Betax No. 4 lensboard size?

[guyatou]

Hello all --

I just picked up a cheap 13" Wollensak Velostigmat f/7.5 in a (supposedly) working Betax No. 4. Hasn't arrived yet, but I'm on the hunt for a lens board. However, I can't seem to find what size hole I'll need. Does anybody happen to know?

I've checked all the usual places (here, Grimes, etc.) and have found some dimensions, but not the lensboard hole size! AARGH!

I have a Toyo 45GX and a Busch Pressman D. Will fit the lens to one of them (probably the Toyo, as the Pressman has limited bellows throw, and the Pressman boards are tough to find.)

Cheers,

MD

[Jon Shiu]

The hole will need to be large enough to clear the raised shoulder of the flange that sticks out the back of the flange into the hole. The flange is mounted to front of the lensboard. The diameter of the hole is at minumum about 69mm, but can be much larger as the wide flange covers up any gaps.

Jon

[guyatou]

Thanks! I just found a link which may help answer my question further.

For others looking for information on Betax lensboard sizes, I found this old Wollensak catalog. http://www.cameraeccentric.com/html/...lensak_15.html You'll find the info under "Dependably Accurate Shutters."

Looks like 2-19/32 (65.88mm) inside flange diameter on the No. 4. So, that would be the size I'd need to drill, right?

[Jon Shiu]

That is probably correct, but like I say you can go a few mm larger just to maker sure it fits in.

Jon