Lots of people have already commented on the correct solution, which is that you are waiting too long and curing a mixture that is too high in resin. My recommendation is that you just have several stages that you cycle through. Because of your industrial level of use, you need to think of this on an industrial scale. Bucket 1, clear to mostly clear IPA. Bucket 2, Used two days - sit in the sun (or in the curing machine), Bucket 3 - resting to get the resin particulates down, bucket 4, filter through the large filter first to get the big pieces out, then filter through a brita (or cheaper filter to clear it and go back to being bucket 1). Additionally, your methodology for testing could use some work. Instead of waiting for days to test, just pour resin into ipa directly. you now have a mixture to test with.

I was also searching for some good filtering solutions, but so far they were more expensive than just to replace the IPA. Thanks for your tests, are very valuable 👌😊

Being a Chemist, that’s what I would have suggested, a distillation column.

Hey Uncle Jessy, I have been recycling my IPA with some level of success. I normally can recover about 70% of the original IPA. I hope this help, here what I do : 1) I do not let the IPA get too dirty. I normally recycle my IPA after around 5 medium size prints. 2) I keep two batches of IPA, one that is cleaning the parts and one that is recycling, this way I do not have downtime. 3) I do wait for a day or two for some of the resin to settle, this is the main reason why I keep two batches of IPA. 4) After the dirty IPA rested for a couple of days, I let it out, on the sun for curing. The sun may cure slower than the UV, not really sure, but as the IPA cures, I can see the resin being attracted to the container walls and the partially clear IPA left in the center. I usually leave outside for a day. 5) After curing under the sun, I filter it with paper towels, two layers. 6) After filtered, I store the recovered IPA for use and let the solids out to cure and dry completely before disposing. PS : I did have one time where I got the gelatin you got, and I concluded it was because there was too much resin, so that is why I try to not let it too dirty. I also do a two step washing. The first step is more to take the majority of the resin (Old wash & Cure - 1 min) then I move to the second wash (New Wash and Cure - 6 min). It may be overkill, but I basically need to recycle the first tub, the second one really takes a long time before it get dirty. I also remove my supports before any washing and I never printed anything hollow. Just letting you know, so you can have an Idea how my dirty parts look like :-) That did not sound really well ... :-)

What I do is have two containers for my Elegoo wash/cure machine and I swap them once a week. I then leave the swapped-out conatiner to sit for 2-3 days to let most of the resin sediment fall to the bottom. Problem is, these containers have a spinner at the bottom that makes it very difficult to scoop out the sediment, so I ended up printing a false bottom / shallow basket that I put into the container at the bottom (resting on the spinner). The sediment collects on top of this and then after a few days you can pull it out - bringing most of the sediment with it. This doesn't filter 100% of the resin out but gets most of the big particles out. The IPA will go back to being reasonably see-through from murky-opaque looking like yours, and I then top it up with new IPA (~15-20% of container volume worth). I now go through like 2-3 litres of IPA every month instead of like 10 litres before I used this method. Big saving with what 95%+ IPA costs round here..

I’ve been curing what’s in the ipa after every time I use it then filtering it out using the paint strainer. Now I’m pretty new to all of this but it’s been staying pretty clear so far. I Enjoy all of your videos!

just an idea out of the box, i clean my resin prints with one cheap airbrush and ipa. fill the cup of the airbrush with the ipa and spray direct on your print, once the ipa is empty just spray whith air coming from the airbrush until the print its dry, then you put that on th uv light and wualaa your print turns awesome and you save a LOT of ipa = save money. i been doing this since i started to print and never have a problem or lost quality of my prints. love your chanel mate and all of your techings. keep ir up! greetings from argentina

I use a water distiller. Works great!

It isn't always about the wins Uncle Jessy, it's about the experience. You could be helping someone else avoid some of the trials and struggles you're going through. Awesome video and looking forward to the Part 2 showing more ideas and hopeful successes! Keep up the great work and love your content

I saw a guy on u tube use a water distiller with the ipa. It is for sale on amazon. The results were fantastic. I am going to try it. Good luck.

Goobertown hobbies is a PhD chemist and a rad guy, maybe hit him up for a collab?

You should try to contact the channel "Nile Red." He's a chemist and this seems like a perfect collaboration. Also a cheap easy distillery will work, but has inherent risks.

I run a print shop on Etsy (don't worry, not gonna plug it! lol), but I have tried everything I could to save IPA because I spend as much on IPA as I do on resin. And with the volume I go through, that's a LOT of IPA. Here's the best solution I've found. It's similar to something that you mentioned in the video, but with a few changes. I use a two step cleaning process. I rinse every print off in a bucket of "used" IPA first (see below) to remove the majority of the resin. This helps me extend my IPA usage by a couple of days by limiting the resin that gets suspended in the "clean" IPA. After the initial dunking in used IPA, I transfer to an ultrasonic cleaner with my clean IPA. I change my IPA every 4 to 5 days. By "change", I mean start the rest of this process. 1. I have 3 large sealed containers that I rotate through, for dirty IPA. When it's time to change the IPA, I dispose of what's in my "dirty" bucket (at this point it's more resin than IPA). Then I pour what's in the oldest sealed container of IPA into the dirty bucket. By the time I pour it, that container has been sitting for roughly 2 weeks and the alcohol has decanted from the resin significantly. This is now my new first wash "used" IPA. 2. Now, I pour the formerly "clean" IPA through a metal stainless steel filter strainer from Sovol (on Amazon for about $14...not affiliated at all, just like the product) into this now empty sealed container and shuffle it to the back to decant for 2 weeks. The filter is more to remove any chunks of supports than to remove any resin. 3. Lastly I fill my clean container up with fresh IPA and start the process over. Is it perfect? Not at all. But at the volume of printing I do, I was changing my IPA every 2 to 3 days and this has allowed me to double that. Since I'm selling prints, I have to try extra hard to make sure that I'm not stretching the wash out too far and sending my customers sticky prints. If you do find a way to reliably clean IPA well enough to actually reuse in the ultrasonic cleaner, that would be phenomenal. Hoping you find the magic alchemical formula. Thanks for all the videos!

For testing purposes, could you simply stir some resin strait from the bottle into the IPA?

I have a variable temperature water distiller that I use and it’s quick and reclaims a lot of ipa that is completely clear

Try a centrifuge, spin it in a sturdy container at a very high speed to force seperation. Try curing after you see separation. While spinning and while not spinning

I have been fairly successful filtering my IPA. I try to use 90+% and cure it early and often before filtering it through the paint strainers. I do this 2-3 times before I get clear,, clean looking IPA. I usually have a few different "cycles" always going so when I'm curing the resin in one batch of alcohol, I'm filtering another, and using another. It's frustrating for sure when I get failed batches, but early and often is the best suggestion I have for you.

