Keeping small strips down

I've been trying to print a few things which have some very small strips as the first layer (5x1mm for example). PLA and using Slic3r. I'm using a heated glass plate with watered down glue, but have also tried blue tape with similar issues.

The strips seem to print fine, but when the head is leaving the strip it leaves just a little "tail" of plastic that sticks up just a bit. This is usually worse if the head is moving back against the direction it was just laying down for the strip. Then with the head moves back over this area it peals the strip up and it all goes downhill from there.

I could try using a raft, but it seems like the chainmail would be nearly impossible to get off the raft. I also have another object that is really large and flat with some small straps next to it that eventually bridge together and a raft on that would be nasty.

Do you think this is a problem with the retraction? (currently the default of 1mm which I thought was OK for wades/gregs extruders). Is there some way to keep the head moving in the same direction as the strip for a while after it stops extruding? Should I increase the head of the bed maybe? Any other ideas?

Thanks for the help! -Bret

Tails / strings when the head leaves a section sounds very much like you're not retracting enough. What temperature are you printing at? Too high a temperature can contribute to the problem.

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[3DKarma.com] - suppliers of quality, affordable 3D printer kits and filament for the UK market.

Currently printing at 200. I've tried 190 but the extrusion width varies too much at 190 but at 200 it provides much more consistent lines. I'll set the retraction to 3mm instead of 1 and see if I notice any help. I can also try 190 to see if that solves this problem, but it will likely create other issues as the extrusion thickness gets inconsistent. Thanks!

I tried a couple of prints with 3mm retraction instead of 1mm and it seemed to make the problem worse. The "tail" as it left the small strip was still there, but then when it started the next piece it seems to leave a little gap and then a big blob. I also tried reducing the termp of the end to 190 but that did seem to cause other problems and everything started to snowball onto the extruder tip (once one piece gets stuck on, it all gets sticky and picks up everything).

Let me give you a few more details about the current Slic3r settings and see if you have any suggestions: PLA, 200 end temp, 65 bed (70 for first layer). Glass plate with watered down glue (tried blue tape too). 0.4mm nozzle with 1.75mm filament. 0.3mm layer height (0.35 first layer with 200% extrusion on first layer). Speed: 30mm/s first layer, 30mm/s perimaters with 70% of that on external. Infill is at 60mm/s, solid infill=50mm/s and top solid infill is 70% of that. Travel speed is 130mm/s. Retraction: 1mm(default), Z lift=0, speed is 30mm/s, 0 extra on restart, min travel after restart = 2mm. "wipe while retracting" is off (would this help?)

Any ideas? Do I need to do some more basic tuning somewhere? Is it something non-obvious like extruding too much plastic? Thanks!

Have you calibrated your e-steps per mm? Under extrusion can cause problems with small-footprint pieces breaking away from the bed as the head can drag the filament instead of laying it down smoothly.

It might be worthwhile playing with the wipe setting - this is supposed to help with tails / strings.

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[3DKarma.com] - suppliers of quality, affordable 3D printer kits and filament for the UK market.

Thanks 3DK. I went through a process where I first ran 100mm through and made sure it was actually pumping through 100mm (right after I calibrated X, Y and Z). I printed out a few things at that setting but it was closing holes and extending past dimensions. So then I went through a process of tuning using "thin walls". I turned down the extrusion to get the wall thickness correct but that seemed way too low when I printed "normal" things. So now I have it set at a bit of a compromise and likely leaning toward extruding more as it tends to work better for most things. I use the extrusion multiplier to turn it down a bit if I'm doing things that need more accurate "inner dimensions". Anyway, I think the extrusion is set pretty well, but I suppose it could be off and I just don't recognize it due to some other issue (and not being experienced).

I'll try out the wipe setting and see if that does anything to help. It will be fascinating to see what it does anyway. Thanks for the suggestions.

I'm here to report back that the "wipe" option really does seem to help. It seems to do a little "curl" with the extruder at the end of each strip which seems to do the trick for keeping the little "tails" from sticking up. In my test print it went from only about 50% of the strips sticking well (no tail sticking up) to around 95% sticking down well without a tail. I think this will be sufficient to fix the problems I was seeing. Thanks for the tips.

This is a lot like a problem I'm having.

Where, please, can I find the 'wipe' setting? I'm using Slicr 1.1.7 for the Mac.

Printer Settings --> "Extruder 1" and then in the "Retraction" box near the bottom is a check box labeled "Wipe while retracting". I hope it works for you. (I'm also using 1.1.7, but for the PC. I imagine they are the same in this respect).
-Bret