Form 2 does not print hole with 0.5mm diameter

Hello,

I have been trying to test the printer’s ability to 0.5mm holes but the lowest it printer was 1mm. I printed a cylinder, that has a height of 2mm, with 1mm and 0.5mm holes. The 1mm holes are printed all the way through, but the 0.5mm did not. I also tried to print three samples oriented along z-axis, tilted, and parallel to build platform – and all were the same. So has anyone been able to print down to 0.5mm and did they do anything special to achieve that?

Thanks,
R

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I have gotten the same results that you got when trying holes in this range. Which material are you using? It would be good to see how layer height (z resolution) affects your results. It would also be interesting to see what the hole diameter ended up being for your 1.0mm nominal hole. Is it actually 1.0mm or is it smaller?

what resin are you using? I am wondering if a less viscous resin might produce better results.

Layer height does have an effect on the ability to resolve negative features. You can usually resolve smaller holes when the layer size is larger. What layer size were you using?

Also print with a fresh tank and clean the optical glass. The more obstacle on the laser’s way, the more the beam is defused and less likely small details will print properly.

Another thing that will sometimes help with narrow holes is to flush them out with a syringe filled with IPA, as described on this page. That’s because viscosity can hold some uncured resin in the hole. Once the part is exposed to the light, that will start to cure.

I am using clear material on 25um layer height. I did not measure the actual diameter, will check that out tomorrow.

I am using clear material.

Good point! I printed on 25um layer height, I will try to print it on 50 and 100um. Thanks!!

Will do so! Thanks!

0.5mm holes will work in some cases but in my experience it’s hard to get them to work with thick sections. Grey normally works the best for me if I need small features.

I’ve also noticed that almost all holes are printed a bit smaller than intended. Straight holes like mold ejectors normally need a little bit of reaming to fit properly (this is normally done with the big industrial printers also).

I would say that they are probably printing the right size but there is still resin in the hole that needs to be flushed out prior to curing.

Chris

The centre of the laser follows the edge of anything that is printing, so that resin is cured on both sides of the edge. This means that for small holes the diameters have to be increased by 0.1-0.15 mm to compensate.

The same is true of parts that need to fit together in an assembly. The mating surfaces have to be moved to compensate for the width of the laser beam.

This compensation should be captured in the software. It’s not aggressive enough to correct the small errors that we’re seeing.

If you ever really really need something with super small holes and features, I recommend ProtoLab’s MicroFine Green material and printing service. It has incredible precision and I have gotten parts with 0.4mm perfect through-holes 15mm long. It is expensive though.

I needed to print bar supports for my models 1:87. The sphere has a diameter of 1 mm and the hole is 0.5 mm.

Wouldn’t turned brass ones be stronger and cheaper?

The brass is almost 10 times more expensive

Why do you print the railcar body in FUD?
Printing on your Form 2 is cheaper, more accurate, less stinky and no long-time risk of getting a silvery coating.

The railcar body is print with Form 2 (clear resin)