Like you, I've experimented and found a process that works for me. I purchased 2 gallons of IPA. 8 good sized mason jars. And last 2 very large glass jars for storage of the IPA when not in use. No filters needed in the process. When my IPA gets cloudy due to use, I pour into the mason jars. Cure each mason jar for 10 minutes in my cure station with the lid off the jar. Place the lid on the jar, shake jar to get resin off the side of the jar, and then let sit for a couple of days. The IPA floats to the top and the resin is semi solid on the bottom. The now cleaned IPA I store in a large glass jar till needed. The resin at the bottom I scrape out with a rubber spatula. And it's an ongoing process. Every week I have enough clean IPA to work with and during that week I'm cleaning the dirty IPA. I haven't needed to buy any new IPA for months now.

I have been struggling with this video for a while now... Hopefully this at least helps some of you out there in terms of WHAT NOT to do. Would love to hear what suggestions you all have! Also - a huge thankyou to Elegoo for continuing to support my crazy project ideas... even when they completely fail... for now ;)

Polymer guy here. I enjoy your channel and your approach to this topic. You are battling three elements in you used IPA. First, the solubilized and unreacted monomers. Those won't come out without distillation or vacuum distillation. Second, the photo initiators are in the solution as well. Same as unreacted monomer and won't come out without distillation. These two problems are why you got the gelled material rather than a precipitate. The concentration was probable too high in the IPA, too. Third is the pigments. You can filter those but you may have to reduce the filter's efficiency to less than 10 microns. You could use pool filtrate (diatomaceous earth) in a filter press. In the end you may be able to filter the particles out but you won't be able to filter out the monomers and photo imitator. You will need to heat distill or vacuum distill the IPA. You could use an inhibitor such as MEHQ to prevent gelling in a distillation set-up if you use the IPA with the current level of washes. Don't know of this helped but best of luck!

I have a couple large, clear containers. I put the dirty IPA in one, and put clean IPA in the wash and cure. I point a UV light at the dirty IPA container (the one you suggested in another video) for a hours at a time until it becomes clear. If it takes days, it doesn't matter cause you have clean IPA you're using right now. When the clean IPA becomes dirty, put it in your second large container and your newly cleaned IPA is strained and put into the wash and cure container. Proceed to rotate between your containers, adding fresh IPA if you start to run out. I do tend to notice that the strained IPA becomes murky if you fully strain it into the container, so I usually don't pour all of it back in to prevent that. I don't think you can get it fully clean like fresh IPA, but it's definitely able to be used.

Easiest way is put the IPA in a clear plastic bottle and let settle the resin to the bottom and then put in the sun for a week... filter and clean IPA... for me works Another method that a friend of mine uses in his print farm is converting a fish tank as a clean tank and use some carbon filters and the water pump to clean the IPA, only one thing must be change are the plastic fititngs because IPA destroy the plastic.

Leaving it to separate, then pour the top clear part through a filter and let it stand again, seems to be decent enough. Leave the residue out in the sun to cure in the container and then put that through a filter. You'll need some extra containers and a bit more IPA but such is life.

Method that works on me: Use coffee filter one layer to filter the crumps > use the Brita water filter to refine a bit > use a clear glass jar and UV light it for 5 mins and let it sit for a night > put it into the UV light machine without moving it vigorously for 5-10mins > shake it and UV again for 5-10mins > let it sit for a night > you will see the alcohol is crystal clear > filter it with a new Brita water filter, make sure the bottom resin don’t get in > then you get a 99% crystal clear alcohol, you can double check by putting it into the UV machine again, you won’t see any crumps or cloudiness anymore. Good luck ! FYI don’t uv light too long when it is too cloudy for the first time, they will bond together too fast with High concentration to form a jelly like video above. Depend on the concentration of the solution, repeat the follow steps a few times if necessary. It will be crystal clear again.

Did you ever find a solution for your setup? What I do is very simple and you sorta touched on it. I have a number of clear Gold Peak tea jugs. What I do is pour my dirty IPA into it and let it sit at a window where it can get good sunlight. By the end of the week, the resin has cured and I then filter it a few times through coffee filters. But my funnel is large enough to hold a mesh strainer, to which I place the filter. This way most if the filter is used and speeds up the process. I also let it filter near the window to help cure any resin that gets through. At the end, my IPA is near clear and reusable. Without a chem set, there is no way you're going to perfectly clean the IPA. It needs to be noted that I don't use my resin printer anywhere near as often as Jessy does. I also use mostly clear resins or my own 'Monster Batch' resins. With my clear resins, I enjoy adding paint or ink pigment powder to it. This way I can get a nice glittery effect if needed. But cleaning the IPA from this resin is more difficult.

I have a solution that works fairly well for lower printing needs. I use a bit of a combo that I have seen from various youtubers. I use a 2 wash IPA system. The first one washes off the primary residual resin, the second I put only clean IPA in never recycled. When the first bath needs to be cleaned out I put it in a giant pickle jar (80oz/2.5 qt) and let it sit in the sun for a few days then I strain it through a coffee filter, put it in the sun for another day or 2 and strain again. The result is slightly discolored IPA that I use in the first bath. Most likely it doesn't need to sit in the sun so long but I usually only print on the weekends. I have also come across the goo you mention but it settles to the bottom of the jar and I filter it out using a drain filter then let it cure on a plate or something.

The reason you were getting the gelatin material is because the IPA is a mild solvent for the resin which is why it cleans so well. This being said, the resin cant cure as fast as it is being broken back down to liquid form. I started filling a 3 gallon bucket up with used solvent. I use a mixture of 60% acetone 40% IPA. The mass of the dissolved resin is still heavier, so after about 2 weeks there will be a few inches of clear IPA at the top you can siphon off with a generic fuel line. The resin will begin to form a slime at the bottom that needs scraped out every other month depending on use. Your videos are always so awesome and fun to watch. There are so many of us out there that wish we could personally thank you, for the knowledge you've help spread. Keep up the great work!

I have done this successfully several times using just coffee filters and my cure station. What I do is let the IPA sit for a few days to let it settle (this seems to be super important) and then throw the IPA in the cure station with out disturbing it. This sometimes sets up into a gel like yours but not quite as stiff. I just break up the gel with something and run the IPA through 3-4 coffee filters stacked together. I think when you let the IPA sit and settle the resin collects at the bottom and makes larger particles that can be filtered out easier. If you don't get the IPA so dirty the gel wouldn't be as stiff and might be recoverable. Like a lot of other people have said, one big problem is that you are waiting too long and the IPA has too much resin in it.

