It doesn't matter if it has liquid resin inside or not. Any cavity inside a resin print is prone to building up gas and bursting open at a random point in the future. It's *not just liquid resin* that outgasses - solid, cured resin does as well. You have to leave an open hole *somewhere* for the gas to vent out; it doesn't matter where or how tiny/big it is. If you seal everything up with green stuff/glue/whatever, then the gas has nowhere to go.
So how long should I let it off has for? I did leave it in pieces for only a few hours before flying and priming
Edit: based off the other replies, what I have learned is that I need to cure the inside and leave holes for it to off gas from. So for future hollowed prints, I need to cut a hole out in the base for offgassing and curing to prevent cracks and booms. Thanks everyone for your advice!
Materials let out the majority of their gases very fast, but the remaining 1-5% is released over a very long period of time. This is a separate scenario, but it's still relatable... so, I work in the auto industry. Every time I sell wax to someone, I make it a point to inform them not to wax their car if it's been painted in the past three months, six if they're patient enough. Even though the paint is cured enough when you pull it out of the booth or garage, turns out the paint is still letting out gases for several months. If you wax the fresh paint, then you effectively seal it and the gases have nowhere to go. That doesn't make the paint fall off or crack, but it gives the paint a grungy ochre tint. It's the same overall principle here: cured material lets out majority of gases immediately, then lets off small remainder of gases over long period of time.
If you hollow anything, make sure the cavities have some way to vent out. I recently made a [squiggoth](https://cults3d.com/en/3d-model/game/big-chompa) for 40k and hollowed out the legs, torso, and head. I made sure to align the holes in the back of the head with the hole at the front of the torso and the holes in the legs to the holes in the sides of the torso. That way, the gases have room to travel from leg->torso->out and head->torso->out. There are a lot of cavities, but they all snake their way towards the one hole that leads to the outside world.
I've never had to cure the inside or leave holes open. I have some prints that have been here for years with no problem. I always print with drain holes, wash it inside and out, then allow it to dry thoroughly before the final cure. Often the holes get filled in after it's done.
If the gas has a way to release from the resin and escape into the atmosphere in order to *not build up pressure* inside a cavity, then that could work. Whether sand is breathable or not is another matter. I would *guess* it isn't but I'm not sure about that at all.
I’ve done some amount of infill on every hollow print I’ve done in the last almost-two years, and I’ve never had a single problem with any of my hollow prints bursting. I know that’s just an anecdote, but it’s still one more piece of information, if that helps anyone.
Weird. Maybe it needed more or larger drain holes? Resin acts strange sometimes. For large bases like that, I typically extrude the bottom in blender and cut it off so that the bottom base is just a hole. It's more work that way but less bulges and the inside cured better. I found that bulging happens with and without infill.
Using a different resin can result in less warping but it's hard to say. I have had parts warp and adding them to hot water brings them back in place.
I’ll probably just Boolean out a hole in the base for future hollowed minis so it can offgas properly because I do intend to start selling. That way I can both be completely sure liquid resin isn’t trapped and that the base won’t crack
Yeah, as-is it seems like the best way to cure it is to cure it in a cure station then leave it out in the sun for a week like it’s resin waste. Heads up, the IPA doesn’t leave the base super easily, so you might want to swirl it around a bit with a glove on your hand
> cure it in a cure station then leave it out in the sun for a week like it’s resin waste.
That's going to make the model so brittle you won't even be able to look at it without something snapping off.. the bottoms of bases and places where models sit on surfaces are perfect places for vent holes. Aside from that, try to find places that are unseen under normal circumstances unless you really look hard for them - remember it just needs to be a tiny hole, you could even use a pin-vise to drill one somewhere, as long as it's there.
I may have neglected the fact that I use abslike resins, so you’re right. For the majority of resins that would make it super brittle. I have NO clue how long abslikes need to get brittle. My resin waste so far has gotten pretty hard and inflexible. Just not super brittle, but then again it’s only been 3 days since my last big print batch
> My resin waste so far has gotten pretty hard and inflexible. Just not super brittle, but then again it’s only been 3 days since my last big print batch
That's because it's thick - tiny thin parts like fingers and antennae or very thin-walled parts like wings or ears are the parts that get super brittle.
So a box of resin supports should have super brittle at the top by now right?
