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    About

    Valide CSS!
  • Before building a DLP (bottom-up) printer, you'll need some idea's about the material properties. The main question is about:

  • Build platform: (non-transparent &) sticking qualities
  • Vat floor: transparent & none-sticking qualities

    I did some quick tests, for getting an idea about the adhesive & cohesive properties of the MakerJuice (green) resin. So I put about 3 drops of resin on different materials, lying around & shine with white light on those materials.

    Conclusion potential materials:
  • Build platform: Stainless steel (#14) is the best, others: PCB, aluminium, sandblasted aluminium, glass
  • Vat floor: PS, PMMA


  • During testing, the build platform made of stainless steel is working very well. After a good build, you could easialy remove the print, by cutting it with a (sharp) thin knife from the build platform.


    I like glass above PS, because I expect better flatness & transperancy. But glass without any top coating will NOT work.
    There are different options:
    Test:Materials:Tested:Remarks:Where to buy:
    AGlassQuick testThis is good build platform material, w/o coating not for vat floor.
  • Standard float glass could be found @ glass shop
  • or try (cheap) picture-frame glass
  • BGlass + HDPE-spray#1 & #2Maybe I used a wrong process or wrong type (PTFE-spary instead?), but it doesn't work for me.
  • PS (PolyStyreen) or HobbyGlass @ Hornbach
  • HDPE-spray: no idea where it came from
  • CPS (no coating)#3Working, but realy need somekind of tilting system, because the resin will very easialy stick to the PS. It gets loose by some very hard 'bang' sounds..(HornBach)
    DPS + Teflon/FEP foilSee tripple vat sectionLittle less transparent, but working.
  • muve3d.net adhesive sheets $3.50 per sheet: 8.5"x6.75"
  • read the FEP handbook
  • mcmasters.com Impact-Resistant Slippery FEP (cheapest?)
  • cshyde.com (expensive)
  • polyfluor.nl minimum size 2000x1220mm, thickness: 0.05mm: e35/m,
  • kastilo.de
  • EPS + Sylgard 184See tripple vat sectionIs working best (?), but it doesn't last for long..
  • ebay.com $49 per half liter
  • FPC + Generic Sylgard SubstituteTested by: JonSeems to work
  • ML Solar Generic Sylgard Substitute $37/lb
  • GGlass + Solaris Silicone Pint KitNot tested myself?
  • SSC $75/2.1lb
  • HGorilla GlassNot tested myself?
  • mcmaster.com
  • IPMP Not tested myself ?
  • mitsuichemicals.com
  • JSolar acrylic + Sil-Gel612 Tested by: RapApp Seems to work
  • home page
  • 2mm Acrylic plate is very flexible
  • Sil-Gel: different mixing = harder top coating
  • KFEP foil (50[um])#90 etcWorks great! Here a list of suppliers.
    L
    M
    N
    If you have test different (working) configurations, please let me know!


    Before testing the glass, first having a ground layer of PS & dividing it into 3 sections. I'm currently in favor of PS, because I have a lot lying around. The tripple vat consist of:

  • Only PS (again)
  • PS + FEP/Teflon adhesive tape (mUVe)
  • PS + Sylgard (about 1.5 mm thickness) (eBay)

    The aim for this test, was to test those tripple sections in one go, so all printing settings & resin temperature will be the same.

  • Testing #4 - #9.

    Learnings:
  • All 3 VAT-floors will work: PS; Teflon; Sylgard.
  • PS is sticking a lot. Never completed a complete build sofar.
  • Teflon-tape: works fine, easy to damage & a little less transparant.
  • Sylgard: defently best option. No sticking. But attracting dust & unhandy to create.
  • First layer height: very important.
  • Build platform / vat floor parallelism: also important.
  • Looking #4 & #6: same results. (6s exposure could be minimum w/o tilting?)


  • Trying different parameters and experiment with different resin.

  • Testing #10 - #25: FunToDo red resin
  • Testing #26 - #28c: MakerJuice green again

    Learnings:

  • Time for a new vat-floor: stiched a knife through the Sylgard, while peeling of a flat yoda piece (damn-it).
  • #29a&b: These builds realy sucks. Because of the broken Sylgard, resin is able to get between the PS&Sylgard and gets solid. It's also partly attached to the model, which is still moving up.
  • Flatness of building area and vat is important.
  • Start building height is important.
  • Don't 'expose too long' on one shot. This will 'burn' into the Sylgard.
  • Never ever put warm water on top of Sylgard! (Air will expands & lift the Sylgard from the VAT.)
  • Never use knife again, to get flat-build out of Sylgard. Once broken, the vat is gone.
  • Never disturb the resin during building! Also small amount of resin movement, will destroy the weak new build.
  • Tilting is not necessarly necessary…
  • Never clean PS vat with water and/or spirit (?) (espacialy with some leftover resin). Somekind of chemical reaction is going on. It doesn't seem this affects teflon/sylgard. But PS is completely gone.

    On the left, some resin below the Silgard is shown. On the right, a 'cleaned/damaged' PS section.

    Time for a new vat floor..


  • So, time for the real deal. This configuration with Sylgard on glass should work best.

  • #30 - #34: FunToDo red.
    Time for some new shapes to test:

    Then some frogs, which went great, so 4x6 frogs should also work, but it didn't, first the Z-shaft broke (it was not designed very ridgid), secondly there was not enough resin (oops) and with the third attempt...

    So the Sylgard was partly fogged (or frogged) & also damaged with tiny little holes somehow.. Overexposures gives worse effects. There were 'still' some clear spots, so tryed also the black resin. Actually none of these frogs came out nicely, because of the already damaged vat floor..

  • #35 - #41: MakerJuice black: (no photo's)
  • #46 - #56: MakerJuice black: calibration matrix
  • #57 - #61: FunToDo black: calibration matrix
  • #62 - #73: FunToDo black: different objects..

    Time for some new test results:

    Somehow, after a month or so, the FunToDo resin starts to shift a bit to dark green instead of the (original) black... Not all FunToDo resins having this this bad. Maybe the resin was staying too long in the vat..?

    Learnings:

  • Lowering the retraction speed towards 50 [mm/min] gave much better results.
  • Somehow, after 'longer' builds (+30[mm]), there is something going on and the resin will not attach so well anymore..
  • While looking to both resins in general:
  • MakerJuice is much more liquid. This has propably some advantages, getting the liquid flowing in tiny holes.
  • FunToDo seems to be much more flexible during the build. This has propably some advantages while it is more 'forgiving' and also while removing the print from the build plate.

    Time for a new vat floor..


  • I'm not sure what to try next. Some people are using FEP instead of Sylgard. First I want that shutter ready, then it's time for a new vat... I was also thinking about getting more air on top of the vat or make a flexible vat floor (pillow vat) or getting back to active/passive tiling or go for Top-Down approach.. In the mean while, the old vat is still covered under some (black) resin. This will be a nice test, to see what's happening, after >>2 months without printing & without any air penetrating into the Sylgard...

    I also need some more material to build new vat frames. I really like to test FEP on thin PolyCarbonate plates. Also dreaming about an only (FEP) foil solution. This should work best, although this will be a challenging construction..