Friday, 29 January 2016

A failed print, and a design flaw

I did two prints this morning. First I did a larger version of the earlier dreamweaver. However, this was large enough to get the fan out to the clips holding on the glass plate, with predictably disastrous results:

The thing at the bottom is most of what was stuck to the extruder hotend. It's almost but not quite a mold of the hotend.

I peeled off the bits and tried a smaller version. This one fit, but was severely underextruded:

I expect this was due to the previous print having given enough backpressure to cause the filament to strip. I'll check on that tonight. Alas, the new bolt from has not arrived yet, a week after it got shipped.

While I could prevent the situation in the first print by using flat clips or taping around the edge, I do find the fan placement to be a design flaw, the first real one I've found. Having the shroud around the hotend is cool, but the fan doesn't need to be in any particular place, so having it low and in front of the extruder is unnecessary. It makes it likely to hit things and blocks the view of the print in progress. It should be possible to place it vertically off to one side or something. There's a decent amount of space on the right side of the X carriage where it would fit nicely.

1 comment:

  1. You need to remove the top handles from the clips to clear the duct. Or you can replace them with 3mm photo frame clips if you want to print right in the corners.

    I don't believe there is anywhere else a fan of that size can be placed other than at the front.

    I recommend the clips are placed as the assembly diagram for best glass stability. The idea is to clamp it to the PCB close to the pillars.