The first video shows a clogged nozzle and the nut is on the wrong side. I have assembly instructions with lots of pictures. That nut needs to be on the other side or you will get thermal issues. This is an all metal throat, the balance with PLA is tricky and that seems to solve it. As for the nozzle look up “cold pull”, basically you start with a cold printer, heat up the hot end and when it gets to about 100C pull the filament out and it usually brings the crud with it.
Thanks Ryan, I fixed that issue and now am dialing the entire thing in. I’m very close but am having an issue where the “left” side of whatever I print looks terrible but the other 3 sides are fine. I’ve included a pic and links to some video’s showing the weirdness.
Check the y-axis bearings/rods. There’s probably something going on where it moves smoothly in one direction but not in the other (maybe the bed gets cocked or a rod is loose).
Thanks BT. I was thinking something along the lines of something with my bed or bearings but couldn’t figure out why it was only the one side (and the same side every time). It makes sense when you just explained it. The issues are only showing up when the bed is moving in the Y Negative direction so it makes sense that something could be causing it to stutter in that direction.
Edit: I think you called it. I just did some testing with more rapid movements to see if it would exacerbate the problem and moving in the Y Negative direction the bed is shuddering. The interesting thing is - this shudder doesn’t happen if I’m not printing. It only seems to happen during printing functions. Even if I do rapid movements by just sending G-code (G1 Y0 F8000) it doesn’t shudder at all and is very smooth.
Hmmm. I’m thinking there’s some cross talk going on. Does the shuddering occur when the heated bed is on? If so, see if you can separate the cables.
Good question. I’ll have to look into that as well. The strange thing is it’s only in the Y Neg direction. The heated bed and the Y Stepper are in different wire sleeves but I guess anything is possible.
Well, I got sick of redefining insanity by trying to get the thing to print properly over and over and over so I went away and routed out 2 new Front and Back plates and didn’t paint them this time. I was beginning to wonder if I had too much paint in the grooves where the YClips go and it was causing my Y Rods to be slightly “racked” which may be causing too much tension on the bearings. Installing those now and we will see what happens.
I have to get this thing working properly soon - my daughter is begging me for a Purple Giraffe. Lol.
Got the Front and Back flat parts replaced. First test print and it’s doing some weird crap still with the Y axis - at least I think it’s the Y Axis causing the issues. When it does an X Axis movement it’s all good. When it does Y Axis it seems fine as well. It seems to be “bumping” along when it is doing an XY movement at the same time (when it’s doing the infill of the cube I am printing). Here is another video to show what it is doing. Maybe I have some bad bed leveling issues? Something in the Gcode (seems unlikely as I am still using Ryan’s defaults for Slic3r)…
Stranger and stranger - even with all that strangeness, the print I just finished is the best one I’ve made to date…
The infill is also faster. I wonder if that’s having an effect.
I can’t really see the bumping in the video.
You could send some long movement commands and see if you can tell what’s having trouble. something like:
(X)
G1 X10 Y10 F2000
G1 X180
G1 X10
(Y)
G1 X10 Y10 F2000
G1 Y180
G1 Y10
(XY)
G1 X10 Y10 F2000
G1 X180 Y180
G1 X10 Y10
I find I am more sensitive with my fingers than my eyes, so I will rest my hand on the printer while it’s moving and see if I can feel it grinding or lurching or something. Just keep your hand away from pinch points. Feel for the bumping while it’s printing so you know what it is, then try again without printing.
If it’s having motion problems when not printing, then that’s got to be fixed first.
If its only when printing, then its either about the speeds, or the nozzle is hitting the print. If it’s hitting the print, then it could be a temp. or over extrusion problem.
Definitely only when printing. I think I’m over extruding as it looks like the print head is hitting the already laid down filament as it moves. I’m gonna play with adjusting my extrusion multiplier and see what happens.
Did you verify that when you request a specific amount of filament you get it? Mark your filament 60mm from the top of the extruder. Extrude 50mm and then measure from the top of the extruder to the mark - it should be 10mm if it’s not, then your extruder steps/mm should be adjusted. Similar to what you did earlier when you verified the X, Y, and Z motion. You can also check the diameter of your filament in a couple of places to see how close to nominal it is.
I did verify that it is extruding properly (or at least as close as I could measure with my calipers). I did a 100mm extrusion test and it seemed to be accurate but I will run that test again.
I measured my filament to 1.72mm and have entered that into Slic3r.
In the last test print it did, it’s definitely an over-extrusion problem - or something related to that. The only time my print bed shudders is when the print head is doing infill and going over what it already did (I’m using a rectilinear infill pattern). I’ve also noticed that at points in the print I’m getting little blobs of filament. I think I need to start looking into my extrusion multiplier (which is set to 1 right now).
Should I be using adaptive slicing? I’m not at the moment.
I’m also starting out my print jobs with the Z Zero just kissing the print bed. I find that if I lift it up even about 0.05mm then my first layers aren’t sticking. I do need to spend more time leveling the bed I think. I think I’m also going to be a glutton for punishment and route out the Y Plate out of 1/4" MDF. Right now I’m using the Y Speed Plate and since it only has 3 attachment points, getting true bed level seems to be something I can’t achieve (although I really haven’t spent much time with the level since I put in the new Front and Back plates with no paint on them to see if that help).
This will cause it to extrude more.
Nope. That’s more for fine tuning and faster printing.
Remember that the software makes it seem more exact than it is. The extrusion multiplier and filament diameter are tuning knobs to get you what you want. Don’t be afraid to adjust them to something that’s not “right” if it gives you good results. So I would put the filament diameter back at 1.75mm. If that doesn’t fix it, then reduce your extrusion multiplier by 5%. If that works, you can start to tune that closer.
You can also get away with a little under extrusion, but over extrusion, nope. Are you using about a 20% infill? That should help be tolerant to some extrusion problems too. If we can get a good easy print, then we cam make it harder.
Thanks Jeffe - I will do what you suggested and let you know how it goes. I’m using 40% infull but will drop that down as well.
40% should be fine too. Weird.
Well, I set my filament back to 1.75mm and extrusion modifier back to 1 and the infill to 20. I was still having some bumping during the print so about 1/2 way through the print I paused it and raised my Z 0.03mm and that seems to have solved the problem - at least during that print. Definitely getting closer but still not there yet…
While your printing, if you think it’s overextrusion, there’s always the option of adjusting the flow rate. You could tweak it until things come out the way they should.
Good call BT. I adjusted the Z height but didn’t think of dropping the extrusion by about 5%.
You can also look at your retraction settings. When the head slows or stops to do a direction change the pressure in the nozzle allows an extra bit of bead to ooze out. Retraction backs the extruder off just a bit in those cases, minimizing the ooze.