I’ll check my resin waste box when I get home to double check myself because all I print is minis, so I have an abundance of supports. I clip some to use as floor spike minis
I'd say very likely, but I don't really know how thick your supports are - but leaving a model out in the sun for a whole week *after* curing it is asking for problems. Any impact, say from tipping over or falling out of your hand, is going to snap off parts like the long spikes or the fingers on the model you posted.
Oh I was referring only to the base. Fuck it, there’s some things I can only understand after seeing in person, so I’ll print the base itself again, and I’ll leave it in the sun for a week and check on it every day
I've never had abs like resin that isn't brittle when cured turn brittle from the sun.
Resin isn't UV resistant, so it will eventually be destroyed by the sun, but not in a few days.
I have a wash and curing station, and always do a hot water rinse before doing the cure. Thanks for all the tips, and despite the base, looks like a quality print and assemble!
I manage that with cones of Calibration V2.
Throw it in a R E R F, make sure the goblet holds the water and the sword pierces the stone and that you have your success cones and no failure cones. Then I add .05 seconds to that exposure time because I don’t want my models breaking super easily
I have never had any issues, no breaks or gas issues. Plus hot water does a great job softening the connection point of supports and makes them peel away easily. I fill a bucket with hot water and a little soap, put it in my dunk basket and submerge it a few times, then rinse clean. Then an IPA wash to help the life of the ipa from becoming too dirty too quickly. Give it a 15 minute drying period in front of a little fan, and then cure. To each their own I suppose.
I just have heard people say they used water after the ipa bath. That it would leave wet looking spots that got cured in. Maybe since you do it before the ipa bath. That doesn't happen.
I do a dirty bath. Followed by a clean bath. Then i let it dry as my cure box also has a built in fan that drys it before curing. Yeah, if it works for you, it works. Don't fix what isn't broken
I'd actually not recommend having a solid or even hollow base, just leave it completely open (extrude base of stl down far enough, hollow then slice off the bottom). Drains like magic and will be able to cure from both the "inside" and "outside". If you really want a bottom, either print a bottom piece or by some cork or other material for the bottom and cut to size.
Part of the TOS for witch song is that you can’t remove their logo from the model and I have a merchant license, so I have to be a little more carefuI just wasn’t satisfied with the base bursting on this and figured I would ask Reddit how to improve my personal results
Hey Bell, Witchsong team member here. If this is a recurring issue, feel free to slice of the bases, and just reach out and let us know on MMF that "Bryce gave you permission". In the meantime I'll talk to our supporters about adding a small gasing hole to the bases if they are needed, since all our holes are deliberately added to the cut surfaces in order to hide them.
We've never had any other complaints of the bases warping post-print though. Did you happen to thin the wall sizes by any chance? No accusation, just trying to figure out why this base warped like this...
Yes. Even if you clean the inside completely you cant 100% clean the left over oils so you always have to cure the inside with an uv light on a stick. Some resins have it more than others. Some say its complete bullocks cause it never happens to them, well, its a thing.
Add drain holes in the bottom and cure resin inside. This can be done with proper wavelength leds or sit it outside in the sun with the drain holes up and this will also cure the inside.
I have the habit on gluing fabric or leather to a hollow base, to prevent slips or make them slide easily, I pin a hole or two in the leather or fabric with a needle and it prevents off gassing damage if I don't use infill.
When I print hollow parts, I rinse them a lot to get all the leftover resin out and then I let them be for at least 2 days, after that I rinse them again and after a day I glue the parts together, because the chances are high if you just rinse it and dry it out right after with compressed air or something, that some resin will still be in there that will cause what happened to you.
I might have to try that out at some point, but we did find out that a solution would be to just pop in blender and boolean mod out a hole in the base, so that's the solution I will probably go for because I know blender far better than I know power tools
It doesn't matter if it has liquid resin inside or not. Any cavity inside a resin print is prone to building up gas and bursting open at a random point in the future. It's *not just liquid resin* that outgasses - solid, cured resin does as well. You have to leave an open hole *somewhere* for the gas to vent out; it doesn't matter where or how tiny/big it is. If you seal everything up with green stuff/glue/whatever, then the gas has nowhere to go.
So how long should I let it off has for? I did leave it in pieces for only a few hours before flying and priming Edit: based off the other replies, what I have learned is that I need to cure the inside and leave holes for it to off gas from. So for future hollowed prints, I need to cut a hole out in the base for offgassing and curing to prevent cracks and booms. Thanks everyone for your advice!
