RogueRose - 1-10-2018 at 14:21
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:
https://www.sks-bottle.com/CapNeck.html
http://www.usplastic.com/knowledgebase/article.aspx?contentk...
http://www.qorpak.com/pages/howtoselecttherightsizecapforyou...
Here is a link to the Qorpak measuring tool - it is printable - I included an attacked copy of the PDF
http://www.qorpak.com/contentimages/Qorpak_CapMeasurer.pdf
Here is the page to request a cap measurer from Qorpak if anyone is interested in that.
http://www.qorpak.com/pages/capmeasurer?utm_source=Website&a...
Here is a good link that describes the different types of liners used in caps, could be helpful if you have a stubborn solvent or compound:
http://www.qorpak.com/pages/ContainersandClosuresCapLiner
Here is a short 90 second video link to measuring the cap/neck
https://youtu.be/SHvjPjLnDCY
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)
Here is a link to the thread measurement PDF - which is the last attachment.
http://www.bellcoglass.com/sites/default/files/kcfinder/file...
Attachment: Qorpak_CapMeasurer (1).pdf (1.3MB)
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Attachment: Thread Finishes.pdf (3.3MB)
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