Fud Has White Areas/white Powder/sparkles On It After Uv Curing+cleaning

Discussion in 'Finishing Techniques' started by BraselC5048, Jun 11, 2018.

  1. BraselC5048
    BraselC5048 Member
    I got a bunch of FUD models, and now I've got a bunch of strange problems. Many of them have white patches on them (but only on their sides/under overhangs), and under overhangs the entire surface is often white. It doesn't come off under heavy scraping with a fingernail. It may or may not come off with vegetable oil. Water, Dawn and a toothbrush do nothing. There's also a strange white chalk-like substance accumulating and completely filling in various deeply recessed areas, which will come off easily by a fingernail or hobby knife (or anything else - but not remotely all at once, and it's practically impossible to get it all from even a small area). (It's a bunch of powdery-stuff that only sticks to anything just well enough to avoid falling off.) It does not seem to dissolve in water or vegetable oil.There's also a bunch of tiny sparkly/shiny spots in various recessed (or even just hard to get to) areas, which no NOT come off with Dawn/water and a toothbrush. One of them also acquired a "fringe" of around the edge (only) of the bottom, very brittle and comes off if scraped far less than what would damage the FUD.

    The powder completely fills many crevices, and I don't like the idea of trying to clean them all out. On top of that, one of them has gigantic recessed areas along the sides entirely sparkly. Here's the thing - I got them just 6 days ago! All they've been exposed to is UV light (intense sunlight outside, actually) and tap water with Dawn mixed in. (Just squired into the water, not a dilution, far less concentrated.) All of them also showed up right out of their bag extremely sticky. As in "brushed oil on half an hour ago and didn't do any cleaning whatsoever" sticky.



    For perpetration, I followed the advice I'd read and gave them some UV curing. Method was in direct sunlight on white paper for likely several hours total. They hadn't been cleaned yet. Oddly there were greasy "wet spots" on the paper around the models, the amount of which completely correlated with how stick they were when they showed up, and had a tendency to decrease in size at the next UV curing. (They were cured in multiple sessions outside, maybe 7-8 hours total, noon-3pm, 95 deg F temperature.) After the last curing they were rinsed under water, then soaked for 2 hours in dawn and water (heavy squirts of Dawn into water, not anything close to "poured out of the bottle diluted X"), then rinsed them under the faucet. From there they were soaked in plain water for a few hours, then allowed to air dry on the counter, away from windows.

    And now I've got this problem. I have not put ANY paint (or anything else) on them, only water with some Dawn in it. I'm leaning toward it being simply a lot of bad plastic, and just getting replacements from customer service. (They shouldn't show up anywhere near that sticky, and again, I've only had them 6 days.) This is all just completely bizarre, three different problems together and quite severe too, and I don't particularly like the idea of figuring out how the heck to fix them. Cleaning some frost off I can understand, but with every known problem at the same time and quite severe, having gotten them a few days ago?
     
    Last edited: Jun 11, 2018
  2. Model_Monkey
    Model_Monkey Well-Known Member
    The characteristics you have described are not normal. There may be different problems at work here affecting your models. Recommend contacting customer service at your earliest convenience.

    Provide photos, if possible, and order numbers. The order numbers will help SW investigate what went wrong. The order numbers will give SW the information they need to determine from which factory the parts were printed (or outsourced), when they were printed, help identify the batch of resin, and from which machine(s) the parts were printed.

    Your description of "a strange white chalk-like substance accumulating and completely filling in various deeply recessed areas" is similar to a known crystallization problem affecting some models. That problem is being investigated by SW and the maker of the resin, 3D Systems (3DS). What is different about your experience is that the known crystallization problem being investigated typically takes much longer than 6 days to manifest. None of my customers (350-500 sales per month) have reported that problem since late 2016 but others may still be experiencing it. Since your models have developed the chalk-like substance so quickly, perhaps you are experiencing a different kind of problem.

    Purely speculating, it sounds like your models were printed with a bad batch of resin.