My new prusa i3 MK3 is printing horrific  

Re: My new prusa i3 MK3 is printing horrific

Your first layer - layer one - is in the NOT GOOD realm and needs to be adjusted.

The setting of z-level at -1.3 implies your PINDA is on the high side. You MIGHT need to adjust it lower to help prevent future accidents. Z-level between -0.75 and -1.00 is my preference.

Fix the PINDA, adjust first layer according to the manual that came with the printer, and then post back.

Also - what is the layer height you are trying to print at? Layers in that whistle look like 0.4 mm or larger...

Re: My new prusa i3 MK3 is printing horrific

the best prep for your bed is to wash it with warm water and dawn dish soap (in the UK use Fairy liquid) by using a wad of clean kitchen paper towel dampen with warm water and put a dollop of Dawn on the pad and scrub (i do it twice at 90 deg to each other holding the plate by the edge as it is a phonograph record rinse under running water and dry with clean paper towel keep touching only by the edge... I do this every other day of printing with both kinds of plate.

then set your live z with this method https://shop.prusa3d.com/forum/assembly-and-first-prints-troubleshooting-f62/life-adjust-z-my-way-t2981.html it is far better than the zig zag method in the firmware

Re: My new prusa i3 MK3 is printing horrific

thank you.

Re: My new prusa i3 MK3 is printing horrific

A good check for first layer is a it should not have a rough surface like the too low in the picture above and when you get a print looking like the good print, you should not be able to pull the lines apart when tugging, at least not without excessive force and you should definately have no gaps between the lines when holding up to the light and looking through.

I would also recommend getting a scraper that uses plastic razor blades like this one:
https://www.amazon.co.uk/dp/B01HPNJNIO/ref=sspa_dk_detail_7?psc=1&pd_rd_i=B01HPNJNIO&pd_rd_w=XCJMf&pf_rd_p=e2bfafb5-111e-4906-b089-5d691a51d45f&pd_rd_wg=dtFnX&pf_rd_r=PYZFQRQYWF11A4MR9MZX&pd_rd_r=856005ef-457a-11e9-acd6-b58bbb4c71e5

It will make it so easy to remove 1 layer and you will not damage the PEI surface. It has not got to be the one above, it is just to show you, find the cheapest, they all use the same blades anyway!.

Re: My new prusa i3 MK3 is printing horrific

A good check for first layer is a it should not have a rough surface like the too low in the picture above and when you get a print looking like the good print, you should not be able to pull the lines apart when tugging, at least not without excessive force and you should definately have no gaps between the lines when holding up to the light and looking through.

I would also recommend getting a scraper that uses plastic razor blades like this one:
https://www.amazon.co.uk/dp/B01HPNJNIO/ref=sspa_dk_detail_7?psc=1&pd_rd_i=B01HPNJNIO&pd_rd_w=XCJMf&pf_rd_p=e2bfafb5-111e-4906-b089-5d691a51d45f&pd_rd_wg=dtFnX&pf_rd_r=PYZFQRQYWF11A4MR9MZX&pd_rd_r=856005ef-457a-11e9-acd6-b58bbb4c71e5

It will make it so easy to remove 1 layer and you will not damage the PEI surface. It has not got to be the one above, it is just to show you, find the cheapest, they all use the same blades anyway!.

I would recommend this also. It is easy to damage a PEI sticker bed.

Re: My new prusa i3 MK3 is printing horrific

Hi. This is the height of the extruder and the PINDA that I have in the printer:

As tim.m30 said, I will try to lower the PINDA a bit. Also, I will recalibrate the height of first layer again, trying to obtain the result of the image posted by him.

Re: My new prusa i3 MK3 is printing horrific

A good check for first layer is a it should not have a rough surface like the too low in the picture above and when you get a print looking like the good print, you should not be able to pull the lines apart when tugging, at least not without excessive force and you should definately have no gaps between the lines when holding up to the light and looking through.

I would also recommend getting a scraper that uses plastic razor blades like this one:
https://www.amazon.co.uk/dp/B01HPNJNIO/ref=sspa_dk_detail_7?psc=1&pd_rd_i=B01HPNJNIO&pd_rd_w=XCJMf&pf_rd_p=e2bfafb5-111e-4906-b089-5d691a51d45f&pd_rd_wg=dtFnX&pf_rd_r=PYZFQRQYWF11A4MR9MZX&pd_rd_r=856005ef-457a-11e9-acd6-b58bbb4c71e5

It will make it so easy to remove 1 layer and you will not damage the PEI surface. It has not got to be the one above, it is just to show you, find the cheapest, they all use the same blades anyway!.

