Gap in external perimeter

[sundewzer]

Slic3r does have the ability to random the starting points but then the entire outside perimeter looks like someone drilled a bunch of small holes in it. I think it has to do with the start and stop point as well but I am not sure how I can tell it to stop 1mm later then it wants. I have some blue PLA that should show the defects better. I will get some better pictures uploaded this evening.

[sundewzer]

Here is the better picture I promised. I tried all the tip and tricks that were suggested but I still can't get rid of that gap. Using a hollow cylinder I found out there there is the inverse on the ID. There is a nipple where it starts/stops the inner most layer. The thicker wall made no difference, upgraded to slic3r 1.2.6 which was better the 1.1.7 out the gate but the gap is still there. I tried to change my extruded width and I tried adjusting the overlap. Anyone have any other options?


Since the last one didn't work here is the url as well
https://lh5.googleusercontent.com/-c...331_205532.jpg

[Wolfie]

Well, this is a long shot but...
Have you calibrated your extruder? Is it possible its under extruding due to mis-calibraton?
https://www.youtube.com/watch?v=JZGdMc2ebPo
I made a web page tool for helping to the calculations...
http://wolfiesden.com/TAZ/ExtruderCal.asp (should work with any printer)

S3D has a setting called "Coast At End". Possible you have a similar setting in slicr and its set too high? I use it with compressible filaments like FlexPLA and such to compensate for ooze. Basically it tells the extruder to stop extruding x MM before the end of travel and let the ooze take care of the rest of the track. Then I have it lift Z and retract to stop ooze and release filament compression.

Combine the Coast with an under extruding condition from a mis-calibrated extruder, it might produce your gap.

[3dkarma]

Do you have a bulge on the top surface of your print? It looks like you do from the photo. If you are, you're over-extruding - try dropping the extrusion multiplier by two percent increments until it goes away. The nodules at the back of your print may be caused by insufficient retraction. These two factors may or may not have an impact on the indent on the outer surface of your print.

[sundewzer]

Thanks for the suggestion I tried them all and again no success. I check the extruder length and it was spot on. I tried under and over on the extrusion multiplier. When I went over it got better at 1.05 but then the bulges at the top got worse. I just can't see to win this game.

[Wolfie]

Ok, I guess, one last suggestion...rotate the model 90deg (z-axis) on the bed. Does the line move from the front to the left/right? If so, its the model. If not its gotta be something in the slicing or possibly machine. From prior comments, I don't think it will make any difference. You said when you chose random start positions, the same effect (a gap) appeard all over the model? Yes? If so that says slicing as well. It also seems to eliminate mechanical slop (loose belt for example) which would show itself in a particular axis.

I presume you covered the basics like making sure the filament diameter, nozzle diameter, etc are set correctly in the config file for the slicer. I am out of ideas if this doesn't cover it. I just don't have the experience yet to get any deeper. I am still new at this too.

Why not download Cura and KissSlicer and see if either does any different than slicr?

[sundewzer]

When it is set to random you see a gap on every layer where it start/stop the external perimeter.

I am quite certain it is in the slicer program. I used Cura in the beginning because with the same setting it was faster but Slic3r was always more accurate on dimensions and cleaner. I have check and double checked all my settings. I guess the only thing I don't know for sure is the nozzle diameter, I read that it was .4mm but I have never measured it. I might try KISSlicer but I love having the slicer in Repetier Host. It is just so simple to make a small change and click print.