Where do I get large retaining rings?

[jcc]

Does anyone have any leads as to where I can get a 80mm/0.75 retaining ring, for an Industar 37 300mm f/4.5 lens? I've googled different combinations of words and can't find a vendor. Does something like this have to be CNC machined?

 

[AgX]

One does not need a CNC machine to make a retainingh ring. Any lathe added by a simple drill would be sufficient.

 

[Alan Gales]

Have you tried S.K. Grimes? They make flanges and retaining rings.

 

[Ian Grant]

Look for a lens flange, they areen't the same as a retaining ring and screw to the lens board itself.

Ian

 

[AgX]

Are flanges more eays to obtain than retaining rings?

 

[Ian Grant]

Are flanges more eays to obtain than retaining rings?

In larger sizes retaining rings are rare and probably not strong enough for the weight of some large heavy lenses so flanges are used instead.

Ian

 

[AgX]

I see your point. I did not consider a mechanical issue. Yes, flanges can be advantageous, though the effect depends on the material of the lensboard.

 

[Ian Grant]

The Industar 300mm f4.5 lens should have a flange, that's what they normal sell with.

Ian

 

[jcc]

That's it, a flange! Excuse my limited vocabulary on the subject. I meant flange.