Lens Flange Exchange

[Tim Meisburger]

I have a few old flanges laying around that fit nothing, and a (good) few lenses lacking flanges; and my guess is that quite a few members could say the same. It would be great if we could set up an exchange, where I could trade my useless flanges for your useless flanges. I thought about establishing that as a thread here, or possibly in the For Sale section, but realized it would be difficult to keep up to date because you cannot update old posts. Ideally it should be a user-editable table, so when things are traded they can be removed, but I'm not a computer guy and don't really know if that is possible on the forum or if you would need another website.

Also, we would need a protocol for measuring, and participants would need a thread gauge and calipers.

What think ye?

[Amedeus]

Great idea ... formatting and updating can indeed be a challenge ...

[Jim C.]

Sounds like a great idea, but measuring can be a chore since some flanges don't
quite fit the usual suspects ( whitworth, metric, inch ).

[jcoldslabs]

I, too, have flanges that don't fit what I have as well as lenses without flanges. But I agree that tracking it all could be tricky. I'm in if there is a way to make it all work. Worse case we all exchange some flanges and end up where we started, without any that fit. Best case, we all end up with the flanges we need.

Jonathan

[Jon Shiu]

How about list all your extra flanges and those you are looking for in the For Sale sections and worry about the details later?

Jon

[Tim Meisburger]

Okay. This weekend I'll measure everything. My plan to get needed flange size is to measure diameter with calipers, then to determine the thread of the lens with a thread gauge, and subtract twice the depth of the appropriate thread to get flange ID. If someone has a better idea, I'm open!

Cheers, Tim

[Steven Tribe]

I have always found measuring the gauge of the short male thread on lenses to be very difficult compared with the female thread on flanges. Especialy depth. My experience of buying odd flanges is that it is better to buy slightly undersize flanges and "trim" using a hand held thread tap. It takes quite a long time, but a tap is a better way of checking clearance/depth than a thread guage. I have done over 6 flanges with this method. Works with both aluminium and brass.

[Vincent Pidone]

I think that the Grimes web site has some information on how to measure threads for flanges.


edit: http://www.skgrimes.com/library/faq/how-to-measure-threads

[Tim Meisburger]

Thanks Vincent. That is very useful, and I will use it when I measure on Saturday.

[Jim C.]

Thought I'd add some proposals for measurement guidelines, aside from the
usual ID in mm and thread pitch, I'm not quite sure what to call it
but a measurement of the 'return' of the flange might be helpful and
whether it's brass or aluminum material.

95641

[Tim Meisburger]

Just a note to report I have established the Exchange on the For Sale section.