I just experimented with the idea of curing the resin then filtering - Works well but you probably want to do it when the resin to alcohol ratio is lower so that it is easier to separate out. I just used the 20w CFL blacklight that I have to cure it out then filtered through a coffee filter. I'm probably gonna experiment with different filters at some point and see what luck I get

I have an immersion circulator. Mostly used for sous vide cooking. I have been using water washable resins thus far, but will have to branch off into IPA soon to make stronger prints. I intend to use old 2 liter bottles with lids and some plastic tubing from a hardware store plus a couple of plastic barbs and epoxy to make a very crude but very safe still. Drill holes in the lids of the 2 Liter bottles and glue the barbed plastic ends into each one. Since the immersion circulator has only a water heater of sorts in it, it can safely heat the water to nearly boiling in a very controlled manner, which will heat the 2 liter bottle filled with dirty IPA in it. That will be contained in a large pot or some other cylindrical item that keeps the top of the 2 liter bottle vertical enough to not have it spill dirty IPA into the tubing and only allow vapor out. The vapor would collect in another bottle with a sealed similarly barbed lid on it. It would evaporate almost all the IPA out leaving mostly resin behind and you can then cure and toss that crud filled 2 liter bottle. Just keep the barbed lids and the hose for re-use and have a spare 2 liter bottle ready to cycle in when needed. This would be working as you do other things, so it's not an active process that you really have to do anything to manage. The temps are simply maintained and the evaporation happens over time and moves the alcohol into another cooler container as you do other things. After a set amount of time, you can just collect the good IPA and add more as needed and keep on trucking.

To conserve on IPA usage like others have said do multi stage cleaning before you put your uncured prints in whichever Wash and Cure station you use. I go one more step to save money and I use simple green or mean green for the first stage with warm water and brush off the majority of uncured resin then I transfer my prints to a second stage IPA bath to get off the excess simple green that some complain making the prints slightly sticky. Then after that bath I transfer my prints to the wash and cure station that way I go through less IPA as most of the uncured resin is scrubbed off in the simple green or mean green. I have extra IPA bath containers that I will rotate in and out of circulation when the IPA starts to get too murky I'll move that container outside and let the resin and IPA seperate and then strain out the resin from the IPA. I'm not 100% sure of it's safety of the contamination of simple green into the IPA 2nd stage bath, from what I've looked up I believe their isnt any safety risk of the two mixing, but maybe someone more knowledgeable will be able to answer that.

You could use a spinzall centrifuge to separate the resin out of the alcohol since they should have very different gravity.

i used to filter it after each week of use. now i tend to let the ipa sit in containers for a couple of weeks then filter it off. i have never let my ipa get to that colour. at the moment been using methylated spirits for cleaning the prints.

I've gone through all of this with the exact same results you got. The one and only thing I've noticed that could possibly help is that I store my dirty IPA in an area that gets a bit of indirect sunlight. It does not sit in the sun and the window has a tinted film on it, but I do notice that after a day or so of sitting that a thin film of solid-ish materiel will form on the side of the tub facing the window. The whole tub does not gel up, just a thin film forms along the side. I know it's not sediment because the IPA is still relatively clear and there is not a film building up on the bottom. Only the sides. It comes out easily and I expose it to finish curing it under the UV light and it goes hard as you would expect. I haven't done extensive testing on this so I don't know if it's helping or not, I just made an observation. This is also not heavily used and saturated IPA. Perhaps that has something to do with it, like you mentioned toward the end. But I have tried various methods of filtering and short exposure to UV and nothing works. Even short exposure to UV will form a film which I then fish out leaving the remaining liquid. I expose the remaining liquid to another short round of UV and keep repeating. There is never any IPA left. I think that the molecules are just so small that they are unable to be filtered by easily accessible methods. And once you get IPA saturated with enough resin and expose it to UV, it just polymerizes like you've seen. A distilling method like you mentioned would work if there is still IPA left to evaporate out, but it would be highly explosive and there may actually be laws against it in certain areas. Another possible method would be something like osmosis or high pressure filtration, but that only stands a chance if the resin molecules are noticeably larger or smaller than the IPA molecules. I have no idea what the sizes of them are and I suspect it could get rather costly and messy. At this point I've given up cleaning or filtering it. I keep two or three tubs as progressive wash stations and I move from one to the next, getting cleaner as I go. Once the first, and dirtiest, one hits a certain point and it's not cleaning well, I put it in the sun for a couple of days and just let it gel and dry out. The whole tub goes in the trash once it's all cured and I've already moved the others up the line and started a brand new tub with clean IPA as my last rinse before curing.

I use the wash and cure station as well and what I do is pour the dirty IPA into a sperate container after a few uses Usually about a weeks worth of printing for me ( a empty 2 liter works well for this). let it sit in the sun for a few days and cure. You will get fine particle that will form. You can then filter that out and get "cleaner" IPA there are still some residue so it isn't pure IPA any more but it doesn't have a high enough concentration of resin to keep curing, if you do this you can reuse the IPA multiple times. after filtering I let the filtered material evap fully and cure in the sun. I can cycle between batches of the cleaned IPA solutions adding fresh new IPA occasionally as I go. This method has worked well for me. Pleas note I don't print as much as you so you might need to do that every day or after a day or two with the amount you print. This means you might need a few "batches" with the amount of printing you do. I have also found that some resins react differently so the type of resin you use has an effect on how often you need to clean it. The main problem you are having is that you are waiting two long between cleaning. As a test maybe you should pull a sample out each day and try curing that and see what the critical point is? Maybe you could print a centrifuge that you could make it forcibly separate out faster? I am also using the 99% ipa for the most part that I have to get ordered in. The local stores usually only have 71 percent or if i am lucky 91. I have seen you use 71% a lot so maybe that has an effect on if it jellos or makes particles when you cure?

Funny enough I was doing the very same thing today. I had around 7 bottles of dirty IPA, left them in the sun (with the lid still on) for a few hours. The IPA separates from the resin and sits on the top of the gunge. I then used a coffee filters in a funnel to pour the separated IPA into a spare bottle. Once I gathered as much IPA as I could from each bottle, I put the lids back on and let them dry some more. I had varying results with each bottle, some slightly cloudy, a few orange tinted but I did manage to successfully get one bottle of clear IPA back. All the best of luck pal 👍🏽 Love your content 💯

So my thoughts: I think you are getting gel in the wash and cure because it is mixing when it cures. Might try removing the plate from the bottom. What I am waiting until I get an fdm or larger printer for (only have a mono), is to build a funnel that screws onto a standard Mason jar, then a spout for the wash and cure station (I have the anycubic w&c 2). I was planning on using Terry cloth towels in my funnel with a screen material layer as my first stage, then wring out the towels. Then I was going to run it through a paint filter. Then once complete I was planning on either leaving that jar in the sun or removing the turntable and doing it in the w&c station. I was expecting that it would have to be left long enough for the resin to separate, but with Mason jars I just keep a rotation of fluids, and once the liquid clears and slowly cures at the bottom, then reuse it, then just run the process weekly. This is not an ideal solution, but filtering is only going to get large particles. To remove the really small stuff it has to separate naturally, which is time consuming. Just my two cents for a project I wanted to do. I appreciate that you are conquering some of the trial and error.