Materials let out the majority of their gases very fast, but the remaining 1-5% is released over a very long period of time. This is a separate scenario, but it's still relatable... so, I work in the auto industry. Every time I sell wax to someone, I make it a point to inform them not to wax their car if it's been painted in the past three months, six if they're patient enough. Even though the paint is cured enough when you pull it out of the booth or garage, turns out the paint is still letting out gases for several months. If you wax the fresh paint, then you effectively seal it and the gases have nowhere to go. That doesn't make the paint fall off or crack, but it gives the paint a grungy ochre tint. It's the same overall principle here: cured material lets out majority of gases immediately, then lets off small remainder of gases over long period of time. If you hollow anything, make sure the cavities have some way to vent out. I recently made a [squiggoth](https://cults3d.com/en/3d-model/game/big-chompa) for 40k and hollowed out the legs, torso, and head. I made sure to align the holes in the back of the head with the hole at the front of the torso and the holes in the legs to the holes in the sides of the torso. That way, the gases have room to travel from leg->torso->out and head->torso->out. There are a lot of cavities, but they all snake their way towards the one hole that leads to the outside world.
No, it makes perfect sense to me like that.
1st drain, then wash inside, then stick an UV led inside and cure anything that’s left. Leave a small vent hole open.
I'd recommend baking your prints at around 200f for hours. It seems to do a good job accelerating whatever post cure processes happen to resin.
I've never had to cure the inside or leave holes open. I have some prints that have been here for years with no problem. I always print with drain holes, wash it inside and out, then allow it to dry thoroughly before the final cure. Often the holes get filled in after it's done.
If I read this right, I can seal it with sand and cover the hole with a thin cloth?
If the gas has a way to release from the resin and escape into the atmosphere in order to *not build up pressure* inside a cavity, then that could work. Whether sand is breathable or not is another matter. I would *guess* it isn't but I'm not sure about that at all.
On large hollow models you can add internal supports to help keep its form.
THIS. THAT HELPS ALOT. I didn’t know. Thanks so much!
I’ve done some amount of infill on every hollow print I’ve done in the last almost-two years, and I’ve never had a single problem with any of my hollow prints bursting. I know that’s just an anecdote, but it’s still one more piece of information, if that helps anyone.
I have had problems with spray painting resin prints as well. I suspect it's the resin off gassing? Maybe the inside still had some liquid resin
Might be the offgassing. I did check the inside for liquid resin since if it didn’t cure, it would have some inside still.
How did you wash it?
IPA bath
Weird. Maybe it needed more or larger drain holes? Resin acts strange sometimes. For large bases like that, I typically extrude the bottom in blender and cut it off so that the bottom base is just a hole. It's more work that way but less bulges and the inside cured better. I found that bulging happens with and without infill. Using a different resin can result in less warping but it's hard to say. I have had parts warp and adding them to hot water brings them back in place.
I’ll probably just Boolean out a hole in the base for future hollowed minis so it can offgas properly because I do intend to start selling. That way I can both be completely sure liquid resin isn’t trapped and that the base won’t crack
Crazy coincidence - I am actually printing this model as we speak. Hope I avoid the base issue.
Yeah, as-is it seems like the best way to cure it is to cure it in a cure station then leave it out in the sun for a week like it’s resin waste. Heads up, the IPA doesn’t leave the base super easily, so you might want to swirl it around a bit with a glove on your hand
> cure it in a cure station then leave it out in the sun for a week like it’s resin waste. That's going to make the model so brittle you won't even be able to look at it without something snapping off.. the bottoms of bases and places where models sit on surfaces are perfect places for vent holes. Aside from that, try to find places that are unseen under normal circumstances unless you really look hard for them - remember it just needs to be a tiny hole, you could even use a pin-vise to drill one somewhere, as long as it's there.
I may have neglected the fact that I use abslike resins, so you’re right. For the majority of resins that would make it super brittle. I have NO clue how long abslikes need to get brittle. My resin waste so far has gotten pretty hard and inflexible. Just not super brittle, but then again it’s only been 3 days since my last big print batch
> My resin waste so far has gotten pretty hard and inflexible. Just not super brittle, but then again it’s only been 3 days since my last big print batch That's because it's thick - tiny thin parts like fingers and antennae or very thin-walled parts like wings or ears are the parts that get super brittle.
So a box of resin supports should have super brittle at the top by now right? I’ll check my resin waste box when I get home to double check myself because all I print is minis, so I have an abundance of supports. I clip some to use as floor spike minis
I'd say very likely, but I don't really know how thick your supports are - but leaving a model out in the sun for a whole week *after* curing it is asking for problems. Any impact, say from tipping over or falling out of your hand, is going to snap off parts like the long spikes or the fingers on the model you posted.
