Issues mounting Nikkor-w 300/5.6 in Toyo field lensboard

[gthomas]

Trying to mount a Nikkor-w 300/5.6 in a Toyo field lensboard, and I'm running into two issues.

Issue 1 - What are the 4 small holes drilled into the lensboard and how do I plug them?


Issue 2 - I cannot get the lock ring to actually do its job. I'm a LF newb, so I may be doing something wrong here ... I separated the front and rear elements and put the front element down. I then put the lensboard over the front element and tried to tighten the lock ring. It tightens, but due to its shape (like a top hat), the lens is not actually secured to the lensboard.

 

[Dan Fromm]

I have some boards that were drilled so that solenoids could be attached. I cover the holes with darkroom tape. Electrical tape will do too.

Try turning the retaining ring over.

 

[gthomas]

Thanks Dan!

 

[shutterfinger]

Black silicone rubber for filling the drilled mount holes. For a permanent fill use JB Weld. Tape is fine for a temporary patch. +1 for turn the retainer ring over.

 

[mike c]

It is hard to tell form the pictures, but there is something fishy about the hole in the lensboad. It looks to small or out of round, the locking ring has a little shoulder on it and that what sits in to the board.You might have the wrong locking ring maybe.