OK, I'm only half way through, but it looks like you'll need to build a distillery to have a chance of rescuing the IPA from the grips of the dissolved resin.

Hi Uncle Jessy. Appreciate your videos. My experience has been that there is no fast solution. But there is an effective solution... When my IPA gets murky, I transfer it into a one gallon clear water jug. In my basement where my Print Lab is, I have a large window with a large sill. I put the water jug in the sill, refill my cleaning station with fresh IPA, and keep going with life. After sitting in the windowsill for about a month or so, the IPA has separated from the resin, the resin has solidified, and I am able to Simply pour out the clear resin and throw away the jug. At any one time I usually have about four jugs on the windowsill doing their thing. This means I have to keep four or five that's of IPA on hand, but once I get to that point I just rotate through the used stuff. Cheap and simple. This has worked well for me. Hope it helps!

I have also been experimenting on this and was excited to hear you were looking into this. I'm probably on 400+ resin prints over the last year. Currently, I pour my waste resin into a 5 litre bottle and let it sit for a week until the next lot of IPA needs putting in. Before I put in the waste IPA, I carefully pour out some of the used IPA without disturbing the sediment at the bottom. It works ok for a second run but needs replacing much faster than virgin IPA.

Hey Uncle Jessy, ive been using Ez Filter system. Its basically a brewery set using carbon filters. Its 2 containers stacked with a filter strainer with carbon pallets in the middle. I transfer used IPA into the top bucket and just wait a few hours. The liquid in the bottom get clearer every use. I repeat this till I reach a clear liquid. After about 3 or 4 times the carbon pallets have soaked up most of the impurities and I just leave them in a clear container in the sun and bring them to our local chem dump. With kind regards, fellow resin printer fanatic from the Netherlands.

Took a gamble and purchased the water distiller. It works! I got very clear results.

Don't know if you solved your issue with a practical method but I got a two part method I like that can be done relatively quickly ( I'm not waiting days for this). Dissolve some aluminum sulfate into distilled water then mix it up really well, then mix it into the IPA and I just let it stir for 30 minutes using my cure station for this. I dump the mix into a bucket, and let it sit there and stir it occasionally when I remember for the next half hour or so until I feel warm and fuzzy that the resin precipitated out of the IPA. Between cleaning the cure & wash tub and normal household distractions it's usually settled for me. I pour off the cleaned IPA into a couple big pickle jars (and use a dedicated turkey baster for the last bit if I feel it's worth the effort). I could strain it, but I haven't yet and I'd rather just cure the leftovers in the sun and bin it. In the jars I dump some brine water and stir it up again. This step dries the IPA out letting the salt water pull more water from the IPA and it makes a nice layer to tell the two apart leaving me more concentrated IPA than when I started the whole thing which I see as another reward for the effort. When done right you'll be edging toward a layer of 99% IPA, but I have neither the means nor the inclination to quantify my results... Which I guess is odd for me and my number chasing ways... The salting step I either wait for about 30 minutes for this step if I'm impatient or let it sit till the next day when I'm willing to deal with it again. In the jar you'll see within minutes the separate IPA layer and water layers making it easier to get just the IPA out and store it. As for the mixtures, the salt water I just use kosher / iodine free salt dissolved in tap water. For the flocculants I mix 50 grams into 1.25 cups per 2 liters of IPA, (for ~$10 for a 1lb on amazon you can clean/improve up 18 liters of IPA). I should try mixing both steps into one some day and see if it works out. if the resin wasn't cleaned from the IPA well, you can tell on the salting step because you have clear salt water to compare your IPA to.

VOG did a video on his process a little while back so maybe he has some suggestions. There are two printable funnels on etsy that let more of the filter, well, filter, that seemed to work ok when I tried this with water from water washable resin. If you re-visit this I would try not waiting quite so long or at least adding in a bit of fresh alcohol so it doesn't gel up so much. And possibly so a sample batch and if it gels don't run the next batch as long. Hope you have some more success on a re-visit!

I'm not printing nearly the amount that you are, and I'm sure somewhere in the comments someone else had mentioned this, but what works for me is a large (2 gallon) glass container with a lid and a spigot just like you'd use to make ice tea or lemonade. I picked one up a local store for about $10. Pour in the dirty solution from your washing station and let it sit (for several days or a couple of weeks). The resin settles to the bottom. The spigot is about 2 inches from the bottom of the container so when I refill my wash station only clean (or mostly clean) alcohol comes out. If I were printing a ton, I would simply have 2 or more of these so I could continually rotate batches and keep printing.

I by no means print on the level you do, but I have adapted a method where I have a bucket of “dirty” IPA that I do an initial rinse in. After that I clean it in the wash and cure station with my “clean” IPA. I let the dirty bucket sit ( I use a clear large container) and the resin will eventually settle. I then put that bucket into a large container with a UV light and let it cure for quite a long time. The resin then becomes cured into particles that you can filter. If you have too much resin in it, it will become like gel!

I've been using a degreaser (Spray-9) instead of IPA, but Coffee filters have been working well. You need something in the funnel to keep the filter off the walls or you just get liquid filtering though the bottom and not the sides. I use a webbed insert I printed. as the filter starts to clog with resin the flow rate slows so I end up with the funnel full and draining slowly, But I just let it sit for a few hrs and et eventually drains leaving the a thick paste of resin in the filter. Curing outside dries it out. But I'm only doing about 1L at a time so you may need multiple funnels to do 8Ls My fluid isn't perfectly clear when done though, but pretty close. To get back to 100% distilling is probably your best bet, all be it dangerous. You could try a wine filter pump. They work by using a pump to push the wine though multiple very fine filters under pressure to remove very small particles. You would still need to pre filter somehow though to remove the majority of the resin. Example of a wine filter kzfaq.info/get/bejne/oMufm7Sg2NSXZIE.html

Set up some sort of centrifuge? Like what we use in the lab to separate liquids and suspended solids in liquids? But never tried to separate the volume you would need.

I have only been printing since January, and no where near as much as you, but I found that if I left the ipa on the windowsill in an enclosed container I got some good results. Still got the sludgy bit, but I think because it was a much slower cure most of that settled to the bottom so I could pour off maybe 75-80% of clean ipa before getting to the sludge.

