Testfile didn't print succesfully - Base plate too thin


For about two weeks now I wasn’t able to print only one succesful part. I’m continously getting the same errors.

When I set the base plate thickness to 2mm in PreForm the printed result only measures about .6mm. That is far too little I think. Even when I set the thickness to 4mm the result is only about 1.6mm.

I used the standard testfile with the 5 butterflies at 100 micron with clear resin.

The overall result of the print is also pretty bad as you can see in one of the attached pictures. The butterfly in the middle didn’t adhere to the build paltform at all. The other four butterflies seem to be not cured properly, they’re very wiggly and not as strong as normally. Small details aren’t printed propely, too.

It doesn’t matter how often I try to print the tesfile. The results are all pretty similar.

Things I already tried together with formlabs support:

  • Setting an offset on the Z-Axis (Height of the build platform above the resin tank) (.2 and .5mm higher than ususal) to reduce compression

  • Setting the type of resin to grey in PreForm to increase the exposure time

  • Cleaning the inside mirror, the build platform and the resin tank very well

  • Using fresh resin from a new bottle

  • Laserspot test (small round spot as expected)

  • The resin tank looks good in general (some small signs of usage I think, no clouding, only three small imprints of older cured resin I removed outside the area where the testprint takes place and a slight scratch from the scarper)

The printed results weren’t better than before. I attched pictures of the first result without modifications and also the best result, when I set the base plate thickness to 4mm together with an Z-Axis offset of -.5mm (higher).

Is there anyone having an idea what might be wrong with my printer, because I haven’t received an answer from the support yet (for about 6 days now) and I need to print some smaller and bigger parts until January 24 if possible.

Thank you in advance!

I would send them another note on the ticket.

Is the PDMS layer at the lower line of the min/max fill line? From what I can see in the picture, it looks ok.  Did you try using a second vat and build platform?  When you installed PreForm did you select the "send data to Formlabs?  If yes, they should be able to “see” the laser output performance (I believe) did they say anything about this?  From where I am sitting, your printer has 2 separate problems but they may be related somehow.

  1. Z height issues.

  2. Print quality issues.

I am surprised they did not respond for 6 days.  Something does not sound right.  Is it possible the email got flagged as spam?  I am assuming you looked up the support ticket on this site.  There was a time I missed the email and found they were waiting for me to respond.  Just a thought.

Good luck and let us know how you make out.


Yes, I looked up the status of my request online. And I already added three more notes on the ticket because I made some more testprints with different settings and reported the results.

Concerning your second question I can say that the PDMS layer is on the same level as the lower fill line, although it’s hard to see.

Tuesday I’m going to receive a new tank to find out if my resin tank is faulty. But I’m not very confident that this will change the results, because I always handled my vat with a lot of care and two weeks ago everything worked perfect. But of course it’s worth a try!

Thanks for your answer!


Did they send out the resin vat or did you order it?  Did the original vat ever work correctly?

No I ordered the new vat on my own to save time. But I just asked for a refund in my latest comment in the current request because my vat has only been used with half a bottle of resin till now. Not much to my mind.

And yes, the original vat worked (of course with some failed prints) as recently as about two or three weeks ago.

The only bigger issue I had before was that my printer’s peel motor screw has detached from the clevis under the socket of the vat so that the resin tank didn’t come up again but I was able to repair it with he help of the support team. In this case the support was excellent quite contrary to my current request.

I hope the’re going to answer tomorrow.

Strange, not like FL.  I am sure it is just an oversight.  Hopefully they will address your issues tomorrow.


I am very sorry that you have waited so long for a response. For some reason your request was not being sorted properly in our queue. I am reviewing your message now and will respond shortly.

I promise we will get you all sorted out today.


Hi Leon,

The Form1 resin tank is mounted on tensioned springs - it sounds to me like the tension on your springs is a bit loose - hence letting the springs hold the resin tank higher than is optimal for printing with bases at 2mm or less. You can increase the tension by tightening the nuts shown in the attached pictures - this will lower your resin tank slightly so that the initial platform layers are printed without the tank being pressed up hard against the build platform - you will then get better bases.

I had the same problem with my current printer - 2mm bases were printed at about 0.4mm thick - tightening all 4 nuts nuts a 3/4 turn now gives me 0.8mm bases. I need to tighten them some more, but you have to unscrew and remove the top aluminium and cover unit, as well as the front and back plates to get at the nuts, and it’s printing ok at the moment - so I’ll get round to it at some point.

See attached picture taken looking at the right hand side of the Form1 with aluminum_cover unit and back plate removed. Front plate is still attached this needs to be removed to get at the nut circled second from left - that’s actually behind a bit of Form1 frame.



I got an answer from Formlabs as promised by Jory. They said that I should try out the new vat which is arriving tomorrow and if this won’t work I’ll get a replacement machine immediately. That’s the kind of support I’m used to receive from FL, excellent.

I’ll also take a look at the adjustement nuts mentioned by Kevin.


Just for any wanderers through this thread, I wanted to mention that you should not adjust the tension nuts on the peel platform depicted in the photo above. Even if there is a tilt, the platform has been carefully calibrated to each machine and adjusting tension will throw the machine out of calibration and void your warranty.