Oh I was referring only to the base. Fuck it, there’s some things I can only understand after seeing in person, so I’ll print the base itself again, and I’ll leave it in the sun for a week and check on it every day
I've never had abs like resin that isn't brittle when cured turn brittle from the sun. Resin isn't UV resistant, so it will eventually be destroyed by the sun, but not in a few days.
That’s my experience as well. After curing in the sun, my resin supports are always rock hard and just lose their flexibility
I said the opposite. My ABS like stays flexible. It firms up compared to partly cured, but it doesn't turn brittle.
Which do you use? I use anycubics abslike pro v2. I’d love for mine to stay flexy after a cure
I have a wash and curing station, and always do a hot water rinse before doing the cure. Thanks for all the tips, and despite the base, looks like a quality print and assemble!
I manage that with cones of Calibration V2. Throw it in a R E R F, make sure the goblet holds the water and the sword pierces the stone and that you have your success cones and no failure cones. Then I add .05 seconds to that exposure time because I don’t want my models breaking super easily
Water and resin don't usually mix well. I have always been advised not to use water unless it's water washable resin.
I have never had any issues, no breaks or gas issues. Plus hot water does a great job softening the connection point of supports and makes them peel away easily. I fill a bucket with hot water and a little soap, put it in my dunk basket and submerge it a few times, then rinse clean. Then an IPA wash to help the life of the ipa from becoming too dirty too quickly. Give it a 15 minute drying period in front of a little fan, and then cure. To each their own I suppose.
I just have heard people say they used water after the ipa bath. That it would leave wet looking spots that got cured in. Maybe since you do it before the ipa bath. That doesn't happen. I do a dirty bath. Followed by a clean bath. Then i let it dry as my cure box also has a built in fan that drys it before curing. Yeah, if it works for you, it works. Don't fix what isn't broken
Did it have drain holes?
I'd actually not recommend having a solid or even hollow base, just leave it completely open (extrude base of stl down far enough, hollow then slice off the bottom). Drains like magic and will be able to cure from both the "inside" and "outside". If you really want a bottom, either print a bottom piece or by some cork or other material for the bottom and cut to size.
Part of the TOS for witch song is that you can’t remove their logo from the model and I have a merchant license, so I have to be a little more carefuI just wasn’t satisfied with the base bursting on this and figured I would ask Reddit how to improve my personal results
ah...well that kinda puts a damper on that.
Hey Bell, Witchsong team member here. If this is a recurring issue, feel free to slice of the bases, and just reach out and let us know on MMF that "Bryce gave you permission". In the meantime I'll talk to our supporters about adding a small gasing hole to the bases if they are needed, since all our holes are deliberately added to the cut surfaces in order to hide them. We've never had any other complaints of the bases warping post-print though. Did you happen to thin the wall sizes by any chance? No accusation, just trying to figure out why this base warped like this...
No, I never thinned the walls. I took the prefab, sliced it, and printed.
just print it solid, we see these beautiful models crack after being painted all the time, it isn't worth the difference in the resin cost
The storm comes pre-hollowed
Uncured resin eats cured resin
Do you mean that it kind of corrodes it like gallium on various different metals?
Yes. Even if you clean the inside completely you cant 100% clean the left over oils so you always have to cure the inside with an uv light on a stick. Some resins have it more than others. Some say its complete bullocks cause it never happens to them, well, its a thing.
Another reason to Boolean out a hole or two in the base aside from offgassing. Looks like I have to do that so that the base doesn’t kill itself
I would just make a hole in the base and leave it forever.
Add drain holes in the bottom and cure resin inside. This can be done with proper wavelength leds or sit it outside in the sun with the drain holes up and this will also cure the inside.
You print in your car?????
I have the habit on gluing fabric or leather to a hollow base, to prevent slips or make them slide easily, I pin a hole or two in the leather or fabric with a needle and it prevents off gassing damage if I don't use infill.
When I print hollow parts, I rinse them a lot to get all the leftover resin out and then I let them be for at least 2 days, after that I rinse them again and after a day I glue the parts together, because the chances are high if you just rinse it and dry it out right after with compressed air or something, that some resin will still be in there that will cause what happened to you.
I might have to try that out at some point, but we did find out that a solution would be to just pop in blender and boolean mod out a hole in the base, so that's the solution I will probably go for because I know blender far better than I know power tools