Have this same problem, what I've been doing is reusing those big Gold Peak tea bottles and pouring my used IPA in there and then sitting it outside on the side of the house for a few days. That same gelatin blob will form but it tends to rise to the top of the container and the IPA settles to the bottom and isn't entirely clear but significantly clearer than it was before. The hard part is trying to filter it out from that blob as the blob tends to quickly clog the opening of the bottle and it's hard to separate it without making a huge mess. I try and filter it out with a paper strainer and pouring the contents into a disposable aluminum pan and then dumping that back into a container to refilter again and then reuse. I've been able to reuse at least some of this IPA and haven't noticed any huge issues with it so far but it is a giant pain in the ass trying to filter it back out without getting that blob stuff everywhere.

Thanks for heading the charge on this! We're keeping the IPA business in business that's for sure. Here's to hoping the water washable resins will get better.

Just drop a slice of lemon and a little umbrella on it! 😂

Jessy, I saw the video from VOG (vegoilguy) that shows a way if doing it. I believe you are close to what he says but I think his secret is the time frame and how he lets it sit down. Hope it helps!

Me being one of those who suggested curing the resin in the IPA, i also say patience, let it settle, or if you wanna have some fun design an excenter separator or just get a salad spinner and put the container in it, should get them separated pretty quickly

My process involves more IPA initially but I think you can use it longer. I will use a batch, wash my prints in it, wait for it to start turning colors. Once it is noticeably different in color (a few washes) I will pour it back into into the IPA bottle, let it sit for a while to let it settle out some then blast it with UV. After it has settled and the UV made the sludge I decant the remaining back into another empty container. It is admittedly a lossy process, you lose maybe 10-20%, at least the way I do it. You might be able to get a bit more if you filter the sludge.

Thank you for doing the research to begin with, seriously appreciated! Followed!

Something I discovered by accident - because the Anycubic Wash and Cure powers on into the "Cure" state I sometimes accidentally cure models I intend to wash. Well, I came back from the weekend on a Monday and had some prints to wash. The IPA had settled - it's not perfectly clear by any measure, but it's also not completely cloudy. I accidentally started the wash and cure on cure mode, and the gelatin stuff formed in the bottom, and in sheets along the side. Naturally, I had to clean this out. I filtered it through regular resin paper filters and ended up with not perfectly clear IPA, but definitely clearer. The gelatin sheets got caught up in the filter, and the goo at the bottom I DID NOT try to filter, but instead decanted into an empty water bottle and placed outside in the sun to fully cure and ultimately dispose of. Naturally there's some IPA caught up in the gelatin but without a more complex burn/vapor/capture apparatus I don't expect to ever be able to recover that IPA. (I assume alcohol creates a chemical bond with the resin which is why it is an effective cleaner. It can't really be filtered, because it's not flee floating particulate in the IPA.) So if you decant everything into a separate container - larger is better, the exact same size as the wash and cure basin would be best - and just let it settle, this lazy man method might just work.

I have a 8000ml container (looks like the new wash and cure + container). I put the container in the sun for a day and it gets the gel-goo stuff. I have 2 large totes and drilled 1/2" holes in the bottom of one. I set it up on wooden scrap blocks in the first tote. I put two layers of paper towels in it and pour in the gunk. The liquid runs through and the gunk doesn't. I take the gunk and put on an old cookie sheet in the sun. The resulting liquid does seem to clean well, but it is still grey. I figure it is just the pigment not getting filtered out. Not a perfect solution, but I get to re-use the liquid. This is just my main/rough cleaning. I also put the parts in my small wash and cure for a final rinse, which I keep with clean isopropyl and pour it into the big container if it gets too dirty looking. I am sure I do not use it on the scale you do and with isopropyl getting cheaper, I may just let it all evaporate in the sun and refill each month or two. Generally using sirayatech grey + tenacious for resin.

Distillation would be the correct way but you could also try getting it to seperate on its own. I know you said you're impatient and don't want to wait for it but you should be able to put it in a fridge to help speed up the seperation process. Might speed it up dramatically. Might be worth a try.

VOG has one of the videos on this subject go watch his

I got my anycubic mono se 6 weeks ago and have already done 250+ hours of printing. This here has been the bane of it all and I'm also impatient to let it sit for days. I have to turnaround prints to sell so don't have time to leave it to settle for a week! I have two buckets of IPA, a dirty first wash bucket that I dunk the prints in to wash most off the resin, before putting them in my wash station for a final clean. This saves my wash station IPA making it last longer. The buckets in between prints sit in my window to promote the resin to cure and after a week of daily use and some settling in between prints they're still cloudy and that never changes.ones intendedusually a ball of sludge at the bottom which I clean out and then filter the IPA back into the container. It will never be clear again but it is more transparent and cleans pretty well. How long were you UV curing the IPA, I literally out my bucket in for 30 mins in the curing station and nothing changed in the liquid. I don't know if the anycubic buckets have some UV protection because even in the window sill they still take a lot longer to cure any resin than similar sized air sealed buckets. I did as an experiment leave a bucket to settle in the sun. It took 9 days to go clear in the English sun! I figure as long as it is transparent and not opaque it is good enough. I don';t think distillation would be worth it, but I'd love to see a video that proves me wrong!

You may want to try simple evaporation: Pour your dirty IPA in a larger container. Place a smaller empty container (you may need to weigh it down so it doesn't float) in the middle of the pool of IPA in the larger container. Cover the top of the larger container with saran wrap. Place a small weight (a small rock?) on top of the saran wrap in the middle, above the small empty container. The dirty IPA will evaporate onto the saran wrap, condense, and drip into the smaller empty container, leaving clean IPA in the smaller container. This is actually a military survival technique to purify water.

Separation is whats worked best for me. You bypass the slowness of the process using multiple batches of IPA, this also helps avoiding it becoming too saturated with resin.

What about a sealed container in UV/sun? Would it prevent IPA evaporation yet still let the resin cure?

When I cured my IPA and got the gelatine type substance that’s when I let it sit fir a few days and the ipa just came right out of the jello and I “filtered” it in to a different container

I just did this and had decent results. Bit of a process though: I took a black light and shocked my tub for about 1.5 min, then did a rough filter through cheese cloth for larger particulate filter, shocked the IPA again and repeated the filter with cheese cloth, then did a 3rd filter with a fine resin filter but it got plugged up. It seems like the best course of action is apply black light till you get some clumps/cloudy appearance and filter as many times as it takes. I noticed a significant color shift in the IPA after doing this.

