4 ms·

3d printing is amazing but it is not extremely precise. At the end of the day you are extruding plastic from a stepper motor controlled head not much different

3d printing is amazing but it is not extremely precise. At the end of the day you are extruding plastic from a stepper motor controlled head not much different than extruding glue from a glue gun (I know about other mechanisms but this was done with an extrusion printer) . You have many factors at play such as the acceleration rate of the heads, the extrusion rate and how it ramps off at the end, how true your axis are, mechanical play... it is endless how much you can tweak. And at the end of all of that you are not going to make anything that has micron or even thousandths level precision. For something like a lens, machined metal and at a minimum injection moulding is needed. It would be as if I said I could produce a gauge block to measure 10mm for a fraction of the cost. But for that cost savings my precision will be unusable when my block is not flat and is 9.956 mm which in 3d printing would be very close but in machinist land is off by a mile. Lens casings and aliignment need similar precision.

PaulHoule 4y ago
when I was a kid I remember buying lenses from Edmund Scientific and making telescopes, microscopes and similar things by cementing lenses into cardboard tubes. The results weren't great but they were workable.
dekhn 4y ago
nobody makes perfect lenses as part of the initial manufacturing method. Lenses are always smoothed/polished. In the 3d printer case (hobbyist) you would 3d print a solid object oversized, then sand/polish it down. The automated microscopes I build are mostly 3d printed parts. The precision doesn't matter much- I always have to add additional hardware to adjust the precise positioning (typically screws going through 3d printed threads). But you are right there are definitely other methods which work faster and cheaper and ten thou is a typical target for a good machinist.

PaulHoule 4y ago

when I was a kid I remember buying lenses from Edmund Scientific and making telescopes, microscopes and similar things by cementing lenses into cardboard tubes. The results weren't great but they were workable.

dekhn 4y ago

nobody makes perfect lenses as part of the initial manufacturing method. Lenses are always smoothed/polished. In the 3d printer case (hobbyist) you would 3d print a solid object oversized, then sand/polish it down. The automated microscopes I build are mostly 3d printed parts. The precision doesn't matter much- I always have to add additional hardware to adjust the precise positioning (typically screws going through 3d printed threads). But you are right there are definitely other methods which work faster and cheaper and ten thou is a typical target for a good machinist.