Soil Blocker for 1020 Trays

There are some great soil blocker designs out there, but I had a need to fill a bunch of 1020 trays and I knew I could fit the footprint on the Prusa Mk3.  The blocks are approximately 38mm square and fill the tray in a 6 by 12 pattern.  The main body of the soil blocker is print-in-place, with the dibblers being separate pieces.

I've only used mine twice so far this season.  It's holding up well and while it does get a little sticky to reset, the blocks come out nice and smooth.  Please note that it is not a multi-material part design.. I just ran out of filament mid-print.

Remember to keep your soil mix nice and wet when making the blocks so they stick together.  You should be able to squeeze water out of the mix.

Printing Instructions

I over-extrude quite extensively for these parts to make them nice and sturdy. You will probably need to bump up your printing temperature by about 10°C depending on your wall speeds.  I go with 30-40mm/s and that gets the parts nice and clean within a reasonable timeframe.

I can recommend using 0% infill for the soil blocker.  It significantly reduces printing times and the thick walls and internal supports do the rest.

Soil Blocker

Wall Width:
0.8mm
Top/Bottom Layer Width:
0.4mm
Bottom Layers:
3-4
Infill:
0%
Support:
No

Dibblers

Wall Width:
0.8mm
Bottom Layers:
3-4
Wall/Perimeter Speed:
15mm/s (very small diameter part)
Spiralize Outer Contour/Vasemode:
Yup