Problems after LCD change--fixed!

[cliffyk]

Like many others I had been experiencing poor results (tearing, distortion, "melting") in prints after changing out the LCD shutter. Am pleased to report that after 7-10 days of trying this. that and the other thing I am back in the printing business. Here is what I found:

Despite my efforts to exactly replace the LCD I found that the replacement sits about 0.001" (25 microns) higher that he OEM screen. as it did not appear damaged I had reused the double-sided tape about the perimeter when installing the new screen. I now suspect that tape became distorted upon removal of the old screen (slightly de-laminated perhaps?) Next time I will remove the old tape, clean thoroughly, and install the supplied new tape.

I any event, that slightly higher mounted position of the LCD was sufficient to cause the FEP (a new sheet installed along with the new LCD) to exhibit a "stiction/suction" between itself and the LCD, creating cured resin release issues as the FEP would no longer bow upward to assist in the release. I read of some using bits of masking tape to raise an edge of the vat and diminish the suction effect--that worked but created slightly distorted prints near the corner of the tank at which I placed the tape.

My final solution here was to spray a tiny amount of silicone mold release on a micro-fibre cloth and wipe a bit of same on both the LCD face and bottom of the FEP.

My print problems were nearly gone, however I found when printing a relatively thick (15 mm) block for storing 4 mm hex bits (the bit holes facing downward as I have done in the past) there was quite a bit of distortion of the block's top surface and at the open ends of the holes.



Suspecting a FEP issue I replaced the "bargain basement" 0.010 mm FEP (6 sheets for $10) with factory spec 0.15 mm sheeting (I also applied the same tiny bit of silicone to the LCD and FEP)--reprinted my organizer and all is well--back to behaving like a new machine.

It is not at all inconceivable that the 0.10 mm FEP exacerbated the initial issue, nonetheless I am quite confident that the slightly higher elevation of the replacement LCD was the initiating factor.

I have also successfully printed a couple (2 at once) of somewhat delicate ferrules to mount temperature probes in a HVAC system's plenums (the flange is 15 mm x 1.5 mm, the tube 5 mm O.D. x 3 mm I.D. x 75 mm long):



I hope this helps some of you out there having similar problems.

[Umpa]

Good write up !