Adapting lens board

[Steve Bell]

I have a Super Angulon 65mm F8, currently on a Linhof recessed lens board, it came with a Technika 70. It's currently sticky at the slow speeds, and I'll have it serviced if I can use it on my Toyo 45A. I have a spare recessed lens board for the 45A, but it has already been cut for a larger Copal 0 shutter. Is there any easy way of adapting this recessed board with a 0 hole for a 00 lens? I know the lens doesn't quite cover 4x5 , but I would accept minor vignetting in the corners with no movements and take that into account when composing an image. Is it possible to obtain new blank Toyo lens boards, they are 110mm square. I'm in the UK, so local sources would be best.

Steve Bell

[David A. Goldfarb]

You probably can get a new blank recessed lensboard, but if you have no other use for your current recessed lensboard it's probably cheaper just to attach a metal disk or plate over the hole and drill it out for the 00 shutter.

[Gem Singer]

Hi steve,

Unfortunately, there is no easy way to reduce the size of a hole that has already been milled out in a metal lensboard. The recessed lensboard that you already have has a 34.7mm. hole for Copal 0, and you need a 26.6mm.hole for to mount your shutter. From what I see on their website, Robert White carries Toyo Field recessed lensboards, but there is no mention of the hole size. According to the Toyo catalogue, both blank and Copal 0 versions of the 12.5mm. recessed lensboards are available. Check with Robert White. Perhaps they have a blank one and can take your Copal 0 recessed lensboard in trade. Of course, you will have the extra expense of having a new blank lensboard milled for a 00 shutter.

[Vick Vickery]

There is nothing to gluing a thin (1/16" or so) piece of hardwood or aluminum to the back of the lensboard covering the hole and then drilling a new hole in the center. I have done this many times with no problems. I paint it black afterwards on the back and to match the lensboard on the front.

I have used epoxy and Liquid nails both as the glue, and prefer LN since I don't have to mix it. I always let either cure 24 hours before working with it. I usually also put a bead of black silicon around the inside edge of the old hole to make sure I have no light leaks.

Have fun, save $, and don't waste an old lensboard!

[martin howard]

Dear Steve,

You could try www.srbfilm.co.uk

Don't be put off by what you read on the web page. My experience with them, which was awhile ago, had to do with my darkroom enlarger and I needed some lens boards drilled/styled for durst. You never know, if you send them the 2 boards (the 'o' and the 'oo') I'd be very surprised if they couldn't/wouldn't do it for you. Best of all they are very friendly, helpful and well priced.

Best of luck!

[Jeff Dyck]

Hi Steve,

A few years back I purchased a blank recessed Toyo field board through my local shop to mount my 65mm SA in 00 shutter - I don't see the sizes listed for recessed boards in the current Toyo online catalogue, but at one time they certainly made a blank one. If you can't get one from Toyo, Canham's 4x5 boards are compatible with Toyo field cameras and they may have one available.

[Steve Bell]

Thanks for all the replies. I think I will mount the lens on an aluminium plate bonded to the Toyo recessed board. At first it looks easiest to mount this plate on the back of the board, as it is flat and smooth, but then the apperture adjustment ring would be clamped tight against the Toyo board front and would not move. Two thin spacers stop this happening with the Linhof board, but can't be done here. I can mount it on the front, but then it has to cover a circular raised area, possible, but more awkward to cut. I will either scribe slighly undersize re the lens mouting hole, drill multiple holes inside the scribe, then carefully use half round files to acurately open up the hole. I have done this many times in the past mounting meter movements etc in electronic projects. I also have a selection of punches that are clamped to each side, then tightened to cut out the hole, I'll check to see if any are close in size. The locking ring needs a hole slightly larger than the lens, as it has a lip that drops into the hole around the thread. All I need to find now is an adapter so I can attach the cable release, the recess stops this.

Would having the lens mounted slightly forward about 1/8 inch make any difference to focusing, the Toyo takes, I think, lenses down to 47mm with this board, so 65mm isn't at the end of its range. I suspect and hope not.

It's useful to know Canham lens boards are compatible, I didn't realise that.

Steve Bell

[Jeff Dyck]

Hi Steve,

Just came across the board you are looking for (a blank deep recessed toyo field board) on "that auction site" - try searching for item 3856370683. Good Luck.

Jeff

[Steve Bell]

Jeff, yes, thats the one, and blank. It's a 'post in USA only' item and I'm in the UK. I've started marking out a blanking plate.

Steve Bell