Another support material miracle?

While I was doing some practice prints last night to get used to printing on duct tape something very unexpected happened. Recently, I've been working to get the polymer flow rate coordinated very closely with the extruder head velocity. Last evening I accidently managed to do that with a heretofore unencountered precision in a peculiar situation that produced some very interesting results.

I had laid down an HDPE raft and was trying to print a layer of the Mk 1 polymer pump on top of that. I had had trouble getting the layering interval right and managed to get it about 0.75 mm higher than it should have been. Ordinarily, that would have just made a mess of squiggled extrusions instead of a print.




All the same it made for a rather messy print as you can clearly see. It had been a long day and I had demonstrated that I could successfully print on HDPE, so I nearly just packed it in and went to bed. As I was shutting Tommelise down, however, I reached over to turn off the worktable light and in doing so noticed a very consistent shadow under the right hand side.

I'm very used to seeing that sort of thing when the extrusion doesn't adhere to the raft. In this case, however, the shadow was long and even rather than short and humped. I hadn't seen something like that before, so I used a small metal rule to see if I could determine the extent of this gap.



If I was intrigued before I was astonished when the rule easily slid fully 7 mm under the extrusion.

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