Gaps in mid-layer

Have a problem or question, suggested links/information/FAQ's? Post it here
spinnychick
Reactions:
Posts: 8
Joined: March 29th, 2017, 6:01 pm
3D Printer(s): Hictop, Wanhao

Gaps in mid-layer

Post by spinnychick »

I got my printer in early January and it has been working mostly fine until last week. It started with skipping the first 3/4 of the first line of the skirt and a few random blobby prints. Within a couple days it went to diagonally skipping sections of the layer right after puking out enough filament to fill the skipped section. It also prints occasional lines to the x or y endstops then picks up where it left off.

There were no hardware changes in the past few weeks.

I've tried 4 slicers and 3 cards, and the results are the same each time. The same gcode files work fine on a Wanhao printer, so it's got to be something with the printer.
It's not random, though. If I print the same file 4 times, I get 4 identical fails. Each file has its own pattern of screwup.
Ideas?
Last edited by spinnychick on March 30th, 2017, 9:42 am, edited 1 time in total.
User avatar
LePaul
Reactions:
Posts: 3966
Joined: February 7th, 2016, 10:26 pm
Location: Bangor, Maine USA
3D Printer(s): 24 - Yes I have a problem!
Contact:

Re: Gaps in mid-layer

Post by LePaul »

Any photos or video of what it's doing?
spinnychick
Reactions:
Posts: 8
Joined: March 29th, 2017, 6:01 pm
3D Printer(s): Hictop, Wanhao

Re: Gaps in mid-layer

Post by spinnychick »

Imagegaps by Clothocan, on Flickr

Ignore the lifting and under-extrusion in places-I had adjusted the nozzle distance and extrusion several times to make sure that wasn't causing it.
MTVDNA
Reactions:
Posts: 138
Joined: August 7th, 2016, 10:29 pm
Location: Netherlands
3D Printer(s): Ultimaker 2

Re: Gaps in mid-layer

Post by MTVDNA »

At what temperature are you printing? When I had issues like this it turned out I had set it way too low for the speed I was printing at.
spinnychick
Reactions:
Posts: 8
Joined: March 29th, 2017, 6:01 pm
3D Printer(s): Hictop, Wanhao

Re: Gaps in mid-layer

Post by spinnychick »

I've had the temps everywhere from 195-210 for PLA. The nozzle is still oozing normally when it's stationary and I managed to give myself a nasty burn on my knuckle a couple days ago so I'm positive the temps are ok. I have the speed down to 35mm/sec so I can catch what is happening, too. The only thing that changed is that when it pukes out a bunch of filament before it skips a bunch of lines, the drop of plastic doesn't spread as far because it comes out in one spot.
I've also tried various spots on the bed, tried different spools/colours/manufacturers, and made sure the filament is feeding smoothly.
User avatar
Roberts_Clif
Reactions:
Posts: 1372
Joined: March 25th, 2017, 8:17 am
Location: Washington, State USA
3D Printer(s): Hictop 3DP11/12

Re: Gaps in mid-layer

Post by Roberts_Clif »

I had a similar problem not long ago, I have a PTFE lining inside the throat.

The PTFE had became deformed causing the extrusion to vary erratically.

I replaced the throat and Nozzle the faulty prints went away.
You may want to check to see if the nozzle or throat are partially clogged.
spinnychick
Reactions:
Posts: 8
Joined: March 29th, 2017, 6:01 pm
3D Printer(s): Hictop, Wanhao

Re: Gaps in mid-layer

Post by spinnychick »

Thanks, I'll check that this afternoon!
spinnychick
Reactions:
Posts: 8
Joined: March 29th, 2017, 6:01 pm
3D Printer(s): Hictop, Wanhao

Re: Gaps in mid-layer

Post by spinnychick »

I replaced the arm for the extruder because it seemed a little bent. The filament feeds through smoothly without catching on anything, it's not getting shredded or anything. The throat looked ok. I replaced it AND the nozzle just in case. When i raise the nozzle and heat it up and use the controls to extrude, it squirts out of the nozzle in a nice straight line. I re-sliced my test square with both higher and lower extrusion rates, but get the same results.
spinnychick
Reactions:
Posts: 8
Joined: March 29th, 2017, 6:01 pm
3D Printer(s): Hictop, Wanhao

