edis

why it's 24V if it's powered via L7812?

I think it was a temperature problem. Mostly... to print with 100mm/s i need about 230°C, or to slow down. At the moment i've got a better results by lowering print speed. It very depends of extruded filament volume... to print with 0.1mm layer height i can go with 210°C and 100mm/s, but with 0.2mm that's not enough.. Even if i start with 230C, it starts ok, but then my feeder starts slipping (after ~5-6 layers). And the spring i'd say is very stiff. I think that there is something wrong with my machine. It's not a stock ultimaker, it's my custom made. To heat it up, i use single 6R8 7W resistor, at 19V it has about 50W of heating power. So i think there's a chance that the "core" is at given temperature, but nozzle is colder, and that's why i can get underextrusion. I'll have to check this. No, i haven't enabled "joris". Does anyone know how stiff is the stock extruder spring?

Can anyone give some points for me, how much is fast printing and how much is not. I am printing this part: http://www.thingiverse.com/thing:21182 I am using settings: Layer height - 0,1mm Temperature - 210°C Print Speed - 70 mm/s Travel speed - 200 mm/s Z speed - 10 mm/z. I am using a a different kind of knurled bolt and my E steps are 794,4, this gives me a nice 100mm of filament when i order to extrude 100mm. The problem is that if i print this part, it looks good untill the air channel starts to form, then i get signs of underextrusion, the wall becomes with a lot of small holes. So is 70 mm/s printing speed too fast here? if so why the bottom of this part looks really nice and solid. Or should i pump up my temperature to 220-230? when extruding by hand at 210°C the plastic flows so easy and for me it looks like it should be able to reach even higher speeds with these settings. Anyone could suggest what's wrong here? Edit: It looks like i can't print at all with 0.2mm layer height. I build on glass bed with tape on it. First layer looks nice, but as more layers gets layed, the uglier it looks, for me it looks like its underextruding, but i've tried temperatures from 200 to 230°C, and flow rate from 100 to 130, but still nothing... here's how it looks after 4 layers:

@gr5 thank you so much for this picture

Do you guys also get this kind of "ringing"?

I agree, that's possible. But then it should be the same in the other side, but now it isn't. Only this side and this edge affected. I was printing at 210°C, feedrate was 80mm/s/, but i've tuned to 80% with ulticontroller. So actually there should be actually 64mm/s, so not too much of a speed. Anyway, thank you for the tip, i'll try to adjust acceleration. Yes. at this stripping it looks like there's too little material. I guess that can happen due to retraction, because in the inside there's a support material and in about that place it ends.

When i'm printing a tall part, i get uneven finished walls. One edge is always ribbed, like from vibration and in the vertical walls i get stripes with too less material. but it's like 1 stripe and then it prints ok again... Can anyone suggest who could cause this? Interesting fact is that this stripe is not going though all part, it's on 2 walls out of 3... But i get this ribbed edge on all parts

Maybe there was a jam of some kind? Dust. etc. And by pushing with hand, you provided enough pressure to push that dust plug out?

So, i've tested a symetric part. But before that i've checked my extruder it was extruding too much. now after correction my E steps per rotarion is 794.39....Now it really looks much better at the corners. Here are the results However, the inside diameter should be 30mm. When measuring it varies from 29.6 - 29.9mm. I'll go though my Y axis with dial indicator and check what it shows... This is quite annoying

Try using retraction and increasing travel speed. There was many similar post about such issue :cool:

hmm, that's an interesting thought. I've calibrated my extruder some time ago, will try to do it again. But that still doesn't explain the X-Y dimensions difference. Or is there a chance that under-extruding can make parts not round? I doubt that..

I am expierencing some problems with my axes, thought maybe i can get some suggestions here. For some time now i just can't get my prints to be correct. i think i have some problems with a backslash. When i print square part with a circle hole inside, it's dimensions are different in X-Y axes. I print part with dimensions X50xY25mm and a hole inside of 10mm. The final dimensions are: X49.65, Y19.5. Hole diameter in X is 9.8mm and in Y it's 9.4-9.5mm. Also the circles around holes and fill has some gaps. So i'm guessing it's a backslash problem.Here is my test piece: Reassembled both axes completely, retightened all pulleys, checked belts. Still nothing. And it seems that the belt tension isn't so important, because if i tighten them normaly i get same results compared to really tight, when it's even to hard for steppers to move. Anyway, i used dial gauge to measure my backlash. First, for the reference point i measured Z axis. Results are quite interesting... It looks that i get backlash even with the Z axis, which is moving smoothly. I suppose it's because of the steppers and my ballscrew. E.g. i move stepper forward, then i command to move 1mm back with a feedrate of 50. So instead of 1mm i get only 0.83-0.87mm. Are therse numbers normal? Next i've measured X axis. The belt i'd say wasn't very tight, you can hear a sound by taping it, but axis moves really easy and smootly, without any bumps. (if i tighten them more, i get runout by eccentric pulleys, then by pushing axis i can feel force difference, like half rotation it's easy and half - hard.) Here are the results: Here after moving axis forward and then giving a command to move back by 1mm at 50 feedrate, i get movement of 0.74-0.86mm. Also for some reason all my measurements are a little bit smaller than given number, e.g. if i order to move 1mm it moves 0.93-0.99, but for this i'm thinking that my dial indicator wasn't horizontal. Soo my question is, is this normal for X axis? After this test, i've tried tensioning all belts for X axis, but results were not improved, backlash decreased by 0.02mm, but then it was really hard to move the axis by hand. the movement was like vvvvVVVVvvvvVVVV, the force to move axis also then varies and the motor starts slipping. i haven't yet measured Y axis, since my dial indicator fitting doesn't fit and my dial indicator is too high to hit the wall of my printer.

Same here