I'll post some of mine in the sell/trade section soon. One thing I've realised is that older lenses and flanges can have well worn threads as the brass was quite soft. This means that measurements are tricky because the internal thread diameter will include some worn away brass. Not a lot but enough to potentially cause problems.
Sure, I could do the same. The tricky part is measuring the thread - any idea how to do that precisely?
Its worth reading this: http://skgrimes.com/library/faq/how-to-measure-threads but older threads can be worn so a bit of adjustment or tolerance has to be applied.
I have a couple of screw pitch thread gauges (search eBay with this and you will find some and they are not expensive - the threads on flanges I have look as though they are of Whitworth form - 55 degree thread angle). You also need a fairly powerful magnifying glass to view the gauge and thread. When I first tried I found it difficult, but going back several times seems to help and eventually you settle on the thread (tip = threads per inch) which you repeatedly decide is right. I'll post my spares and wants in the for sale or trade section but it would be useful to have a 'sticky' thread there about flanges. They are a real bugbear and expensive to get made new.
Thanks for the advise on the thread gauges; will buy some imperial/metric/us....Originally Posted by pgk
Indeed lateron the British stepped over to whitworth, but used different threads before. I have some info found on the later standardisation I will post.
Perhaps its best to start here a separate post on 'Mounting Ring Measures', and it might be made sticky by the moderators.
We could post there general info, and info on measures of mounting rings that already match the lenses members have in their collection.
Something comparable with respect to double bookform plate holders Ian Grant and I made a posting for: https://www.photrio.com/forum/thread...olders.171222/
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