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@the_scotsman: 10s for .05 layers on the Mini 4k, which is a monoscreen, is way too high for non-bottom layers. Not only will you significantly cloud xy details, as skchsan mentions, you'll also significantly reduce the life of the printer itself. If this was a non-monochromatic screen, 10s would be reasonable, but that's far more than is really recommended.

@Overread: Ok, the Phrozen Aqua 4k on the mini is what I've used too, and I am usually doing 2.6-2.7 at 50um. I do 6 bottom layers, though, and have started playing around with adding 4-8 transition layers (not sure if that's made a difference yet, though). So I'd double check your leveling, and also ask what temperature is the room in which you're printing? If it's cooler, then you might have to crank up the exposure time a bit.

If you can post a pic of your failure, it might help us figure out what might be happening.

Edit: Oh, another thing you can adjust, and might be a good place to start, is the lifting speed. 80mm is... iffy. I dropped mine to 50mm and had much less ripped supports and so on. Also, I assume you're still using the stock FEP in the vat. I've heard significant improvements there can be had by switching that out to an nFEP. I've ordered some but haven't replaced yet, so can't speak directly, but a lot of folks in various FB groups and Reddit say it makes a big difference.

I've been looking around for nFEP but either I'm searching the wrong term or its not as accessible in the UK at present. I do think its what I'll replace the FEP with once this one dies on me as I've also heard good things. Though the lubrication I'm using is also seeming to make a big difference as I'm not seeing the big strain on the arm nor the super loud sucking sound others describe.

My second casting has gone well, though now I'm tackling it feeling a bit rubbery/soft. Which from looking suggests either that my cleaning wasn't good enough or that the part needs more light exposure. Once I've got it cured a bit better (or before) I'll get a photo of it up. It's cast well but perhaps not yet perfectly.

 Overread wrote:
I've been looking around for nFEP but either I'm searching the wrong term or its not as accessible in the UK at present. I do think its what I'll replace the FEP with once this one dies on me as I've also heard good things. Though the lubrication I'm using is also seeming to make a big difference as I'm not seeing the big strain on the arm nor the super loud sucking sound others describe.

My second casting has gone well, though now I'm tackling it feeling a bit rubbery/soft. Which from looking suggests either that my cleaning wasn't good enough or that the part needs more light exposure. Once I've got it cured a bit better (or before) I'll get a photo of it up. It's cast well but perhaps not yet perfectly.

Glad to hear you made some progress.

That Phrozen 4k resin is definitely kinda rubbery after the wash. Plopping the part under a UV lamp (I was using a nail curing thing, but recently got an Anycubic Wash & Cure 2.0) for about 3-5 minutes hardened it up pretty good. I think it's slightly tougher than most resin minis I've got, so... It isn't going to be tough as HIPS, though.

If you see any spots of still shininess on it after washing and letting it try, then that's likely some resin still in there, and might need another bath. Curing it with resin still on there will lead to longer cure times and probably some white "gunk" showing up, as well as possibly leaving it a little more rubbery.

Here we go with the first successful cast. I have to say that many of the horizontal lines on show don't actually appear to the naked eye as such. I'm not excusing them, but to the naked human eye they hardly appear, even under a bright light. I suspect under a layer of paint they'd hardly appear at all.

Some of the finest vertical rods have printed, but also flopped over, which I think might be as a result of being as thin as they are making them very vulnerable during washing etc.


Overall I'm very pleased with this second result!

Overall that looks pretty decent. The lines are a bit more than I've seen on my 50um prints, and might point to slight wobble in the build plate. On that piece, some of those rods are kinda expected to fail from what I've read. Out of curiosity, did you have AA turned on for this one?



Automatically Appended Next Post:
Oh, and yeah, layer lines tend to show up more in ultra close up photos like that, when they may not be as visible under naked eye, and after a coat of primer often mellow out.

I'd not turned it on and not thought to check. It seems it was turned on by default to the following:

Grey level 4
Image Blur - not ticked

Rubbery feel means its not cured properly (or if problems persist, SHAKE YOUR RESIN. despite the homogenous nature of printing resin solution, it still seems to separate to a certain degree). You can either resolve the issue at post processing, increasing (normal) exposure, and/or matching the viscosity of your resin with the lift speed. The latter often happens when the resin is too thick, it can have issues rolling down large surfaces of your print as the print gets 'extruded' upwards. These excess resin get indirectly cured and do not receive proper lighting, so it only gets partially cured - this issue is also commonly observed when you have surfaces that are parallel to the build plate, where the resin pools because doesn't have the slope to roll off of.

Oh and one thing we didn't mention yet - unless you are using water soluble resin, do not let the print touch water during post processing and don't put it under curing lamp prior to the IPA fully drying off. It often yield less than desirable surface finish (would matter less if you're painting over).

Posted a late-night update in my blog post thing that I'd appreciate if anyone would want to hop over and comment on. There's an actual model sculpt that came out of the system, a failure and a few things on settings and what I've thought of things thus far.

https://www.dakkadakka.com/dakkaforum/posts/list/796266.page#11059104