The good thing that's come out of making all those mistakes is that now I know how to fix them and also how to prevent most of them. There's always something that can happen but I can minimize the chances.
So you want to know what the mistakes were? Of course you do.
The first one was not knowing how to get the best settings. There's all kinds of preferred ways. As it turned out the default settings that came with the printer were almost exactly what I needed to use. More on that in a bit.
Once I knew the settings then I had to figure out how best to support the prints. Ya see, these prints need a hella lot of supports. They print upside down so anything that sticks out needs some kind of attachment point. They also work best when parts are vertical rather than horizontal. Here's a visual. Notice the wacky angles of these things. It's a trial and error process really.
See the lattice? That's support material. It narrows to a very fine point where it attaches to the print but it has to adhere to the base. See, there's a battle going on between the resin that's cured on the film at the bottom of the vat and the resin that's cured on the print. The film is supposed to release so that the print builds. Notice those words - "supposed to".
Those supports are nice but they're not enough. The print lost the battle when it came to being pulled up off the film. I did two things to fix that. I added a pad below so that there was a LOT more adhesion to the bed and I slowed down how fast the bed moved up. That way it had time to release the suction. Here's what a print looks like with the pad below the supports.
Yes. Different models. And look at those supports! But that problem resolved itself nicely. From the first picture I put the middle model directly onto the print bed without those supports since she didn't need extras. And I had quite the time prying her off. When they adhere they can really adhere.
What happens when a print fails? The resin builds up on the film below. This is bad since the print bed is going to push down on it for every layer it tries to print. That's why my first film got punctured. And it's why they ship the printer with another film. I've since ordered more, just because I know I'll need them and I won't want to wait or hope they're in stock.
Cleaning cured resin off the printer itself isn't bad. The glass screen is tempered and sealed so resin won't leak into the workings. Soften it with isopropy alcohol on a paper towel and gently scrape it off with a razor blade. Wipe it clean with the alcohol and it's done.
I've had to clean out the vat and remove the failed print a few times now. It's not any big deal once you've done it. Pour out and strain the resin. Pour some isopropyl alcohol into the vat to soften the print (and to check for leaks). Wait. Gently, oh so gently, pry up the cured resin. Check for leaks. Clean thoroughly with isopropyl alcohol. Wipe dry. Replace and refill with resin.
It's pretty much the same process as for when you change resin, except for that part about prying off cured resin.
I've also learned to check how much resin is in the vat before starting a print. While they typically don't take all that much they do need some. I had a print fail because the resin ran out and even though I thought I added more in time I did not.
The only other thing I've done wrong (that I remember) is the orientation of a print when supporting it. This is a big deal. You want the best combination of angle for printing so the details don't get support nubs but the print is going to be firmly attached. The one I messed up had a weak spot where the model itself broke off when the print lifted. Live and learn.
I also learned to check the print about thirty minutes in. Pause it, let it lift to the top, check the print on the bed to make sure that it's adhered and printing properly. Better to catch errors early than to have a big buildup of cured resin that will poke holes in the vat film. All my prints seem to include complimentary cat hair. I guess that's my hallmark now?
Here's a big batch of successful prints. Some of them are for other people and they asked that the miniatures not be attached to bases because they prefer to do that themselves. Fine. That's no problem for me because I need to use a CAD program (Meshmixer) to combine a base with a mini for printing anyway. Most of the ones in the picture were done that way. A few had their bases already in place. Let's just say I've gotten reasonably good at placing mini files on base files and combining them into a single printable file. I'm kind of proud of that.
To be honest this probably one of my least favorite prints. It's from DesktopHero3D which is a site where you can make your own minis. It's a fun site but the problem I've found is that the resulting files are too detailed. It turns out you need to exaggerate the textures and details for them to print well. On the screen that chainmail shirt has wonderful texture. Here? Not so much. But it works and I'll continue to make minis there because it's fun. I added her to a base because DesktopHero3D only has round bases and square ones work better in my games right now.
This guy is the Vampire Lord from Vae Victus (a Patreon) and I really like that swirly cloak. I'm a sucker for fabric. I think he'll be fun to paint.
Notice the difference in details between that one and the one before it. That's the difference between a file designed with detailed options and one that's designed as a unit specifically for printing. Both are good. The Vampire Lord has some thickness to that cloak that's way out of scale. But it also helps keep the mini solid. You can't see it in this picture but he's on a base that was already included with the file.
