Noir Printing Issues for Siraya Fixed with Light Delay

We purchased the Noir to augment the printers we already have in our small business (IE not new to this type of printing, just new to Noir) and we have had a myriad of problems with prints failing when using Siraya FAST and Blu.

Generally we are printing solid objects with X*Y dims bellow 100mmX100mm and some examples of what we have seen are:

  1. Thick half cured resin around the first cm of the print that is impacting finished quality.
  2. Large partial layer delamination where it looks like 1/3 to 1/2 the print just started peeling back, actually looks like what you see with FDM printing ABS if you dont have a heated chamber its so bad.
  3. Prints being angled for the first cm or two if they are not printed right in the center of the screen.
  4. FEP getting worn out very quickly and dead areas showing up on the LCD.

This is specific to solid object printing and the issue will be masked if you hollow your prints or are printing smaller objects though not entirely erased and may not show up using the deft resin which we are currently unable to get due to back order here.

What appears to be going on is that the Noir is simply…too powerful. When the build plate drops the print down for the next layer it drives to what it believes is 50um above the last layer but the moment when it stops it will actually be 53um/54um/55um, something larger than the expected 50um because the resin needs time to escape from between the FEP/LCD and the print. With other printers running long cure times the resin has a while to get out of the way before the light can jell it. But on the Noir it just gets flashed in place adding an extra um or two because the curing light is…really strong. Repeat this for a few hundred layers and it builds up enough that you can watch the whole build plate being flexed up each time the print touches down and you start getting crazy print failures and the print putting enough pressure on the screen to cause damage. I wanted to think that this couldn’t possibly be the problem because after the first few layers you should hit an equilibrium where the print is a bit too long so it presses down a bit harder so it pushes more resin out of the way and then you start hitting the right layer height…But I added in a light off delay in chitubox that put a little time between when the plate stops driving down and when the light comes on and now the printer runs beautifully. Tested with a 100mmX100m block print and put it way off center (which should have been the worst case scenario) and there are no issues with it so I’m feeling 90% sure of all this but if anyone else has input I would be interested to hear it.

Photo for example of the kind of crazy stuff we were seeing until we added a light off delay.