Mounting Brass Flange to (metal) Lens Board

[Richard K.]

I'm almost (almost but not quite) too embarrassed to ask this , but what is a good way to mount (brass) flanges to a Sinar (aluminun) lens board. Since aluminum is softer than brass, could one use brass screws into pilot holes or should the lens board be drilled right through and a nut and bolt used? Is there such a thing as a wooden Sinar type board so that wood screws could be used? Thank you!

[Oren Grad]

Dick Phillips used to make wooden boards for his cameras, which were sort of to Sinar/Horseman standard - those might fit.

But in fact, the only time I've needed to have a flange mounted on a metal board, I just sent it to SK Grimes and they did it for me.

< wimpy >

[resummerfield]

.....the lens board be drilled right through and a nut and bolt used?.....

I've had brass rings mounted to aluminum boards by SK Grimes, and they drilled completely through the board and used steel machine screws and nuts.

[Jim C.]

I wouldn't assume aluminum is softer than brass and vice versa, it depends on the alloy
of aluminum and the temper, I don't think aluminum lens boards are a 1100 alloy, it would be
too soft, it's probably safer to drill & tap the holes and use machine screws in the aluminum
board rather than wood screws.

[Kerik Kouklis]

Use machine screws and nuts. If you've not done it before, tapping small holes in aluminum can be tricky and can strip easily.

[Steven Tribe]

I have cut and tapped many holes in sinar boards - there is no need, or even room for an additional nut. I have seen a few reverse mounts. That is, with a countersunk hole at the back and a nut in the front in the countersunk flange hole. The former, normal, solution looks much better. The sinar alloy is quite suitable for making threads. There is only one size hole which is suitable for for a particular screw size and these in-between drill sizes can be difficult to locate locally. There are guides to correct hole sizes on the internet. Remember to reverse the tool direction after a turn to break off the cut edges.

[Stephane]

I also tap holes in the sinar boar (screw size is M3). I also shorten each screw to not stick out on the other size with a nut-cuter. I used 4 screws to hold a vitax very tightly. Professional look for sure.

[Steven Tribe]

M3 requires a drill bit of 2.5mm and M4 requires a 3.4mm hole.

[cowanw]

If you want it done professionally let me know.
Regards
Bill (from Hamilton)

[Richard K.]

Thanks everybody for all your good advice. Kerik, how about a Tim's © sometime?
My Sinar board with mounted brass lens (not protruding through the board opening) is to be mounted on a Sinar adapter board which in turn will be mounted on a Sinar Auto Shutter which in turn will be attached to a spacer/adapter which in turn will be attached to the front standard of my Chamonix or Ebony camera which in turn will be...
The lens to board to adapter to shutter looks kinda like this (that's not my lens! Mine is from 1854 and a lot smaller ) :
The first photo below shows the Sinar board to Auto Shutter adapter resting on the Auto Shutter (thank you Ducky in Hong Kong for making this for me!); the second shows a lens mounted via its flange on a Sinar board set into the adapter which is also attached to the Sinar Shutter. The whole kaboodle and kit is attached via a thin adapter to any camera with Sinar front standard...this system has the advantage of keeping cameras intact (unlike mounting the shutter in between the front standard and bellows) and also keeping your old barrel lenses mounted on their own individual board.

So, looking at the adapter, for my situation, I wonder if there's room for a nut on the other side of the board and maybe tap, screw and trim (if needed) would be better?