M42 to M48 barlow lens adapter

thingiverse

Did you receive an M48 Barlow lens from Aliexpress? Did they send you an M42 lens instead, and then stop responding to your emails? Relax, this is a solution - an M42 to M48 lens adapter that works with my Amscope microscope. Print the adapter in PLA with 0.05mm layers, also known as Ultra Detail. The printer must be perfectly calibrated because the threads have extremely tight tolerance. Screw the lens on two turns, then back it off one turn, just like a tapping die, and repeat. This grinds out any irregularities in the threads. Be careful not to cross-thread the adapter because the plastic threads won't survive. Note: Fusion 360 doesn't have the correct threads in its standard ISO library. For reference, the two custom threads are M48x0.75 and M42x0.75. Standard metric threads go down to a 1mm pitch, but cameras for some reason use a 0.75mm pitch. I've uploaded an XML fragment with the custom threads needed. Follow this guide to install it. https://knowledge.autodesk.com/support/fusion-360/learn-explore/caas/sfdcarticles/sfdcarticles/Custom-Threads-in-Fusion-360.html