My use is only average but I clean my IPA by sunlight. Here in the UK our milk comes in frosted plastic bottles so I pour my dirty IPA into it while using old tights to catch any larger particles, leave in sunlight for about a week. Gravity seems to sink the resin to the bottom and then I pour back into a container when it is clear again, also filtering through some sheer mesh tights. Seems to work pretty well and I am still using the same gallon of IPA I bought with my Photon Mono.

A cheap, passive way to do this, and really the only efficient way, is low-heat distillation. Normally any distillation is fairly labor intensive or at least absorbs a lot of time babysitting equipment, however, you can use a heating pad designed for keeping reptile tanks warm, set it up inside a box and use the passive system of a container with fitted tubing (chemical resistance is a plus so don't use latex) and an assortment of fittings you can nab in the plumbing aisle. The box maintains the heat in as small an area as possible, the heat helps the alcohol evaporate (ideally above 140*F), and as long as you just leave it plugged in, you can let this go a few days and all that will be left in your base container is resin residue, water and miscellaneous junk that fell in your IPA. This does require you have a few gallons at your disposal and keep it in rotation. I've used this for years for other purposes but it works well. Two 5 gallon buckets with lids, a few barbed hose fittings and some tubing (and the heating pad of course), you're good to go. If you can't find or don't have a spare box that's large enough, the home improvement place will have appliance boxes for free you can cut down.

When I do the coffee filter method I do it after every print or every other print and I cure the fluid in clear water bottles (16.9 fluid ounces if I remember the size right) before filtering. Still turns out a little murky but much cleaner than before and I have to change filters every bottle because they will get too clogged after that. It's not a fast process unfortunately but it has worked for me so far. I prefer not to wait typically because clean alcohol really makes a difference in my prints, but I do wish there were an easier way to do it in bulk like you seem to want to do. Interesting idea for distilling the alcohol, but I would want to avoid that setup as well, especially considering the flammable nature of alcohol. I wonder how much the container may play into things. Probably not much if any since I know PET tends to be chemically resistant, but it does leech chemicals into water and possibly moreso into alcohol? I haven't tried any other materials like glass. I think I'll see if attaching a bottle brush to a drill can quickly clean the left over residue of resin left in a Mason jar or something. Edit: I just remembered that there's an old survival method of distilling water where you take a basin/tub of salt water (resin alcohol in this case) and put a piece of plastic over the top and a rock in the middle to create a low divot point (kinda like a funnel) and a container inside the basin. Basically the sun heats the water into vapor, the vapor gets caught and collects on the plastic and as it collects and cools it gets larger and heavier to the point where it will be pulled by gravity down to the point where the rock divot is in the plastic where it drips down into the catching container. This would probably be too slow of a process for our needs, but it would be interesting if it worked in some sort of sealed container and maybe using a sun oven to speed things up. Perhaps having some sort of heatsink system for the collector container to keep the collected fluid cold.

2:00 I'm sure you figured this out by now seeing the date but this has to do with resin composition and saturation. There's a tipping point when your IPA is so saturation with resin from lack of cleaning, the chemical reaction yields that gelatinous result. However, if you keep it relatively clean and let it fully settle for atleast a day, you'll be successful recovering a fair amount.

This has been covered by Vog... he's nailed it

So i tried the precipitation method and it actually worked. Bear in mind that my volume of printing is not massive at all (possibly a liter of resin a week). i have a big glass jar where i pour roughly filtered IPA and leave it to sit in front of a window for days. After roughly 4 days the liquid is fully separated in two phases. The only other method i can think of is spinning while curing but that would require fairly expensive machines

So a couple of things - firstly, search VOG's channel - he was able to post a guide on semi-successfully clean the resin. my takeaway from what's happening here is that you're waiting too long to clean it. It should still be translucent at worst, transparent at best. You should still be able to see objects through the other side. Then, just cure the ISO and filter it out. Secondly, you had the right idea with the Brita filter. I think that's the only thing VOG was missing as the final step. But don't waste your money on a brita. It's just a really expensive container with ion exchange resin and activated carbon. You don't really need the ion exchange resin, and activated carbon can be bought at a pet store in the aquarium section for super cheap. If you can find an STL for the plastic casing of one of those brita filters that'd be dope edit - ion exchange resin, not sodium silicate

I do not wait nearly so long, but my experience has been that the resins I used seem to start to fog it a little bit after a dozen or so prints. then I let it settle out in a jar thats not part of my washing stuff off operation. whatever settles out goes straight into a container that will be exposed to sun at the end, but the rest I put in the sun in a glass jar for like 15 minutes or so. the actual resin that cures will drop out of solution better when its more dilute to begin with I think. I shake it up to get goop off the sides and let that sit to settle for a day or more, pour it through a filter (cheap metal mesh not a disposable fine one like those paper ones) and the trick of course is to pour off only the almost or completely clear solvent at the top. Admittedly I started using denatured alcohol early on, so my solvent jars probably contain a bit of ipa but mostly denatured alcohol, and maybe it drops out of solution easier? I basically only lose solvent to what is absorbed by paper towels, what is trapped in all the stuff that settles out and eventually gets sun cured in a final step, or to evaporation from containers and spills. I have barely touched to gallon of solvent I started with, because reusing it with this settle out and half cure to precipitate it out of solution process on the initial 750ml or so, which I filtered twice or thrice in 2 months, and is currently clear enough to not tint totally clear parts when it looks clear. in my experience even solvent that looks clean might have enough resin in it to cure for a bit in the sun and separate, I am just way to lazy to do it like every other print. I suspect it would work though.

I must state that I've not started using IPA yet, BUT what I noticed is that after leaving my cleaning fluids sit for some days, all the resin that is suspended starts settling in the bottom of the container. At this stage, I usually put them in direct sunlight for a while so all the gunk in the bottom cures. after that, I run it through standard 10nm paper filters (as the one used to pour resin back in its bottle). The result is not perfectly crystal clear, but it's way less cloudy and residues are not left on the printed models. As of now, what I'm using to clean my prints is: 90% Denaturated Alchol (leaving it into direct sunlight destroys the pink pigment and avoids prints staining) Commercial Degreaser (in Italy it's called Chanteclaire) Tap water What I noticed is that resin tends to set better in the tap water container than the other two, so maybe alchol and degreaser are preventing resin from clogging. I'll take this chance, since you use Elegoo Mercury to cure loot studios prints, how long do you let them cook under UV light? I print 32mm scale models and I get the best results usually between 10/15 minutes, but people are saying this is way more than needed. I use Elegoo ABS-Like grey resin. Thanks for your content, man

Im about to do some tests with this as well. What I have come up with is simply putting the dirty stuff in to a large container then letting it sit and separate. The solids go to the bottom and the rest goes through out. I am then going to use a large sponge to soak up the liquid and hope the solids stay at the bottom. The sponge contents can then be strained in to a filter like that Brita that you had. the solids will then be cured and thrown away. And hopefully I have some clearish reusable IPA.

