I don't recommend attempting to make filmholders unless you are a master woodworker with professional grade equipment (my opinion). Making a relatively thin wooden structure such as a filmholder presents untold challenges in preventing a warped structure or one that has the flatness of a potato chip. It's enough of a challenge to make the back flat. As you work thru this, feel free to PM me if you think of specific questions.

John

[John Jarosz]

One more thing I forgot.

Using the Kodak 2D rails and standards, I felt the structure of the rails were not strong enough to support the weight of lenses suitable for 8x20 or the weight of the back, filmholder and a much larger darkcloth, to say nothing of being able to resist the 'sail factor' on a windy day. So I built a strut of maple that was mortised into the tripod block that also supports the front and rear rails, The huge bending moment placed on the front and rear hinges that permit the rail to move is then removed and the camera works as if it is standing on a large table. It's an extra piece but well worth it.

John

[bvaughn4]

Thanks for the input John. I like your idea of making the back non-removable to improve stability. I'm pretty much in agreement with your assessment of making my own holder. Not a master wood worker... As for the strut you mentioned, the Korona has some slots cut into the tripod block with some half washer looking metal reinforcements to allow reinforcing struts - one on either side to help support the weight at longer extensions. Actually, a pretty neat and clean solution.

Len, I figured as much. Ran into that problem with an 11x14 and ended up making a new back to adapt to the mis-matched holders I acquired separately.

Thanks again,
Bill