FUD wax removal.

Discussion in 'Finishing Techniques' started by stop4stuff, Jun 3, 2011.

  1. stop4stuff
    stop4stuff Well-Known Member
    With the arrival of FUD and the ability to have very small clearances between moving parts in one print, to me one obvious application was an attempt at creating the worlds smallest working rubiks cube - the current record stands at 10mm, my cube is 6.2mm and printed in one hit :)

    3x3x3 Twisty Puzzle (aka Rubiks Cube)
    Large image here

    The spacing (as printed) between the parts is 0.1mm - the spaces are filled with the wax support material. Here's a few of the methods/products I have tried in an attempt to disolve out the wax and free up the parts.

    Hot water - the wax melted out, but some of the parts were fused and one part broke - I tried two cubes out using this method, the second broke too.

    Alcohol hand sanitiser - this product contains 62% ethanol and seemed to affect both the wax and plastic resulting in some parts stuck together, the central spindles gone soft and broken.

    Penetrating oil (WD40 etc) - partial success, but still one of the central spindles broke.

    Mineral/white spirit - disolves the wax ok, but also softens the plastic leading to breakage and failure.

    Ear Wax Remover - still soaking in this - the remover is quite a viscous fluid at room temperature, and thins qute readily with a bit of heat - this product may work out ok if the temperature can be kept 10-15 celcius above roome temperature (think body heat)

    Weak NaOH soultion (caustic soda/lye) - still soaking in this - again this is looking promising

    One of the main issues I have with the cubes are the spindles breaking - currently they are 0.7mm diameter - this maybe because I am not waiting long enough before attempting to move the parts.

    Feel free to add ideas, share attempts, sucesses & failures.

  2. virtox
    virtox Active Member Moderator
    I had great results with hot water and (mlid, the eco-stuff) dish soap. (and some patience ;) )

    I was able to clean out 0.3 mm through holes in a few mini-Menger cubes. As one can imagine, there is a LOT of support stuck in the holes, the bags were all greasy etc.

    I just put them in a jar with the water and soap, and stirred and shaked.
    You can see all the wax dissolve a float to the top. Rinse and repeat.

    After two runs the yellow was nearly gone and all holes were visible.

    While not as brittle as your designs, I can recommend it for cleaning holes.
  3. KoalaCreek
    KoalaCreek New Member
    I have had good success with Acetone, which was recommended by the guys at Fineline Prototyping (who also use materials by 3D-Systems).
    It does not seem to affect the FUD and resolves the wax. Just be careful with the stuff and use gloves.


    Last edited: Jun 3, 2011
  4. stop4stuff
    stop4stuff Well-Known Member
    Jeroen, thanks for the tip... I think I have some acetone in my garage - and my wife or daughter probably has some nail varnish remover (contains acetone). Also, it just sprung to mind acetone->acetic acid->vinegar - google results show vinegar can be used to dissolve wax :)

  5. LincolnK
    LincolnK New Member
    Have you tried hydrogen peroxide?

    Also, I am curious, with the acetone, do you just soak the object in it, or use a q-tip to just wipe away the parts that have the wax?

    If you soak it, how long do you soak it for?
  6. KoalaCreek
    KoalaCreek New Member
    I do not soak the object in acetone, I just use a q-tip and a brush.


  7. tebee
    tebee Well-Known Member
    Going back to the original post why should hot water cause any problems ? Fud is a plastic and should not be affected by water. The only reason I can think of is that it was not properly cured in the first place.

    I've had items in it sitting in near boiling water for 40 mins at a time without problems while I've been dyeing it.

  8. stop4stuff
    stop4stuff Well-Known Member
    FUD is acrylic with a softening point lower than boiling water temperature - I think my little cubes failed because the internal parts became deformed and when I tried to move the pieces, they broke... the cubes really are tiny and the wax inside is 0.1mm thick, so surface tension between water & wax is at play too.

    I popped a cube in a jar of just boiled water and microwaved it, keeping the water boilng for 5 minutes - after cooling some parts are still solidly joined by wax, and the plastic has gone from transparent to a milky white.

    Of all of the things I've tried so far, ear wax remover is ahead, but it does need to be kept at a constsant temperature to thin enough to work on the wax, and yes it has been days now that one cube has been in the remover.

    Diluted household amonia solution didn't do much.

    I still have yet to try acetone/nail varnish remover.

    Last edited: Jun 9, 2011
  9. tebee
    tebee Well-Known Member
    Ah OK I've always kept my water just below boiling point , I've noticed even WSF gets quite soft as at that point.

    Have you tried mechanical means, like an ultrasonic cleaner? I've got one and find it wonderful for crud out of places you can't easily get to. Look for a friendly dental lab or jeweler near you as they almost certainly have one.
  10. KoalaCreek
    KoalaCreek New Member
    Just try the Acetone ... no need to soak it for days ... :D
  11. stop4stuff
    stop4stuff Well-Known Member
    I have one sitting in nail varnish remover right now (I couldn't find the pure acetone I thought I had in my garage)

    Will see how it goes.

