Bubbles and layers in teeth print

I work for an orthodontist using Form 2 to print models of teeth. For several months we have been successfully printing models but in the last 3 days all prints have cavities and visible layers on them. As far as I know the resin tank has not been changed in the last three days. One of the staff members tried cleaning the unit yesterday but it make no difference.

The following photos are all identical models.

Previously printed model:

Example 1 of faulty printing today:

Example 2:

Looks like your optics(including the small galvo mirrors) are still not perfectly clean or the laser has been degraded.

It’s best to contact customer support.

Since I posted the initial photos I had a chance to inspect the printer and noticed the resin bath has some flakes and debris in it that has no doubt accumulated over time. This is likely to be the cause of the problems.

I do not use the printer myself and usually only take care of other computing aspects at the business. I guess a possible solution to the problem is empty the resin bath, clean it, and try another print?

Also is it necessary to close the resin tank’s vent between prints?

You should filter the resin in the tank after every bad print.

Today the prints have become dramatically worse. There’s whole chunks of the print missing now.

Fishing all the flakes and debris from the resin has not made a difference. The seller of the printer has been contacted and has offered to send out a new resin tray to try. When it arrives I will test the printer again next week and see if there’s any improvement.

I am an orthodontist using Form 2 to print arches. 1) Your galvo mirrors have to be cleaned. It is a pain, and I use a curved hemostat to hold a cotton swab to reach them. Instructions are available on Formlabs support pages. 2) When you get bad prints you need to filter the resin and clean the tank out. I use a funnel in which I insert a paint filter (for the small stuff) plus a kitchen wire mesh drain basket to catch the big stuff. The big stuff can clog up the paint filter and it will take all day for the resin to pour through the filter. 3. The resin tank bottom can be distorted. This happened to me once.

You need to filter the resin from the tank though a 180grit paint filter. Most DIY store will sell them.