February 2019 Puzzler

Samantha Reeve

January 28, 2019 23:06

This next puzzler was printed in PC-Max poly-carbonate on a Gigabot 3+ XLT with full enclosure (and some extra insulation). The smaller piece (top) was attached to the raft and support (bottom) at the top section of the raft. It popped off the raft mid print and the printer kept going giving a birds nest look. Why did the piece separate?

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  Carlos Pozo

  February 08, 2019 21:30 Edited

  it looks like the separation between the support and the raft is not the right amount and because the part is held on a small area at the beginning it runs the risk of this to happen. Also it could be that the print speed is too fast

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  Samantha Reeve

  February 08, 2019 22:45

  The raft separation distance was 0.10 mm where usually the PC raft separation is around 0.30mm, so it was closer than normal. There wasn't enough support to stabilize that section of the part and that helped it pop off, but that isn't the main problem. It was printed at 60mm/s with a 0.8mm nozzle and a mondo hot end. This is the normal print speed for this material and setup. Slowing prints down will usually help, but that isn't the root cause either. 

  Keep guessing! 

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  Carlos Pozo

  February 11, 2019 15:21

  my other guess is that needs a bit more retraction, maybe it deposited more plastic at some point where the nozzle or something in the head grabbed to and pulled dislodging the part

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  Samantha Reeve

  February 11, 2019 15:39

  The printer has more of an issue with retraction and extra restart when layers are very small. The first layer or two after the raft could have been difficult for this print, but that printed without issue. The part popped off well after the point where retraction would cause the most issues. Take a closer look at the part that popped off.

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  Carlos Pozo

  February 13, 2019 18:25

  the layers look really bad, so I am guessing maybe the extrusion multiplier is a bit to low for the speed or the hot end a little too cool?

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  Samantha Reeve

  February 13, 2019 22:27

  Congrats, you got it! The hot end was set to 190C instead of the usual 250C for PC-Max poly-carbonate. The material heated enough to extrude, but not enough to adhere properly to the other traces. 

  Carlos Pozo please contact cat@re3d.org to claim your prize. 

   

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