  12. jasolo
    jasolo New Member
    I have tried nail varnish remover (with castor oil) diluted in water with my level-4 menger cube. I dipped it during a couple of hours, but only some superficial holes were cleaned.

    Now I'm trying again with Tetrachloroethylene (also called Perchloroethylene), used in dry cleaning of fabrics and to degrease metal parts. The first time I had previously dipped the model in dish soap, and only checked the cleanness of the holes when the model was wet, although I think this method didn't go deep. I'm saying all of this because after using Tetrachloroethylene, the holes seemed uncleaned when wet, but when dried the wax was missing (0.3mm holes). Now FUD looks white, but not transparent, although maybe the complexity of the Menger model makes difficult to see any transparency. I could check this with a simpler FD model that shows some transparency.

    Now for the second try I'm using the model used for the nail varmish remover test. I have also diluted the tetrachloroethylene in water, although this substance has low solubility and sinks to the bottom. In the first try I stirred the mix a couple of times during 2-3 hours. In this second try I've stirred once and I'll check the result after 8-10 hours (left at home).
  13. jasolo
    jasolo New Member
    Definitely, tetrachloroethylene removes the wax but it must be used purely or stirring when mixed with water, and in less than 1-2 hours. The problem is the material gets really "white frosted" once dried, as when very cold metal condenses the water vapour in air. I've tested that with a FD model and only the flattest surfaces doesn't get white (only in the printed lines) while curved surfaces get fully white as White Detail material got dyed with tea on curved surfaces.
  14. stop4stuff
    stop4stuff Well-Known Member
    Nail varnish remover claims a victim :(

    I kept checking a cube in the nail varnish remover, after 24 hours, there was still wax between about a 1/3rd of the parts, the last time I lifted the cube out, all the bits that were free of wax fell apart.

    Ear wax remover is still looking good, even though it is slow.

    SIXTHSCALE New Member
    has anyone tried Hydrogen Peroxide yet? None of my FUD models have wax on them, so i can't try it myself but i have more complex models coming and am curious if anyone has attempted it... i've noticed that it seems to work better than ear wax remover at removing earwax, and it is much thinner.
  16. ErkDemon
    ErkDemon New Member
    Peroxide: I've tried sitting a smelly yellow "waxy" FUD model in room-temperature peroxide for a couple of days, but it did nothing.

    Tried earwax remover (peanut oil with alcohol), and dunked the thing in hot water, the oil that came up to the surface was "yellowy", so some wax had been removed. After repeated dunking in boiling water, alcohol, peroxide and anything else I had to hand in various combinations, the holes in my weeny 4-G Menger sponge have opened up, but the crinkly fractal snowflake sponge is still very yellow. I'll have to give acetone a go.

    To be fair, the snowflake sponge is probably a worst-case scanario, the 3cm 4-Gen Menger sponge was pretty pale (just a little smelly), but the snowflake sponge was almost lemon-yellow. That was with about two hundred thousand faces, most at right-angles to their neighbours, and all sorts of voids with multiple pinhole openings, so the surface area and surface tension for coatings on it must be horrendous :D
    I'm sure that normal models are fine in FUD. Actually, I don't mind the smallest holes not all being totally clear (they're so small that it's difficult for people to tell), I'm more interested in getting rid of the colour and the odour with these "jaggy" fractal shapes.

    Sharpness and crispness of detail with FUD is really excellent, btw.
    SIXTHSCALE New Member
    so that wierd dill pickle smell isn't just my imagination? :laughing:
  18. jasolo
    jasolo New Member
    I had forgotten to post an image after the cleaning with tetrachloroethylene. As I said, the wax disappeared but the material got white on the surface (the holes are 0.3mm wide). The whitening isn't a problem in this model, so many small details makes difficult to see any transparency, but for other models will be surely a problem and tetrachloroethylene has been classified as probably carcinogenic to humans.

  19. jasolo
    jasolo New Member
    I have tried two new methods with a new Menger cube:

    - The first one is the slowest and consists of putting the FUD model over a paper on a warm ambient (over the router or through the warm air expelled by the computer's power supply fan). The liquified wax gets trapped on the paper, so it must be replaced by a new clean one periodically. After several hours only some clean holes were visible so this method requires a lot of time but is the less aggressive.

    - The second one is quicker and uses white spirit (Stoddard solvent), the solvent used in painting. All the holes got clean and the material didn't got white as happened with tetrachloroethylene, but I'm not sure if it affects in another way the surface of FUD/FD objects (no more FD models at hand). Could anyone test white spirit on flat and curved surfaces?.
  20. BillBedford
    BillBedford New Member
    The white stuff is actually part of the build. It happens when there is an interface between the plastic and the wax support material. See this photo http://www.shapeways.com/forum/index.php?t=getfile&id=89 44&private=0. You can see there is a little trail of white beneath each column of bolt heads where the was has supported the surface detail. Sometimes if you run your finger nail over the model surface you can feel that the white part is slightly raised.
    The only way I have found to deal with it is by abrasion, either with a glass brush or by burnishing the surface with a wooden stick.