The picture is a little blurry but this is the chibi version of a couple of 1920s figures from the Gangster Bang Kickstarter. There's full size minis in there as well to match the chibis but I've been wanting to try painting them for a while and now I can print them. These came on their bases so no problems there. Well. Problem. The sculptor didn't do the chibi eye that's most commonly used here. He used a Japanese style that is meant for decals. We had to ask him to make real eyes since he just had an empty space meant for those decals. It was kind of creepy. But he found out more people wanted to paint them than use the stickers so we could choose which option we got.
In that pile above are a bunch of minis from Artisan Guild. They're a very popular company. If you look closely you'll find several of the same orc pinup girl. There's also some laying down that are theirs. The person who wanted those didn't want the bases. The one who bought the orc pinup girl did want her on the base and the way she's designed she's better on it so that her weapon is accurately placed. The ogre is also theirs. You can see him in the properly supported picture along with the other one lying down.
Now that I've got the printer working I've had to learn how to post process these things. It's not like the other printers where it's ready to go once you pull it off the print bed. Sure there's supports to remove but it's not nearly the same.
The resin is caustic so nitrile gloves are a must. I cheat and reuse them a few times but this stuff will eventually degrade the nitrile. Latex is not to be considered except as a very last resort and even then only for short periods of time. Sweaty glove hands are part of the process.
The first step is nipping off all those supports. The outer layer of the mini has a coating of excess resin so it's soft. Removing the supports at this point is best since they're most easily removed.
Then it's time to take a craft knife to shave off support nubs. That means running your fingers over all the parts where they attached to feel if they were left behind. The soft resin means it's really easy to get rid of them. Care must be taken in both steps not to cut off parts of the mini. At this point you've got a smooth mini ready for the next step.
The excess resin on the surface has to be removed. I'm using Simple Green in a 1:1 mix. There's other cleaners out there (Mean Green, etc.) that work just as well if not better. The sites all say to use isopropyl alcohol but tests have shown that's actually the worst performer and if you get it wet before the alcohol evaporates it leaves a white reside. I drop the parts into a container of Simple Green when I scrape them off the bed and put them back as I work through the set.
I was using a toothbrush to clean off the resin. It can work but honestly it's a lot of work and mess for not exactly great results. The sites all talk about ultrasonic cleaners so I finally broke down and got one. Oh. My. Goodness. The difference is incredible. I put the prints into a small ziplock bag with Simple Green, seal it, put it in the cleaner, add water to fill the container, then run it for 280 seconds.
The resulting Simple Green is a sickly opaque yellow green when it's done. And yes, I pour it back into the container. Once it gets too nasty I'll put it in the sun to cure out the resin, strain it, and add fresh cleaner to keep going. I dump the cleaner, rinse the minis, and put them in a small Tupperware for curing. I cure under water for reasons that are scientific and boring.
Fun note. If the figure is multi part you assemble it now. Then when it cures it's one solid piece. It also reduces the potential shrinkage issues that come with resin printing.
The resin cures under UV light - sunlight. So I have a curing station (that's the CAD design I did up there using Tinkercad) that I've lined with tinfoil, is on a tinfoil base, and has a solar powered turntable where the turntable platform is also covered in tinfoil. The intent is to get as much light from as many directions as possible. The lamp itself sits on top in the brackets meant for it. It doesn't fit complete tight so there's space for heat to vent.
Yes. I printed my curing station on one of my other printers. I'll be posting it up for other people to download at some point. The light and turntable were a package deal on Amazon.
I put the Tupperware on the turntable, the lamp on the curing station, then let it bake for about sixteen minutes. After that I can handle the prints with bare hands since they're done. Done!
As you can tell resin printing is a lot more involved than the other kind. But you get incredible detail (I'm at the coarse level of 0.05mm per layer. I'd like to get it to 0.03mm. That's as thin or thinner than a human hair.) and honestly it doesn't take as long as you might think since the entire layer is cured at the same time.
I've got a number of print beds sliced and ready to go. Once I clear the prints off the bed I clean it, replace it, check the resin level (important!), and start the next print. After that I can work on processing the previous prints or let them sit in the Simple Green for a while. It's not going to hurt them. Or I can leave the prints on the bed for a day or three until I'm ready to work on them, as long as they're not in sunlight.
Uncured resin is caustic. That means all those supports that I remove need to be properly cured before they can be thrown away. I have a large plastic bowl in the sink where I keep the majority of the mess and I've cured the supports a couple of times by putting the bowl outside in the sun. Now I have supports cured to the stupid bowl. The next time I'm at the dollar store I'm getting clear plastic cups so I can transfer the uncured slag to those, cure it, and toss the whole shebang.
As I said, live and learn. And print!
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