Test Project 2: Troll

Projects & Prints
1

Had a bit more luck with this model.

This is a stock model as well - decided to print ‘as is’ as the geometry was pretty good. Only a few open holes and Preform seemed to clean them up ok. Otherwise the skin was a continuous mesh - which was a huge win.

I was worried about thickness, so I scaled down in Preform to keep it under 8cm… so the midsection was not too thick.

My impression is that printing anything too thick causes problems, and I think this was probably right at the limit as I saw a bit of bubbling at the thickest part of the print (maybe 2cm?).

I mounted him manually, tipped back to minimize support marks on the front side. I basically jumped back and forth between support editing mode and the slicer view/main so that I could place supports exactly under any "island’ in the slice plane that was not supported. Maybe 30-45 mins of effort. (Side note - I really wish there was a way to scale a FINISHED preform model, including supports so I could test out various print sizes! Not being able to do so makes it very tempting to just model supports outside of preform, which would be a bummer - will add a wish for this).

Definitely this feels like a sweet spot for the Form1 in terms of characters… much bigger and you have to start hollowing out for sure (though I’d still like to find an efficient way to do that… I’ve not found a lot of great options in existing tools, though the z-brush tutorial referenced elsewhere on this site is a great option if that is your tool of choice.

I had no issues with platform attachment. Still seems pretty snug after 3-5 prints. I have taken to using a razor blade exclusively to get stuff off. Its a bit dicey with gloves on and resin everywhere, but it seems like the only way to get the print off without the risk of stuff breaking and flying around. I’m actually thinking of putting the platform in a vice instead of the Formlabs tray so I do not have to hold it down while trying to get the print off.

Perhaps worth noting the the smoothing of the poly goemetry (120K tris) was not great… I ran it through a smoothing filter in meshlab just to flatten stuff a bit… but it was still not great. I was surprised to see how relatively smooth things ended up. on the body. The teeth however maintained high detail and the printer delivered nicely (though I had some trouble getting a good camera shot to show that off).

BTW - he used about 50ML of grey resin. (I have black on order and will be interested to compare).

Here are some pics (again, this is not my model - just trying to see what the printer can do).

Fresh from the printer… still slimy

Probably could have used less supports, but I was playing it a bit safe. Might try again with less.

There is an interesting line at mid-shoulder all across the chest and opposite arm. As if the printer was paused, but I did not do that. It is subtle, but curious. I wonder what happened there.

Teeth came out pretty good.

Free at Last!

2

Cool print. The prints do look pretty “scary” when they come out of the printed as if there is no detail in them at all.

I have taken to using a razor blade exclusively to get stuff off. Its a bit dicey with gloves on and resin everywhere, but it seems like the only way to get the print off without the risk of stuff breaking and flying around. I’m actually thinking of putting the platform in a vice instead of the Formlabs tray so I do not have to hold it down while trying to get the print off.

You know, I did a test print last night; it was my first with a model I built, something much simpler than your troll.
I did too have a hard time getting the model free from the platform. There are supposedly a “quick release” ? not sure what or where it is.

I also had to use some clamps to hold the kit table to my bench. A vise is a great idea.

3

Thanks Cesar.

The quick release was a mystery to me too, but I finally figured it out…

when you let Preform generate supports for you, one or more of the supports seems to have an ‘under lip’ that gives you room to get a scraper or blade in there.

Unfortunately, when you manually create supports one by one, this does not seem to happen. I would be great if you could check a box when creating any support to request that its base had that lip. Don’t think that is possible to control in any way right now.

BTW, I’m on the hunt for a huge razor blade with a safe handle. Might sharpen a super thin paint scraper, but I am a bit worried scratching the platform. Definitely need something safer than the razor.

Jeff

4

Hi Jeff,

First off, the troll looks amazing! Good Job!

From reading your post you seem to have a very good sense of how to properly orient and support large models. Working at Formlabs and printing large items(especially characters) on a frequent basis I’d like to clarify a few points and make a couple suggestions.

I am a huge fan of using the ‘generate selected’ option in support structures and then using the ‘edit selected’ option to modify supports as I see fit. One of the first things I do for large items is make sure the touch point size is between .4 and .6mm. During the peel, large solid objects will exert move force so you need the slightly large touch points to hold the object. This also allows you to turn down the density on the slider a little bit. If you still feel that there are too many supports, you can always increase the flat spacing in the advanced support menu. After generating supports I’ll go through the object with the slicer and use the ‘edit support’ feature to reinforce or remove supports. This should help you cut down on the time it takes to support your prints.

One of the things we do excel at is detail which makes the printer great for character designers. However, you are right about having to hollow out large prints. I have successfully printed some very large(near full build height) solid creatures, but there is a greater chance of failure and it requires a lot of resin. In terms of programs that help with hollowing, a number of people around the office use MeshMixer to great success(also a free program!).

Black has actually been formulated to provide higher detail so your characters will look even sharper!

Once again, good job. Your Troll is really really cool!

Cheers,
-Clark

1 Like
5

Why black and not a lighter color? I ask because black is hard to cover when painting.
Also @Clark_Anthony, while this is not my thread, I appreciate your post and insight.

Yes it seems the form 1 is great for figures, this should make it great for architecture - ?? Has anyone at your office some any architectural prints to scale. ( I am trying to come up with a proper workflow) - mostly scaling to a proper scale without having to go to netfab.

6

Hi Cesar,

Due to the formulation of black, it has a lower penetrating depth for the laser. Because of this, it requires a high laser power/longer cure time but allows for much greater control, hence the better details.

I’ve seen a few architectural models printed. I can certainly ask around and see if I can find some files/models. Let me know if you have any other questions!

7

Thanks very much Anthony.

I am still learning - no question.

I will go back and give generate selected another close look. I may do some comparison prints between manual and auto just to get a sense of whether i am wasting time doing this stuff manually. My initial thoughts are that for longer prints (7+ hours) if manual set up is less than 1 hour, it is kinda worth my time, esp as I get a better feel for what works and what does not. That said, given the peeling insights you mentioned, I have renewed concern that maybe I am going too light with supports and might be on the thresh hold of more failures. Either way, I’ll dive back in and give that a try. Thanks again for the tips. More tests to follow.

8

I would like to see some example or architectural models.