I’ve been getting very poor print quality lately, any thoughts on what’s causing it?
Hey John, whatever machine did you finally end up with?
Heat issues maybe?
This was done on a Lulzbot TAZ. I’ve been struggling to get good prints off of it for months. I thought it was the bushings that they used instead of linear bearings. Replaced them with the linear bearings. I thought maybe my belts weren’t tight enough. They’re nice and tight now. I’m just at the end of my rope with this. I also have an Up Plus 2 printer (you can see it in the background) and it works marvelously. It’s nearly a set and forget machine. I with I had two of them instead of the TAZ.
Looks like you are having some real ooze issues there, have you tried turning the operating temp down. Do a series of ooze tests like http://www.thingiverse.com/thing:22263 and turn the temp down till it starts to go away and you still have good adhesion.
Check also if you’re filament is moist. That can lead to gas bubbles wich will push out more filament.
Though it seems to be worse with edges and small details. So @Ryan_Hescock_Stanos is probably right.
That sucks… first the printrbot and then the TAZ - not a good selection of machines. That looks like multiple problems combined like slipping filament from a messed up drive gear crossed with loose belts and backlash or maybe some of those rigidity issues that machine is notorious for. Good luck!
I just checked my nuts/bolts, and they were loose in a few areas, even on the bottom of the extruder block that connects to the x carriage. Tighten those up! Maybe that’s it?
How cold is your room? It was 20C in my living room when I got home and my print bed took ages to heat up and it was probably giving my filament more shrink than it would if it was warmer.
I’ve been running ABS (230 ex. 110 bed) in a 18C room, and I haven’t been seeing anything like this.
This looks like too much heat or not enough cooling between layers. Print slower, or if you’re using PLA use a fan. Don’t use a fan with ABS unless you have a heated chamber.
This looks like too much plastic, like the others say. The culprit could also be filament with too-wide diameter, or a changed setting for Esteps/mm.
As above, too hot and maybe over extrusion. Sort temperature out first: dont trust your thermistor- do some free air extrusions and gradually reduce the extrusion temp until the filament stops coming out smoothly, then bump up the temp by 5-10 degrees. That should then be a reasonable temperature for printing at 20- 50mm/s.
Next get your flow rate right. I’ve written a wee guide for this: http://reprapstuff.blogspot.co.nz/2013/10/flow-rate-calibration-this-assumes-you.html?m=1
Hope this helps.
@Ben_Malcheski so that is when it is OK to use a fan with ABS. I was wondering about that.
Yep, the idea is that the fan brings the material temperature down fast, like with PLA, so it doesn’t sag. But because the chamber, and air being blown on the print, is at 75C or so, it does not shrink as much.
i think it has more to do with the belts… maybe they have backlash now
John, do you have more photos and maybe a copy of the gcode? Also, what material are you using?