Curing the ipa actually does work. The reason it's not working for you is you're not letting it settle before curing it. That makes the resin form it's polymer chains and cross links with heaps of isopropyl alcohol trapped in a matrix. Personally I let it sit for a week for some of the longer settling resin and two weeks for this really cheap anycubic resin I have. If you can't let it sit you may not have an option here, this is the main way we clean water it in massive settling pools. We do this because it is one of the best and cheapest methods we have. I'd highly recommend you get yourself a big bucket and buy more ipa. When it's saturated, pour it into the big bucket and leave it for a week, two if you can, then use that new ipa you have. Once the old ipa has settled out, give it a good curing then filter through a coffee filter. Bam cleaner ipa, you need two or maybe more 'sets' of ipa because it neeeeeds to settle. I use a 7L resin wash for my primary dirty wash then 3L for my clean, and my clean wash looks brand new after hundreds of hours. Probably because I regularly settle, cure, and filter my big wash, about once every two months. The amount of resin you wash in also obviously helps to keep it usable for longer. I'm not sure which specific resin you're using, but you can lookup the sds for it and find out what the primary monomer being used is. Then the navier stokes settling equation can tell you exactly how long you need to let your resin sit. Although keep in mind the particle size is likely one monomer long, hence the settling time of weeks. Good luck but patience is the best thing to clean your resin with, but I get that might not work for you and your busy schedule

having been dumb with my first printer i ran into the gelatine problem, i found an effective way to reclaim a bit of ipa was to simply put the gelatine in a tupperware box, with gelatine resin in one corner and raise the corner below the resin, leave in direct sunlight and as the resin cures more the ipa leaks out, its more or less a resin foam thats left over so if it gets to such a consistency you can literally squeeze out ipa, which i did with a bit of flat scrap plastic. granted i reclaimed a fraction of what i put in but i lost a good chunk to evaporation. i was using the same ipa for several months because i didnt know i should filter it

I have a process that works relatively well. Good enough to get clean IPA for washing prints. I pour the dirty IPA into a 3 LT plastic milk bottle (clean it first) and let it sit outside in the sun for about 2 hours or until the liquid turns milky white but, but not long enough for it to gel. I then use a fully unfolded paper napkin in a large funnel to filter this into another milk container. It is a slow filtering process and I usually let it filter overnight. If the collected IPA still looks a little cloudy I put it back out in the sun again and repeat the filtering process. I find that I only need to do this once or twice as I don’t let my IPA get too dirty. The recovery rate is around 60-70% but it is better than throwing it out. Oh I live in Australia so we have plenty of Sun to do the work. As I find the Wash and Cure to strong for the process.

Interested in your results. The problem - is that the solution - is the problem. The resin is partially dissolved (a solution), not just a particulate (mixture). So a filter will mostly only get out the oversaturated concentration of resin, and the alcohol will actively be trying to dissolve that through your filter. Chemistry has a general rule you can't filter to separate out a solution. You have to process it in some other way to either chemically change it or accentuate one of its properties in a way you can separate (eg freeze or evap temp, mass). Plus, these resins have dyes to color them. Dyes are designed to readily mix and dilute into things, so getting them out will be harder unless you can do something like a small enough filter (micron rating...) that you can pull out the micron level dye pigment molecules. *speaking from experience filtering oil, that will need pressure to force the liquid slowly through the filter and maybe need heat to speed it to something only slightly above a glacial pace. ***You wanted to avoid distillation, but honestly, the task you are asking for is the exactly the kind thing distilling methods are best at.*** Keep easy to evaporate alcohol, non-evaporating sludge behind. *Instead of heat, try freezing then using a filter? The alcohol should stay liquid, so you might get a resin slushy that would filter out as particulate. . On other methods: For the slow settling method: you don't need patience, you just need several containers! (and you want them Now! : ) *the deeper the better. *While you are using 1, the others get weeks to settle. *With several, you don't have to worry about accidentally bumping and stirring up 1 batch. *Better still, you can take the cleanest portions off the tops into 1 container for immediate use again, mids into another to settle again into mostly clear, and murk into a last container. Just let the murk settle for extra long, get the tiny bit off the top and gel the rest of it. Filters: on the paper filter routes, it won't get anything dissolved. To get a small enough micron rating to pull the dissolved stuff, you would need pressure/vacuum differential, which a paper filter can't handle. -A metal filter system isn't cheap and is a lot of work to clean out when it near instantly clogs filtering ~10micron particles (which may not be enough for this). -A vacuum pump would evaporate all your ipa into a massive air volume. Not a good method, when what you want to keep is the ipa. A centrifuge is an appropriate separation method, but they can be very expensive, and we don't want to spend more than the ipa is worth trying to recover it and have a high maintenance machine to take care of. I'm going to look at comments and other videos and see if anyone has a good solution.

I havent' really been doing this long enough, but in anticipation of this, I also have a first pre-wash contaniner with my most dirty ipa, before it goes into washing station, so that I have smaller volume of the dirty ipa, and my bigger volume in the washing station should last longer and yes, when I will deal with the diry ipa, my plan is to put that into a see through bottle and let it sit on the window for a day, so that it cures more slowly , letting some of the resin separate and then filter through something - maybe coffee filter - to get it back into the game

I seen on one guys channel had the same problem with the gel like consistency. Used a package of cheesecloth, using the full thickness as it came in the package, he placed a section in a large funnel and poured the thick ipa into the cheesecloth lined funnel. fairly clear IPA came out leaving the gel. He then did like chessemakers do and slowly twisted the cheesscloth down tight around the gel. He was able to recover a lot more IPA. What he had left in the cheesecloth was just like a hard crumbly cheese mixture.

Hey I have a Prusa SL1 and cleaning station too, working with resin is messy and costly on the IPA side things and there is no way out of it! its just part of the process. Getting rid of the IPA that has resin in it is another problem, I pour my IPA in trays leaving in the sun to dry and go hard and what's left I burn in my fire pit! cheers mate

Personally, for my big ultrasonic, I designed a little cage that uses 1 or 5 micron home water filters cut into thirds, and a cheap aquarium pump. Don't ever let the tank get super dirty, it is an active filter system running anytime I clean anything. It legit pulls like 99% of the schmutz out of the tank easily. Those filters get GROSS after a while, but the mean green / ipa mix stays perfectly clean for ages.

Just buy a water distiller, that's what I do and it works phenomenal!

