help with Plastic trails

[aistaay]

so i tried to print the hollow pyramid. Left to right. you can see my shortcomings. The plastic trails while bridging different objects is killing me. I tried retracting in Slic3r, had it set to 10 and the gears broke the filament in half. set it to 5 and 6. The retraction on the last print certainly helped.. but it just made a continuous thin strand of plastic between pillars
[img]http://25.media.tumblr.com/0f89ba686412 ... 1_1280.jpg[/img]

I went and followed Polygonhell's Extruder Calibration guide with mixed results. This was sliced using Slic3r. Abs 235C 90C hotbed with hairspray. One corner of the cube is at a nice right angle, while the opposite side has a slight curve to it.
[img]http://25.media.tumblr.com/cb44b5760997 ... 1_1280.jpg[/img]

Here i used Kisslicer. Perfect all around.. so the curve problem with slicer isn't mechanical. How would u guys tackle that curve problem in Slic3r?
[img]http://25.media.tumblr.com/e94d2aae4317 ... 2_1280.jpg[/img]

Here's a hollow pyramid using slicer. whether it be slic3r or kiss, i get nasty trails whenever it tries to print multiple pillars or objects. retraction on kisslicer is a bit hard to gauge. i tried 0.2 - 3, nothing really seemed to help. Either too much trailing or not enough extruded filament. Im stuck, pls help.
[img]http://25.media.tumblr.com/9c919eb7c278 ... 3_1280.jpg[/img]

[Polygonhell]

The pyramid is a difficult print, you'll get less strings at lower temperature, and you probably don't have enough retraction, I run 5mm of wipe and 5mm of retract on KissSlicer. You have to be careful with retraction speeds aswell, too fast and you will get stalls or slipping on retraction, too slow and you will get blobs because the head isn't moving while retracting. I run retraction at 50mm/s.
I'm also not using a stock Hotend, and that helps. For ABS I use an E3D Hotend and for PLA I use a JHead.

Your best bet is to do what I did which is set up a print with say 2 cylinders, set retraction speed to say 30 mm/s, start with say 3mm of retraction, then increase retraction by a small amount and see how it affects the strings, rinse/repeat, then do the same for retraction speed.

[bubbasnow]

i see problems with the base of the pyramid, the final surface layer doesn't look smooth and continuous. this could be a contributing factor not with strings but overall smoothness of the rising arms. what speeds are you printing at?

[Flateric]

Due to the gloss and blobs, I would guess temps may be slightly high. Have you set the correct filament diameter and nozzle size in your slicer settings?

[aistaay]

@polygonhell what hotend temp should i be working in, while i dial in the retraction settings?

@bubbasnow. I was printing at 30mm. Are you talking about the kiss print? The print only had one layer at the bottom and top of the base. I suspected it drooped cuz there was no support. I didnt want to increas layer thickness, loops, or infill because it would affect how the pillars came out.

@flateric i set my temp to 228-235. Filament diameter set to 1.75 nozzle size 0.55

[bubbasnow]

I was talking about the top layer on your base, the big flat surface. Here is one i just printed out

[img]https://lh3.googleusercontent.com/-QPJL ... 000220.jpg[/img]

for KISS im doing 5mm suck/prime with 10mm wipe, layers built from inside to outside (good for overhangs), 3 loops, .35 nozzle .2 layer heights.

as you can tell its not perfectly smooth going up, but i watched a few layers and the nozzle was wiggling the parts a little bit during print. Most of the little burs just come off with my finger nail.

[Polygonhell]

@polygonhell what hotend temp should i be working in, while i dial in the retraction settings?

@bubbasnow. I was printing at 30mm. Are you talking about the kiss print? The print only had one layer at the bottom and top of the base. I suspected it drooped cuz there was no support. I didnt want to increas layer thickness, loops, or infill because it would affect how the pillars came out.

@flateric i set my temp to 228-235. Filament diameter set to 1.75 nozzle size 0.55

For that print I'd print with a temperature as low as I can reliably extrude the plastic, and I'd probably run slower than 30mm/s.
There are reasons to increase temperature with ABS, notable it affects layer adhesion, but it really shouldn't be an issue with that print.