Re: Gaps in mid-layer

Post by spinnychick »

I tried re-calibrating the e-steps. if anything, it made it worse. every few lines, the extruder would slowly wander off to either the X or Y endstop to peek over the edge of the print surface, then wander back again via a different route. Now it doesn't even seem to be trying to make normal angles. There are supposed to be two rounds on the skirt and 4 perimeters on the test square, too.
ImageWorse by Clothocan, on Flickr
User avatar
Roberts_Clif
Reactions:
Posts: 1372
Joined: March 25th, 2017, 8:17 am
Location: Washington, State USA
3D Printer(s): Hictop 3DP11/12

Re: Gaps in mid-layer

Post by Roberts_Clif »

spinnychick wrote:I tried re-calibrating the e-steps. if anything, it made it worse. every few lines, the extruder would slowly wander off to either the X or Y endstop to peek over the edge of the print surface, then wander back again via a different route. Now it doesn't even seem to be trying to make normal angles. There are supposed to be two rounds on the skirt and 4 perimeters on the test square, too.

If you are using 1.75mm Filament you could upload your g-code and I could test print it for you.
or some else could if you have 3mm filament.

It may be your slicing program settings are not tuned in.
spinnychick
Reactions:
Posts: 8
Joined: March 29th, 2017, 6:01 pm
3D Printer(s): Hictop, Wanhao

Re: Gaps in mid-layer

Post by spinnychick »

Thanks, but I've tried 4 different slicers including s3d, and the same gcode file prints ok on the wanhao. The gcode preview definitely doesn't show giant gaps or extra trips to the edge of the bed. I'm almost ready to see how far this thing can fly.
shocksofmighty
Reactions:
Posts: 51
Joined: February 21st, 2017, 2:42 pm
3D Printer(s): FFCP, HICTOP i3

Re: Gaps in mid-layer

Post by shocksofmighty »

If the extruder head is making erratic movements, I would think you are dealing with a communication (over USB?) or controller issue.
spinnychick
Reactions:
Posts: 8
Joined: March 29th, 2017, 6:01 pm
3D Printer(s): Hictop, Wanhao

FIXED: Gaps in mid-layer

Post by spinnychick »

If the extruder head is making erratic movements, I would think you are dealing with a communication (over USB?) or controller issue.
Funny story.... After a couple cups of coffee and putting the printer on a time-out for the thousandth time (and probably about the same time as you posted the reply), I thought I'd hook it up to USB while it printed to see if the software registered the weird movements. I was still pretty po'd and not thinking clearly, so I selected to print from the computer, not the SD card. The @#$%# thing worked. I tried another file. It worked. I tried the first file again. It worked. All these hours of removing and replacing the same 6 freaking screws and it's the card slot. I'm going to go drink and print now.

FTR, if I had read your reply before I accidentally printed over USB, I would totally have tried it on purpose! :-)
User avatar
jonnybischof
Reactions:
Posts: 310
Joined: February 15th, 2016, 2:48 am
Location: Zurich, Switzerland
3D Printer(s): UMO

Re: Gaps in mid-layer

Post by jonnybischof »

Is the card reader located on the printer's controller board, or on a second board and connected via flat ribbon cable? (I don't know your printer, just have my trusty UMO...).

It could be an EMI (electrical interference) problem. Maybe the card reader data cable goes in parallel with some power cable or motor wires? Sometimes it can help to just shove the ribbon cables away from where they are by a few cm and suddenly everything is fine.
If there are two cables (which is the case on many printers) it can help to just separate them a little bit instead of keeping them close to each other. They can interfere with each other because the cables aren't shielded.
EMI can be a very strange thing to deal with..
User avatar
GrueMaster
Reactions:
Posts: 522
Joined: March 15th, 2017, 8:46 pm
Location: Oregon
3D Printer(s): Hictop 3DP-17, Hictop CR-10S

Re: Gaps in mid-layer

Post by GrueMaster »

Looks like spinnychick has the right solution.
I'm going to go drink and print now.
Couldn't say it better. Thankfully, I live really close to a really good local distillery. They even have ice cream. :-D
Post Reply

Return to “General Questions”