What I've done and it gets the used denatured ethanol back to crystal clear: Pour the murky stuff into a container and set it aside for weeks. Like two weeks minimum, with no touching, bumping or jostling the container. The taller the container, the better this works. What you get is all the resin accumulating at the bottom in a murky sediment, then you can simply pour out about 90% of it. The muck at the bottom is not hardened, it's not that gel like stuff you got, so you gotta stop pouring once you see the resin start to get mixed in with the clear ethanol. I'm guessing it just separates from the alcohol because of gravity and the resin being bigger molecules. With this I can pretty much reuse the stuff I wash with as many times as I want: Rotate the used stuff into bottles, pour out a cleared bottle into the cleaner, top off with new stuff. I don't know if this works for IPAs, but it might we worth a shot to pour a plastic bottle full of the murky stuff and set it into a corner by itself and see if that works for you.

my process is great and works for me. I filter the ipa through a paint filter into a glass container and let it sit outside in the sun for a day or 2. and then i take that and run it through a paint filter again and its clean IPA. albeit its a little yellow, but still transparent. whatever solid resin that is left over from that i will let cure under the sun and then toss. i then use that sun cured ipa as my first wash and put fresh ipa for my second. this whole process gets a lot of extra life out of the hard to find ipa.

I am certainly not a chemist and I haven't actually started 3d printing yet. I am still learning before I am buying. But I did look into the filtration process for water and discovered that their is commonly a phase of the process where coagulants such as Aluminium sulfate is added that rapidly combines with particle that are suspended in the water and cause them to separate. Perhaps this could be a solution you could try?

If you want easy testing samples wouldn't it be possible to just mix the isopropyl with a bit of resin directly from the bottle?

Did you consider using something like those oil absorption wipes? I'm not sure those will work in this instance but there may be a fabric type filter that reacts/binds with the resins and not with IPA. That is how those oil filters/wipes work, they attract and bind with the oil but water is unaffected

I run multiple settling bottles to settle out the resin and ipa... I don't let the ipa get that dirty to start with in my pre wash and change it out as soon as the ipa gets cloudy... this goes into bottle 1 to settle... what was already in bottle 1 goes into bottle 2 for further settlement... what was in bottle 2 goes into bottle 3 for further settlement and what was in bottle 3 becomes my new prewash. I use the fresh unrecycled stuff for my final wash. I figured having multiple stages of settlement meant I could be constantly recycling which was quicker than waiting for one bottle of ipa to settle out. It isn't as clear as straight ipa, I think this is just some of the pigments from the resin still in the ipa. Works for me but I don't print every single day but still multiple times per week.

I clean mine a bit more regularly to avoid ao much build up. It gets poured into an airtight clear container, put in the sun for 1-2 days, shaking it up when it forms the large gelatinous white blob and leave it to sit once its in smaller chunks, wait another day or so in the sun and the IPA should be on top with a thick jelly on the bottom. Gently pour or siphon this into my two stage funnel ,smallish metal mesh at the start of the neck to grab the any big particles and midway down as it has an "extension" pipe you can attach i fold a thin porous fabric so it passes through 3 layers of it, This grabs any tiny particles as they will stick the cloth and pass through, mostly clear IPA at the end. If i'm still not happy, I will grab a fresh piece of fabric, and repeat the strain . I have 3-6 containers to cycle through, strain into etc. Sizes are 3x 2.0L and 3x 1.7L. The fabric i've been using is a disposable medical gown i just cut strips off. Its very thin, very tight weave but still tiny gaps in it. can fold it over as many times as you like to increase the filtration.

I do a double rinse, the first IPA gets most of the junk, as soon as I am finished with the IPA I put it in my curing station. The now cured resin particles setting out to the bottom in a few hours, while the IPA is curing the part goes into the washer to make sure there is no leftover resin. The wash tank really does not collect much residue, I do cure that IPA as well however it takes a long time to collect enough where it needs to be filtered. Your Jell-O is because of the amount of resin suspended in the alcohol, by curing after every cleaning the solids cure and drop out of solution which leaves you with larger easier to filter particles.

You could try using a Büchner funnel with a sintered, finely fritted glass disc. That has the potential to be fast and effective.

I don't print very much in resin. but i started to collect the dirty liquid in glass jars. since i am lazy they sat around a few days.it did start to separate. but i think it cures better in glass. it continued to separate during curing. I was previously using the same plastic containers i was using for actually washing the models in.

A user mentioned maybe a pool cleaning solution called Floccing. Which is used to push suspended particulate to the bottom of the pool for vacuuming. And of course last night I watched a video (and of course I can’t find it now) of a guy using a fish tank clarifier to settle the impurities(which worked faster than waiting days). I believe the active ingredient was an Aluminum Sulfide/Sulfate, you may have to look around. But Floccing should be available at all pool stores.

Your problem is patience :-) By sticking it in the curing chamber, you're basically curing the resin leftovers too fast, which is why you end up with a gooey mess. Filter it once into a seperate clear bottle, to get rid of any bigger chunks of cured resin. Then leave it in your window sill to absorb natural UV for a couple of weeks. This will cause cured resin to precipitate to the bottom, and leave a virtually clean IPA. When your IPA solution is clear, filter it through a regular coffee filter - pour slowly, as you don't want to stirr up the settled resin too much. You'll probably clog up a few filters in the process, but they're dirt cheap. Compared to boiling IPA in a still it's a much safer process. So if you keep a couple of IPA batches in circulation, you'll have a "fresh" batch by the time your IPA becomes really dirty.

Resin 3d printing newbie here : I'm thinking about getting a resin 3d printer but one thing I wonder about is how do you dispose of the resin residue when you let the isopropyl alcohol air dry? Can I just chuck it in the bin and call it a day or should I go to some institution specialized in chemicals disposal?

Considering the problems you face the issue might be trying to clean IPA after the "point of no return", maybe. What I do is pour IPA in a 5L transparent bottle and leave it outside for like 3 days and let resin both cure (as much it is possible in IPA) and gather on the bottom since it's heavier than IPA. After that I can use coffee filters and it works like a charm :). It seems you have much more resin in your IPA so maybe leave it still for a couple of days so that resin can separate from IPA before any UV exposition? Should be easier to deal with such residue.

Well, since this isn’t a mixture which separates easily because the resin is like an emulsion in the IPA, you’ll need some kind of ultra or nano filtration to separate this. Which of course is technical difficult and expensive. In this case a distiller is the easiest solution because the boiling point of IPA isn’t high. A bottle filled with your mixture putted in a pot with boiling water (Au bain Marie) will do the trick. Adding vacuum will lower the boiling point further and the pumped out fumes can be easily condensated in a hose which goes through a pot of cold water. So all you need is a steel bottle (strong), a hose capable of 100 deg Centigrade, a vacuum pump and another hose used to cool and condensate the IPA. On the other end, cleaning of the print before inserting it into the washer will of course help to minimize the need of this exercise.