Summary

openscad version of the eyepiece/objective tube from kwalus' microscope.

Instructions

made in order to fit the following lenses (but since it's parametric it should be easily adjustable for other lenses of course):

https://www.thorlabs.com/thorProduct.cfm?partNumber=LA1560
https://www.thorlabs.com/thorProduct.cfm?partNumber=LA1540

I only printed the tube so far, and with a bit of lighting from below I get a good picture with one LA1540 in the objective part and one LA1560 in the eye part. hopefully I will be able to add another LA1540 later for better magnification.

update: I added another 1560 in the eye part, plus the following led light source:

http://www.amazon.com/TEKTON-7476-Compact-Worklight-2-Piece/dp/B000NPPBYM/ref=sr_1_1?ie=UTF8&qid=1372254847&sr=8-1&keywords=tekton+led

this together gives quite good magnification and clarity. though not as good as when I replace the light source with a 50W halogen lamp (which almost melts the microscope).

Parametric Tube for Kwalus' Microscope