Determining bottle thread / cap size - What is the best method & some charts & tools available
I've been having a little bit of a difficult time finding the right caps for some of my bottles. One set of 8oz boston rounds had caps that seem to
fit almost perfectly on some 75ml tapered test tubes but even though they look like they fit (basically same diameter) and screw on, the test tube has
about an extra 3/4 of a turn in threads (they are longer) and the threads are just a smidge wider. The caps work for a semi-working fit, but if liquid
is placed in it and the tube is shaken, it will leak.
I did find a couple pages that give some guide lines on how to identify neck size:
I also attacked a copy of the thread finishes file which could be helpful as some bottles have very high thread counts (think reagent bottles with
GL45 caps)
