SoliForum - 3D Printing Community — Gaps in beginning perimeter

Re: Gaps in beginning perimeter

2016-10-25T08:32:34Z

In the "coast at end" setting, you're basically not feeding anymore filament as you approach the end of a layer to reduce blobs. If set too high, it would leave gaps since the extruder is no longer extruding at a set distance from the endpoint. Sometimes its caused by a "wipe" operation too, so you have to play with each setting and watch the print carefully to see when the problem occurs.

Re: Gaps in beginning perimeter

2016-10-25T08:29:48Z

You should set the print speed very slow and observe to note when the gap forms. Does it form at the end of a layer during a retraction operation or in the beginning? It matters since it lets you key in on the parameter that is causing the problem. If its a retraction issue, you may need to see if your retraction rate is too high or if the distance is too large. In Simplify3D, there are parameters for "extra restart distance". That parameter would be positive to add more material and negative if you find there are blobs. If the gap happens when you are approaching the end of a layer and before a retraction, it might be caused by a large "coast at end" setting. I don't use Slic3r anymore, but I think there are similar settings on that slicer program.

Re: Gaps in beginning perimeter

2016-10-23T18:47:55Z

It's crashing because instead of using a Percentage value for infill like later versions, it uses a 0 to 1 value. This means profiles across versions aren't perfectly compatible.

Re: Gaps in beginning perimeter

2016-10-23T18:15:19Z

I used 1.0.0RC3 to run dozens of calibration cubes and it turned out that once I re-enabled retraction on layer change, the gap disappeared. Everything is running pretty smooth at .64 extrusion width now. The only issue with 1.0.0RC3 is that it crashes on my system(win7pro) after every gcode export. Bummer, but can definitely be worked around.

Re: Gaps in beginning perimeter

2016-10-20T17:16:53Z

Try 1.0.0RC3 for Slic3r then tweak the extrusion width (tool path) down from .72 until your perimeters touch properly.

Re: Gaps in beginning perimeter

2016-10-20T16:29:48Z

Update: I still get gaps in beginning perimeters using Slic3r with a 0.6mm nozzle on a v6 printing 0.4mm layers @40mm/s on my i3 and 0.8mm nozzle on a volcano printing 0.4mm layers @ 60mm/s on my CoreXY.

I have calibrated my extruder steps, and tried upping the temps a hair. Widths check out when I print 20mm cubes, everything looks great except that damn gap! I tried applying extra length on restart and with the value at 0.3mm I can get nice perimeters, but also a nice little blob when the hotend starts extruding again.

I couldn't find anything related to my problem other than this: http://www.soliforum.com/topic/9985/e3d … gs/page/2/

According to some info in that thread, it might be a Slic3r issue. I'm using 1.2.9, anyone else running a larger nozzle have this issue? What version of Slic3r are you running?

I started trying to use Cura for the CoreXY, but the settings are a little different that Slic3r's settings and I'm not sure I have it quite dialed in yet like I do on Slic3r. Anyone a Cura expert? Do I still want to run 120% nozzle diameter for the widths? Its auto-calculate didn't seem to like that idea when I tried.

Re: Gaps in beginning perimeter

2016-10-08T02:12:55Z

widespreaddeadhead wrote:

Even for a 0.6mm nozzle? I thought you wanted extrusion width to be 110-120% nozzle size?

Yes sorry, my bad I misread what you said. Typically .72 would be a starting point. You'll probably end up slightly less than that. Something like .68 you'll also find that now you are moving more plastic and may need a slight bump in temp. Re calibration is important also and you may need less retraction than your .4 needed.

Re: Gaps in beginning perimeter

2016-10-07T21:41:31Z

Set your slicer for random layer start points. Also looks like you are under extruding for such a large nozzle. Have you calibrated your e-steps for the extruder?

Re: Gaps in beginning perimeter

2016-10-07T18:03:26Z

Yup, I changed the nozzle size under printer settings, and adjusted the extrusion widths under Print Settings > Advanced.

I ran home for lunch and took a few photos of some 1in cubes I also printed to make sure it wasn't the 20mm cube file that had issues.

I had retraction at 1mm length and 30mm/s speed for these ones.

You can see the beginning perimeter gap in the top right corner of this 2 perimeter cube. The outside perimeter printed perfectly.

Re: Gaps in beginning perimeter

2016-10-07T17:25:09Z

I recently changed the hotend on my i3 to a v6 from a lite6, and the nozzle to a 0.6mm from a 0.4mm.
I'm running the stl through slic3r to print in PLA at 0.4mm layers with a 0.72 extrusion width @ 200C

Presumably you changed diameter in extruder settings under your printer configuration and saved it and are using the correct configuration file. Did you also adjust default extrusion width in the slicer under print settings advanced. .

that number is important You can set it to zero but if it is any other number that is not correct it will bugger things up . DAMHIKT.

Re: Gaps in beginning perimeter

2016-10-07T14:27:05Z

Even for a 0.6mm nozzle? I thought you wanted extrusion width to be 110-120% nozzle size?

Re: Gaps in beginning perimeter

2016-10-07T14:11:40Z

Extrusion width needs to be changed to .48

Gaps in beginning perimeter

2016-10-07T13:35:35Z

I recently changed the hotend on my i3 to a v6 from a lite6, and the nozzle to a 0.6mm from a 0.4mm. Now the beginning perimeter of all my single wall 20mm calibration cubes are missing a bit of filament, producing a gap. This follows the whole print up to the top. I ran another set with 2 perimeters and the inside perimeter, which is printed first, still exhibits this problem, but the external perimeter is printed fine with the perimeters printed completely. I usually print 4 of cubes at once, and they all have the gap.

I'm running the stl through slic3r to print in PLA at 0.4mm layers with a 0.72 extrusion width @ 200C. I've tried turning retraction lower and ultimately off, but the gap remains. I tried turning the hotend temp up 10C incase not enough plastic was getting melted but it was still there.

I can take a picture when I get home today but I'm sure my expertly drawn pic can explain what is happening. The red area is where the hotend starts each layer and is where the gap is. All the other walls look great.