It is necessary to make an adapter ring for connecting the smartphone to the microscope eyepiece (turn from ABS on a lathe, or 3D printing). Microscope eyepiece diameter is 33mm. What should be the internal diameter of the ring (tolerance/clearance gap) for proper connection of the eyepiece and adapter ring?

enter image description here

  • $\begingroup$ What dimensions would make it useless? What does it need to fit on? Adapters tend to have two interfaces that they "adapt" - what are dimensions of those? Is there any threading involved? $\endgroup$
    – Abel
    Aug 29 at 12:05
  • 1
    $\begingroup$ Depends on the material, and how much force you want to use to apply and remove the eyepiece. Simplest way is to make some test rings with different IDs. $\endgroup$
    – Drew
    Aug 29 at 21:23
  • $\begingroup$ @Abel It should be fit on the outer surface of the eyepiece tube. Eyepiece diameter 33 mm. The eyepiece tube is smooth, without thread. The outer diameter of the ring will correspond to the diameter of the holder. $\endgroup$
    – minto
    Aug 30 at 10:22
  • $\begingroup$ I suggest you figure out a max acceptable angular error, and use the length of the eyepiece that your part will cover to then determine the max gap between the 33 mm and your part - the longer your part, the smaller an angular error you can achieve with the same gap. Another consideration is force, especially if you aim for a press fit. How much force at your contact points does it take to bear the weight of the phone and someone pressing to capture photos? How much does it take to stretch your part to 33mm? $\endgroup$
    – Abel
    Aug 30 at 12:54
  • $\begingroup$ Adapter ring height is 28 mm. Regarding the force that must be applied to put the ring on the eyepiece: normal fit, without undue force, but without the adaper ring dangling. $\endgroup$
    – minto
    Sep 1 at 13:16


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.