My First Print (with issues & lessons)

Hi Folks,

I attempted my first print with the Form1+ and I’ll say right away that I was over-reaching in terms of geometric integrity and technique. But I wanted to see where the baseline was and so this proved helpful, but still is probably beyond me at this time.

The model is a stock “mech” robot - some topology issues - mostly things that get fixed on load. But also some pretty tricky support situations that don’t appear to get caught with the auto-support generation. In the end, I built all of my own stuff manually in Preform, but knew things would probably fail given the tenuous connectivity between some parts supports.


But maybe this is interesting regardless, and you may have suggestions for me to, which I’d be grateful for!

First apparent lesson: I built structures so that there was virtually no “red shading” on any parts of the model. I realized that is probably not sufficient, because numerous areas of the internal structure were not supported “from below” when they started printing. These must have fallen into the resin in small bits until the layer reached a point where I had sufficient support. In my defense, though I now realize I need to walk through the slicer with extreme focus to watch for these “islands” of non-support’… it was otherwise quite hard to see inside the model to place these supports where needed, when in manual editing mode. I’ve put in a wish, but it seems like the best of both worlds would be to be able to see the slicer while placing supports. Not a slam dunk I know, but a wish anyway.

(note that the print failed just above the mech leg’s wall. The supports continue upwards beyond the failure)

Second lesson?: The mech print had weird issues mis-shaping near the base, but not elsewhere. I did a separate ‘known good’ test print with a similar wide base, and both prints exhibited odd bubbling or badly shapped forms in highly dense, solid areas near the base. Those specific anomalies SEEM similar in both attempts (using different models). Both areas were flat and solid and would have pooled resin above in the regions around the base supports as the platform was gradually lifted up. Maybe the density, or the heat, or the quantity of resin pooling, or something else may have been the culprit? But after the printing gets beyond the very dense layer, things seem to get much better. Side note: when I was removing the base support from the bottom of the mech’s foot, the support point pull out of the resin as if it was not fully cured. This was after letting it sit in the sun for 30+ minutes. So it seemed again like that massive solid section was perhaps too much for the curing that happens in the tank? Crazy guess.

Third lesson (aka bone headed mistake?): Could not get back to the printer right away once it finished. It unfortunately had to sit finished at the raised platform position (solidly attached to the platform), all night and partway into the next morning. Maybe 14 hours. Dumb move I know. But being the rookie I did not plan ahead and figure when I really should have started the print so that I could be there when it stopped. I ASSUME that having the print hang there esp with pooled resin (?) is bad? Not sure, but it seems like something I should have avoided… please let me know if you know otherwise or can confirm how bad that really is.

(holes in feet are from where I was able to twist or pull out the supports after curing in the sun for 30 mins - though the base did occlude this section until it was off. Still the resin seemed a bit soft)

Fourth Lesson (a good one - thanks Josh!): Don’t be a afraid to fail. I was and am worried about wasting resin and about the compounded effects of one bad print on the next one (cleaning out failed parts, etc). But I feel like just diving in with a potentially insane part was at least a good learning experience and hopefully will help me hone my technique.

(any idea what the white stuff is in the cracks? )

BIG QUESTION: It is purely a hunch, but I’ve seen a lot of folks putting their prints at an angle, even though it might seem pretty straight forward just stand them up (think of a chess piece for example… seems it should go flat on its base)… BUT, if this pooling thing really is an issue, I can see why an off-angle mount is perhaps better because less resin gets trapped. I also wonder if the big beefy solid base is another problem to be avoided - and hollowing things out maybe helps the printer avoid over-heating the resin? bubbles? no clue. Pure myth and guessing. But looking at two prints so far on a new printer, I perceive similar issues.

NEXT UP: I’m going to try to test a model with clean geometry, but which is otherwise fairly sparse and open, though well-supported. The parts in my first Mech print that seemed to come out the best (and maybe show off the Form1+ the best?) seem to be relatively thin area with well-supported structures, not the chunky stuff. The hunt is on.

Thanks for any observations or advice you may have.


PS I created manual supports using 0.2 mm setting. These seemed to do a great job supporting things and came of quick and clean. I only spent about 40 mins on the stuff you see here above. But maybe the upper part of the leg would not have failed if I had gone bigger? Not sure.

Well, rest assured, letting your print hang afterwards doesn’t hurt the print – in fact it is recommended by Formlabs to let it stay there for as long as possible to get the residual coating of resin off the part (which helps in post-processing of the print)

To me, it just looks like it was just too thin, but I wouldn’t say that’s the root cause.

Also, in general, you need to avoid horizontal flat surfaces as much as possible (bottom of the mech foot). Ideally, you’d print it at 45 degrees, but I’m thinking it wouldn’t fit if you oriented it like that.

Thanks David. That’s a pleasant surprise. I’ve followed that practice on the next two.

I tried something a bit more manageable for the next print - these are the guns from the same mech. Nothing too fat, through a few thin areas that did not print (my fault really - they were super thin).

I did left and right guns in the same print - one oriented vertically and one at a 45deg angle. I think I like the angled one better - but mostly because it was easier to clean. They both were about as good in terms of print quality as far as I could see.

Here are a few pics of the guns. They are each about 8 cms long.

and an upper-arm section…