After getting frustrated with some mechanical issues in my FDM printer lately, and realizing that most of what I do with it are jobs probably more appropriate for a resin printer, I impulse ordered a cheap resin printer just to try if they are a better fit for me.
I have read that you need to be a bit more careful with a resin printer in certain aspects. I haven’t informed myself much about it yet, but from what I understand:
1 - You really don’t want to be in the same room while printing, and it should be in a room with a window open or in a balcony or something similar.
2 - Always wear gloves and a mask when dealing with the material or the prints.
3 - You don’t want the sun to ever hit the material for long until you have completed the print.
4 - Optionally you can get a curing machine that does a “second pass” of light, if you don’t get this you should expect prints to be somewhat “gooey” and less defined.
5 - Always clean the prints with alcohol and scrub them with some sort of brush to get residues off. This would come after the last past of curing.
6 - The prints are done “upside down” and you should set your supports accordingly.
Is there anything else I’m missing? Is any of that wrong, or are there any caveats about it? I would greatly appreciate any info about the particularities, and also any stories and experiences that you wanna share about resin printing.
Thanks!
So yes, most guides will tell you you need to wear a respirator while working with the resin, but personally I find it really depends on the type of resin I’m using. Generally if I’m just filling the vat then starting a print I won’t bother, same if I’m just removing my print from the plate and getting it ready to post process. But if I’m cleaning up and emptying the vat or I have a bunch of prints I’m working to clean and cure I’ll wear my respirator. Gloves are an always though.
A few additional items you’ll want:
- a silicon mat to work on to make clean up easier
- paint filters an a funnel to strain the leftover resin when you’re done printing and want to store it for later
- a plastic putty knife to scrape failed prints from the film (also good for removing your print from the build plate)
- high quality isopropyl alcohol (better than 90%, any less and there’s too much water which makes cleaning not work as well). I pick mine up at the local big box home improvement store (Home Depot, Lowe’s, Menards, etc) in gallon cans. Find it in the aisle with cleaning stuff and paint thinners.
- you’ll want to put some isopropyl into a bottle just for cleaning your equipment and work area. I use a spray bottle that I also use for cleaning the build plate on my FDM printer.
- extra film since you’ll likely scratch yours after a few failed prints
I found it takes some practice to get the prints setup and sliced for good printing, way more than when I later got into FDM printing, expect failed prints. Supports are much more necessary than on FDM prints, but the fact that it’s upside down doesn’t really make a difference since it’s still printing bottom to top, you just need to be careful of islands as you print since it’s all printed a full layer at a time. This also means the only thing that increases print time is height, something that is the full area of the build plate but only 1cm tall will print faster than a 10cm long needle printed straight up and down despite being way more volume. So fill up that build plate with multiple models to save time.
It does require a lot more post processing than FDM, like at least as much work as prepping, slicing, and actually printing. I can take something off my FDM printer and it’s ready to use, I need to account for at least 30-60 mins of work once my resin prints are finished to clean them, cure them in my UV box, remove supports, and then clean up the vat and printer. I tend to batch print for this reason, getting 3-5 sets of items ready to go and then running them back to back over the weekend. This means I only need to clean the printer up once.
You’ll want to print (likely on your FDM printer) an adapter to allow your build plate to be hung at an angle to allow resin to drain into the vat once a print is done. This will waste less resin when you clean.
This is all just off the top of my head and written on mobile, so apologies for and autocorrect mistakes. Feel free to ask for clarification on anything.
Dang that’s a lot of useful info, thanks!
So am I understanding correctly that you can leave all the cleaning/curing process for another day? I can print a set of figures and store them somewhere fresh off the plate on monday, and do all the post-processing stuff on friday? Because if that’s possible that is pretty great, I had kinda assumed that the curing and cleaning was required immediately.
As long as they stay shielded from UV you probably can, but I wouldn’t leave them for days. I’ll often leave prints running overnight, they finish sometime while I’m sleeping and I’ll hang them on the drip adapter for a few hours once I wake up and then clean and cure them later in the day without issues. I also typically print in the basement where’s there’s no windows or light so no real way for UV to leak in and partially cure the resin. If you’re printing in a room with windows you have more of a chance of sunlight impacting the prints before you wash them so keep that in mind (the orange/yellow covers block the vast majority of UV but aren’t 100% perfect).
Ah ok thanks! Makes sense. I’ll do my best to shield it from light then.
Thank you so much for the info!
You need to clean with IPA before curing. Also keep in mind that it’s better to make sure it’s well dried before curing. Otherwise there may be whitening residue around wet spots.
Another tip is, if you are going with hollow prints, you need to put drain holes. It’s better to use some kind of uv light that can enter from these holes to cure too. Holes are pretty important. If you forgot the print may break, leak crack in time.
Also do not forget, suction cups are your enemy. They work against a successful print.
Thanks for the tips!
Huh, I was always told to add a hole to my models and I never really researched why, now I know lol.
Sounds like I might wanna add small holes somewhere in the upper area because I’ve always modelled the holes in the bottom of the base and I’m not sure how much that will help.
Oh I didn’t know about the concept of suction cups either, I’ll try to be careful with that thanks!
Don’t have a resin printer myself, but there’s one more tip that can save you some money in the long run.
As already mentioned by others, you should use pure IPA (ideally the 99% variant) for cleaning your prints, but that stuff can get quite expensive. To keep your IPA “waste” to a minimum you ideally have 2+ containers that you can seal airtight and that are big enough so your build plate + attached prints fit in.
Container #1 is your “pre-wash” for everything right off the printer. It will pick up most of the uncured resin and due to that discolor pretty quickly, but that doesn’t matter much.
Container #2(+) is/are your final wash before curing, since you already removed most of the uncured resin in #1 they stay clean a lot longer and you don’t have to replace the IPA that often.Oh, and about your point #4: AFAIK curing is not optional but pretty much required since the amount of UV light the printer itself uses is by far not enough to fully cure/harden the resin. But you don’t have to use one of those expensive “curing stations”, I’ve seen more than enough folks who built DIY versions with UV LED strips, tinfoil and sometimes a (DIY) turntable.
Oh ok, I guess I’ll get a cheapo setup with a manual light then for the time being, thanks!
It’s looking like I’m definitely gonna have an interesting visit to the home improvement store lol