As stated previously in this thread, if you are having issues with your machine, please message us at support@formlabs.com and we will take care of you.


@Jory - and the rest of Formlabs support.


For adjusting their machine in a way which can do no lasting damage (the worst that can happen is failed prints) and which is entirely and easily reversible - for that; you are going void their warranty - this from the folks who have been promising to do all they can to keep us happy.

Have you and Sam actually got elbows deep in a Form1? stripped it down and put it back together? if not I think you should, it would give you some very valuable perspective before threatening voided warranties over adjustments that are simple, can do no lasting harm even if they are done incorrectly - and which are easily reversible by someone who knows what they are doing. On top of that, this is perhaps the easiest issue to diagnose on the Form1 - there is no mistaking the symptoms.

In short - it’s a free-shot - their machine is wrong, it’s blatantly obvious when the springs are the issue, it’s very simple to fix, and there’s no risk in the fix. If they get it wrong, your guys can easily undo what they’ve done wrong - doing what you would have done anyway had the customer just sent it in directly. And yet you’re coming on with “void your warranty”.

When I was first told that tuning my galvos for better accuracy would void my warranty, I didn’t like it, but whatever - fine. I don’t know much about galvos, maybe it is possible to damage the machine through ignorantly messing with galvo tuning, that still seems unlikely to me - and my efforts worked out, but I wasn’t about to campaign for you to allow folks to tune their own galvos. I simply detailed my experience and said use at your own risk.

But this - this is unfair to your customers - worse, it’s counter-productive - for you and them. But the crowning glory, the part that really, really burns my wick - is that your service team couldn’t even get this very same simple calibration right on my “factory tested” replacement machine, and yet you’re telling customers “don’t touch this, leave it to the experts, or else!”

My replacement machine - ObtainableLamb arrived with incorrectly “calibrated” (such a grand word for something so trivial) resin tank frame springs. This is a machine that was a replacement - one which I was told would be “factory tested” to make sure everything was 100% before sending it out. Worse it also came with a wobbly build platform. Two issues that are trivial to spot; they don’t even require a test print, and which to me are unforgivable failures to leave a refurbishment/service team.

Have a look at the pics - the first is a handful of the calibration 80mm prints I was running while tuning my X-galvo, notice all the bases were too thin to be removed without splintering - about 0.4 - 0.5mm in fact, when they were specified at 2mm. It was ok for printing such tiny parts though (only a couple of mls in volume) - so I left fixing it until after I’d tuned the galvo. **Nota Bene: **this was out of the box, initially my only focus was accuracy, I hadn’t touched anything except the X-axis galvo trimpot when printing these.

ObtainableLamb is busy printing at the moment, but soon as it’s free, and I have a couple of hours, I’ll put a detailed post explaining how to confirm your resin tanks springs are incorrectly tensioned - and how to fix it. Before the end of the weekend.

Hopefully Jory et el will see reason, otherwise - I’m going to have to go seek anger management counselling for rage-heart-burn.



I got a replacement machine from Formlabs. The outer appearance is very good but nevertheless I’m still having a problem. Every print showed a failure (a slot) in parallel to the peel axis as you can see in the pictures which is leading to further failues in the printed part of course.

The slot I’m getting is always 4-5cm away from the right side of the buid platform. In contrast to this parts printed on the left side (hinge side) came out fine.

I already tried to print an own part and the butterflyclip-file with two different resin tanks.

Any ideas what might causes this? I already cleaned the build platform but it hasn’t changed anything. Is it possible that this failure is related to the current firmware update?



Hi Leon,

That’s terrible and my sympathies. I would suggest checking Both mirrors - presumably you’ve already checked the large mirror, but there is a mirror between that one and the galvos, at the base of the Z-axis column.

You can look at this smaller first mirror indirectly through the large mirror of course, but to get a close up (albeit sharply angled) view, you can remove the back cover by removing the two hex screws on either side of the cover hinge, and the two black middle hex screws at the rear of the sides of the Form1 (be very careful with these, they have a tendency to stick and it’s easy to round out the head, so when replacing them, only do them up finger tight).

Hopefully it’s just a piece of easily removable material on the mirror. Note, you have to be very careful with these mirrors, since laser mirrors are “front surface” mirrors, which means the fragile very scratchable reflective layer is on top of the glass, not behind it.

Hope that helps …


Leon - the more I think about that, the more it looks like a resin on the large mirror - if it is, then I doubt it’ll be possible to remove without damaging the mirror, since it will be thoroughly cured by now.

If Formlabs will accept another return all well and good, but all is not lost if not - replacement laser mirrors are not that hard to find, and the main mirror can be removed (I have done it) it’s annoyingly fiddly, but easy with patience. See the wiki http://form1printer.pbworks.com/ for a source of an replacement mirror I found here in the UK - I’ve actually used it too.

Also - as promised, regarding the OP topic - see this new thread for explaning how to adjust your resin tank level - https://support.formlabs.com/entries/40356477-Adjusting-resin-tank-level-to-fix-thin-bases-and-other-issues-I-break-my-Form1-and-fix-it-in-video-t