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Oh ouch that's a painful experience in 3D printing!

I can however tell you exactly why its happening.


Uncured resin chemically reacts with cured resin . This reaction can take days, weeks or even months to take place, but it will happen. When it happens it causes the cured resin to weaken and eventually crack open and the wet resin inside spills out.

For this reason any hollowed models MUST have draining holes so that resin inside can be drained out and also washed out with IPA during the washing phase after printing.

You also need to have drain holes big enough to flush properly, tiny ones or just one hole won't flush properly and will leave resin inside which will tear out in the future. If you can't make at least 10mm holes in the model to drain it, I wouldn't bother hollowing. The tiny saving in resin isn't worth the risk of failing and cracking - as you've directly experienced.


I never bother hollowing things like standard horses, infantry or such - the gain in not used resin is tiny compared to the potential fallout mess and there's often little to no space to put good proper drainage holes on. You might get get away with tiny ones, which can then sometimes dribble IPA/resin for ages and even then still crack open.



Another thing with hollowing is that when you hollow you can create voids in the model which aren't connected to the main drained area. These isolated spots either need their own holes or you have to use something like lychee hollow blockers, which basically tell the software to not hollow in those regions (after applying a hollowing setting).












That all said I've had my own 3D print pains including and not limited too

1) Learning all about how important heating and the method of heating! Esp after getting started during a warm patch in autumn and then hitting fail after fail for ages due to temperature.

2) Not having enough lift height - did this one a few days ago on my new printer as I loaded the buildplate up and boom - several parts failed to separate from the FEP and failed ot print. All because my lift height was ok for small prints but not big ones with more pull on the FEP. Raised it by 2mm and all fantastic now.

3) Taking 1 second off my exposure time by accident and then trying to problem solve everything else because of random fails and such. Totally on me, but still wasted a bunch of resin on it.


3D printing is painful because fails can so easily happen and it takes time to learn all the quirks and how to problem solve through the fails to work out what went wrong. Esp as sometimes its not one thing but several things.

 Mothsniper wrote:

 philmorgan75 wrote:
Hi Everyone,

As the title suggests, I have been having a number of issues over the past few weeks that have almost made me cry. I started 3D resin printing last November and there has been a steep learning curve. I thought I could save myself some resin by "hollowing" out the models I was printing off. I spent a number of days and a number of bottles of resin and printed off lots of models over the past few months. Over time, I started to notice models breaking apart and liquid resin pooling on the base and sometimes overflowing. I thought at first it was a one off but it started to happen regularly. In July, I reverted back to printing without "hollowing" and have spent a lot of time reprinting models I have had to throw away. Unfortunately, over the past week, I have had to throw away 20 completely finished models and I feel gutted what with all the time and effort I've put into finishing these. Here's a few examples:

Spoiler:

I had finished painting 5 of these Rough Riders and have ended up throwing all of them away :(



I had finished another "Red" Squadron of Rough Riders - I have 2 left. I'm too frightened to put them away as if they crack and leak, its almost impossible to clean up and if liquid resin goes on any other model, I have to throw that away as well :(



I loved painting these Solar Guard replacements but have had to throw away over 20 of these this week. I now have to find the files and reprint them and add them to my painting pile.



Although most of these look ok from afar, when you look at them closely, the jumpsuit has cracked and resin is starting to pour/dribble out of them (like a touch from Nurgle). So before they make a huge mess, I've removed and kept the bases and chucked them in the bin this morning.



This vox operator looks like he is so scared that he's wet himself



These look fine but have started to dribble. They've been de-based and thrown this morning.



Again, these look fine, but liquid resin has started to dribble so they have been flushed out of the nearest airlock.



I loved this model and really enjoyed painting him. I'm gutted that I have to throw him away.



And finally, this model has cracked in 2 places, so had to go.

I'm making light of what has happened but it's really upsetting when things like this happen. I'm trying not to dwell on how much time I have lost on these models and want to take this as a learning experience. I am now in the routine of checking all of my printed 3D resin models every morning to make sure I haven't got another model that needs to be thrown. Unfortunately, my "hollow" resin prints have been cracking over the past 6 months and as I have reprinted replacements, I stupidly put them in with the hollow ones - now I don't know which ones may crack in the future. Does anyone have any suggestions on how I can prevent the already printed hollow models from cracking sometime in the future?

Please fell free to share any of your own modelling mishaps on this thread.

Wow. I feel your pain...
I just received similar solar guard replacements order from aliexpress, I do not know what resin they used to print em, how they cured them, but now I am a bit worried will my models will leak overtime too?
So what causes the leakage? And how to avoid it? I remember a warning to keep the models away from the sun light. (something about over curing, long exposure will crack) but leaking?

The leaking is because the OP chose to hollow them, a reputable merchant shouldn't have hollowed those prints so they shouldn't leak.
Check my earlier post for more details.

As for sunlight its not a risk - you CANNOT overcure 3D printed models.
What IS true is that fully cured 3D print resin is often quite brittle (more so than many people appreciate, esp if they come from a background of PVC or GW plastics). Some designs are also honestly not well designed for resin and playable omdels and can feature very thin/fine details that can be impractical/risky in gaming.

I think Mars are great printers to start with, but once you want to print tanks/mechs and such then you want to start considering a 9inch build plate - so the likes of Phrozen Mighty; Elegoo Saturn and similar sized printers which make things like dragons, tanks, titans and such a LOT more practical to print with.

Also make sure everything just sits in the sun and gets UV blasted before throwing it out