So every couple months I clean my resin contaminated alcohol using alum powder (link to a video about the process)

After cleaning it I let it sit in the settling containers until I need to clean my alcohol again. At which point I swap the alcohol that was cleaned into my main wash and cure station tub and then put the dirty alcohol into the other tub I use exclusively for cleaning the alcohol.

Edit: For those curious I can share an image of what the alcohol looks like after it’s had 24 hours to settle in the settling containers.

  • dual_sport_dork 🐧🗡️English
    11•1 year ago

    Resin printing remains somewhat of a mystery to me since I don’t have a resin machine and nor does anyone I know. So it’s always neat to see these insights into parts of the process and work flow I’m not familiar with.

    • GormadtOPEnglish
      1•1 year ago

      That’s pretty much how it was with me until I ended up being the first of my friend group to get one

      It’s been an experience for sure but it’s been a welcome learning experience

      Though if you do get one someday be sure of one thing above all else, safety first. Never slack on safety because “oh how bad could it be?” The answer is really bad.

      Also you will use a crap ton of nitrile gloves. Like an absolutely comical amount.

    • GormadtOPEnglish
      5•1 year ago

      Usually I can see it start settling while it’s mixing but it doesn’t fully settle during mixing

      Usually I’ll be able to see a noticeable difference in 24 hours but I’m actually not fully sure

      If I don’t notice it settled enough within a couple weeks I’ll add a bit more concentrated alum solution to each settling container and shake the hell out of it

      But in general having one container worth of alcohol settling while the other one is able to use is a good idea because settling can take awhile if the alum solution isn’t very concentrated

      Edit: By concentrated alum solution I mean like 25 50 grams per 100ml of distilled water, it should fully dissolve before you add it to the alcohol.

      Edit 2: I double checked my notes, it’s actually 50g per 100ml. It helps to mix it of the water is warm (NOT BOILING!!! ONLY HEAT THE WATER!!! And have it just warm enough to dissolve the alum. Then wait for it to cool down a lot, like barely warm.)

  • @KyvalEnglish
    3•1 year ago

    Can’t watch the video at work, but I suspect the video is about coagualtion & flocculation. The resin is coagulated from disolved resin particles into suspended resin-alum complex particles too heavy to remain suspended in solution, which is why a small-scale settling pond works.

    It’d might be a bit quicker/easier to put it through a filter or series of paper filters. Nothing crazy. Even a coffee filter should get most of it. Micron scale filters aren’t terribly expensive but clog quickly, so it’s best to run a coarser filter to get most of the big chucks first. Granted, not sure how long the coagulation process takes versus the flocculation process. If the coagualtion process is slow but the flocculation process is fast, filters probably won’t save much time. Though they may make cleanup easier.

    Eventually, the IPA will be diluted with water from the aqueous alum solution (I assume he’s using an aqueous solution as alum is barely to not alchohol soluable). There’s the salt trick to separate the azeotrope, but I haven’t personally tried it.

    Lots of work, but still better than those guys who distill the dirty IPA with non-explosion proof apparatuses. shudders in OSHA

    • GormadtOPEnglish
      2•1 year ago

      You’re right about what it talks about

      Eventually it will dilute too much to be effective for resin but that will take awhile I think

      Personally I use about 25ml (it’s more concentrated than in the video) per liter (I do 4L at a time) so it will take a long time to get too dilute as I started with 95% alcohol (I’ve heard of people going as low as 70% and still being fine for cleaning resin prints)

      Those people I see distilling IPA with nowhere near a proper safety setup makes me sweat for sure. I’ve distilled a lot of alcohol (not for resin, for other reasons) and it can quickly go to shit without specific levels of control. And you need to have a lot of safety procedures in place just in case.

      If I was to distill my resin contaminated alcohol I’d try to purify it as much as possible before distilling to bring it closer to known variables for me. But it will be awhile before I do that as the gear I’d use for it would be dedicated to that purpose specifically from that point onward.

      Also I use just ethanol as I have an easier time getting my hands on it in large quantities, it works great for resin as well and it’s not as gnarly as IPA.

  • @[email protected]English
    2•1 year ago

    How many prints do you think you’re putting through before you’re cleaning it.

    I run mine through a porous rock filter (I’ll try to find the video link) every couple of months.

    Typically I pre wash with Mean Green, then into the isopropyl which helps extend the life of the isopropyl.

    • GormadtOPEnglish
      3•1 year ago

      No idea unfortunately, I typically only print a few build plates of models a week and then it’s a few months between cleanings like this