1

Hi everyone!

I have been playing around with my new Prusa i3 MK2 for a few weeks now but I just can’t get really good prints. This printer is starting to get on my nerves…:frowning:

I have done some prints right after the printer was setup using the included silver PLA, the prints came out pretty good…see pictures…

Now after trying some Fillamentum ABS, things start to look different.

I have the Prusa in an enclosure with 2 fans, one blowing in air onto the rambo board (not blowing directly at the heatbed) and the other one is blowing air out to the top.

I noticed that the life z adjust value for PLA is somewhere around -0.660 and for ABS it’s somewhere around -0.710. ABS has an extrusion multiplier of 1.05.

All prints where printed at 0.2mm layer height and sliced using slic3r.

Can someone tell me why the white Benchy looks the way it looks, and why the white Adalinda and corse ridges near the bottom?

Thanks!

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2

First is you want no drafts or air movement in the chamber. I would get the electronics out of it if you are worried about heat.

Your Live Z is number is a little to the high side but as long as you get a good first layer I wouldn’t mess with it. Try to keep it under -1.0. Ideally under -0.5 is best for good PINDA operation but your good for now!

What are your temps and speeds for the ABS?

Normally ABS like less squish on the first layer than PLA and the extrusion multiplier is generally higher. Are you using the Prusa version of Slic3r? If so I would go with the .2 and the default profile for ABS. to start with.

3

Yes I am using the Prusa version of Slic3r. Also using the Fillamentum ABS Settings, 240 HE and 100 Bed. I noticed that the X belt is rubbing against the Idler, maybe this could be causing some problems?

Problem is…I can not get the belt to be in the middle of the idler…Impossible.

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4

Settings seem ok. And, Benchy looked pretty good overall. AbS is hard to print and takes a while to get the hang of.

The belt could be an issue. Thy Y belt is usually an issue because the motor twists. There is a little brace you can print and put between the motor and the threaded rods to help this out.

On the X belt. I would look at the centering of the drive pulley. I have heard others have this issue. There is a large Facebook group for the original prusa printers that can be helpful.

5

Hi there… have you tried with a extrusion multiplier of 1 instead of 1.05? It seems like is a bit overextruded

6

Looks like you may have a patially clogged nozzle and/or are printing a bit cool. You may also should probably adjust your PINDA height. With that much correction the mesh bed leveling will not be as precise.

7

Hi,

I have an MK2 too, upgraded from MKI, it is a great printer and I have printed a lot already. I am not a specialist on troubleshooting, so I really encourage you to post in the Prusa forums where there are a lot of very knowledgeable, professional people.

It is weird you get these lines. What are your settings in Slicr ? Did you change anything ? Did the self test and calibration of your printer go well ?

8

Well…thanks to the impossible to adjust PINDA…This happened.

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9

Oh no. I really would have left it alone. It was ok and the prints were pretty good just fine tuning. Fortunately it looks like it didn’t damage the bed itself. I would give the bed a good heat and gently see if you can smooth it any.

10

How much heat would you recommend?

11

About the most you can get is about 110 for ABS. It is just a thought that it may settle down a little but I would be real careful also. Don’t want to make it worse! Right now it is near the edge so you should be able to print around it pretty good. I just was worried about calibration that the nozzle might catch it.

For a while I would run initially with my hand on the power switch ready to kill it if it acts up.

Aside from here this would be a good one for the Prusa forums. A lot of PEI gets torn up on new builds!! It happens so don’t despair.

http://shop.prusa3d.com/forum/

12

Thanks for you help!

Already posted on Prusa. You guys are way faster! :slight_smile:

13

They are in Europe so some might actually sleep. Not everyone is over there!! Time difference.

Sounded weird.

14

Im in Europe :slight_smile:

15

Ok then more like the same timezone then! I always figure when I may post something it is the middle of the night there!

16

Ok so I’ve done some more tests…

I printed another white Benchy out of PLA. It looks underextruded. The gray Benchy out of PLA was one of my first prints when I first set up the printer. It was pretty much near perfect.

So I tried to calibrate the extruder…

I marked the filament 150mm above the extruder entry. Then manually extruded 100mm. Did this a few times to get the correct step per mm value.

The starting value was 162.30. After doing the measurements a few times and getting closer to the 100mm sweetpoint my steps per mm ended up at 175.64.

Doing another Benchy now to see how this will be…

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17

Ok, I never did a steps calibration on mine since everything is a known quantity from Prusa, board, firmware etc. I don’t know if it is needed if everything is stock but you can ask to see what people say. I never really hear about it. Extrusion is usually fine tuned via the extrusion multiplier.

Here is a spot on facebook that has good help.

18

Did some more tests…Why is only one side of the benchy affected the way it is?

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19

You might rotate him on the bed so he faces a different direction and see if things change. It is hard to see in the pic what is really going on. What are the temps?