Smooth Focus for USB Microscope

thingiverse

I love my DigiMicro USB Microscope! Focusing it used to be a chore, but since I created this little add-on, everything has changed. The focusing mechanism is finally within easy reach, and I can fine-tune the image in no time. Now I absolutely adore my microscope! The design of the bracket and worm was meticulously crafted using FreeCAD. The knob I chose was John Sanford's ingenious Parametric Knurled Nut Knob (you can find it on Thingiverse). If anyone wants to give this project a try, just let me know, and I'll be happy to share the source files. **Instructions** Printed parts: U-bracket (AdjMnt(repaired).stl) Worm gear (AdjScrew(repaired).stl) Knob (knurled_nut_knob (repaired).stl) Vitamins: 4 M4 nuts (Two lock the worm gear; two lock the knob) 2 M4 washers 1 M4x70mm screw (all thread) Assembly: Print the three parts. Attach the U-bracket to your microscope. You may need to trim the corners slightly to get a tight fit. Make it snug! Insert the screw into the worm gear. If needed, drill the hole in the worm gear out a bit; the screw should slide in securely. Enlarge the holes in the U-bracket so that the worm fits firmly against the grooves in the adjustment wheel of your microscope. Turn the adjustment slowly and don't overdo it – you'll have to back the screw in and out a few times to get this right. Remove the screw from the worm gear. Assemble all the parts onto the screw, ensuring that the knob ends up on the side you prefer. Place a washer, then slide the screw through one hole of the U-bracket, thread on a nut, followed by the worm gear. Tighten the worm gear in place and secure it with another nut as the screw goes through the opposite side of the U-Bracket. Drive the screw until its head meets the washer and the U-bracket. The worm gear should be centered over the adjustment wheel. Tighten the bolts on each side of the worm gear to lock it firmly in place. Add a washer to the screw, then attach a nut. Tighten the nut so that it's securely against the washer and the side of the U-bracket; then loosen it slightly to allow for smooth turning. Install the knob with the nut pocket positioned over the existing nut on the screw. Place the last nut on the screw and tighten it firmly against the knob to secure it in place. You can now effortlessly adjust the focus of your microscope!