Exposure time

Exposure time is how long each layer is exposed to UV light during printing.

It is not something I have worried about much because the default settings seem to work fine. I am using Elegoo resin in an Elegoo printer, and Chitibox has built in settings for that. The only thing I have adjusted is to increase the exposure of the bottom layer slightly to help adhesion to the build plate.

If exposure is too high, you will get fatter pixels and hence loss of detail. Some recent prints were supposed to have a small hole through them for wires to go through, and this was getting blocked, and i wondered if high exposure was the problem.

If exposure is too low, you will get thinner pixels, and possibly loss of structural integrity. Some places recommend reducing exposure for small, detailed models, and raising it for larger models.

I found a calibration STL by AmeraLabs here.

The default exposure time for my system is 2.5 seconds. I also tried 2.0 and 1.5.



In the top image, the 1.5 exposure is on the left, in the boom it is on the right. I am not seeing a lot of difference between them - admittedly, my phone camera is not really up to the task. I find that quite surprising, given 2.5 is 67% more than 1.5; that is a big range in a relative sense.

What I do see is some parts not quite right for the 1.5 exposure. In the top image, the model has a circle with a cross in it, and the cross has broken in the 1.5 model. In the bottom image there is a bit top rightish that has not formed properly.

So 1.5 seconds is too short, but it looks like 2.0 seconds is worth trying.


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