Could I print the scraper? of course, when the printer works well

Re: My new prusa i3 MK3 is printing horrific

A good check for first layer is a it should not have a rough surface like the too low in the picture above and when you get a print looking like the good print, you should not be able to pull the lines apart when tugging, at least not without excessive force and you should definately have no gaps between the lines when holding up to the light and looking through.

I would also recommend getting a scraper that uses plastic razor blades like this one:
https://www.amazon.co.uk/dp/B01HPNJNIO/ref=sspa_dk_detail_7?psc=1&pd_rd_i=B01HPNJNIO&pd_rd_w=XCJMf&pf_rd_p=e2bfafb5-111e-4906-b089-5d691a51d45f&pd_rd_wg=dtFnX&pf_rd_r=PYZFQRQYWF11A4MR9MZX&pd_rd_r=856005ef-457a-11e9-acd6-b58bbb4c71e5

It will make it so easy to remove 1 layer and you will not damage the PEI surface. It has not got to be the one above, it is just to show you, find the cheapest, they all use the same blades anyway!.

Could I print the scraper? of course, when the printer works well

If you sand or file the edge of an old credit card it should be similarly effective...

Re: My new prusa i3 MK3 is printing horrific

I have lowered the PINDA sensor a bit:

Now I will run the calibration wizard again.

Re: My new prusa i3 MK3 is printing horrific

I ran the calibration wizard. the calibration was correct. Then I adjusted the calibration of first layer :

I wonder if that is normal:

I don't understand why now, the Z calibration value is "higher" (or lower, considering the value is negative) if I lowered the PINDA sensor. I can't make the calibration of first layer work with the recommended value by tim.m30

Now, I will print the batman logo.

Re: My new prusa i3 MK3 is printing horrific

Those loops of free, isolated extrusion and y-layer shifts looks like the y-axis should also be addressed. I think your y-carriage is also slipping back and forth out of position relative to the stepper motor.

Check that the drive pulley grub screws are correctly tightened on the shaft. One grub screw must engage the shaft flat. Tighten that grub screw first. Then the secondary grub screw.

Set belt tension such that, with the print bed all the way back, pinching the center of the belts together gets to about halfway to them meeting when you feel tension increase. It should be loose enough that initial pinch requires very little force. If you have it at a good tension, the resistance to pinching together will gradually increase and the the rate of increase rises about when halfway together. That will get you in the ball park. If too tight, the immediate resistance to pinching together is high. You only want to tension to remove slack, not stretch the belts.

Re: My new prusa i3 MK3 is printing horrific

Hi juan.

I think you have been mis informed.

If your live Z value is large. It is because your pinda probe is too low.

Lowering your Pinda requires liveZ to be increased to a larger number

As you found out when you adjusted it.

For safety. You need to reduce the value of live Z first. Then raise the Pinda relative to the nozzle. And then readjust your live Z value.

The Prusa first layer adjustment tool is a bit difficult to use.

Do a search for "Life adjust Z my way"

On the first page there is a link to a zip file containing a sample 75mm square. Set up for PLA, PETG orABS. FOR YOU TO TRY

Regards Joan

Re: My new prusa i3 MK3 is printing horrific

I guess it's too bad when top surface is even worse than bottom surface. :c

TOP view:

BOTTOM view:

Re: My new prusa i3 MK3 is printing horrific

Those loops of free, isolated extrusion and y-layer shifts looks like the y-axis should also be addressed. I think your y-carriage is also slipping back and forth out of position relative to the stepper motor.

Check that the drive pulley grub screws are correctly tightened on the shaft. One grub screw must engage the shaft flat. Tighten that grub screw first. Then the secondary grub screw.

Set belt tension such that, with the print bed all the way back, pinching the center of the belts together gets to about halfway to them meeting when you feel tension increase. It should be loose enough that initial pinch requires very little force. If you have it at a good tension, the resistance to pinching together will gradually increase and the the rate of increase rises about when halfway together. That will get you in the ball park. If too tight, the immediate resistance to pinching together is high. You only want to tension to remove slack, not stretch the belts.

Yes, It looks like a problem in the y-axis. I'm gonna check it

Re: My new prusa i3 MK3 is printing horrific

And as Joan said -- now your PINDA looks too low. And I am probably mistaken in the negative value of the First Layer Cal number in relation to the PINDA position. My apologies.

As for poor positional accuracy. People use the term "grub" screw instead of the proper term "set" screw because they think the small screws look like the tiny animal, a fly larva. But it's common enough many people use it. Remember when checking the two set screws, that you must tighten the one on the flat of the shaft first, then tighten the jam screw, the set screw on the round. FLAT FIRST.

Belt tension is also important: the belt should not have any slop. If you can see any movement at the drive pulley the belt is too loose. The belt should be fully locked in place by the geared pulley.

Re: My new prusa i3 MK3 is printing horrific

Yes. The drive pulley grub screws were not properly tightened, they were loose. But that's strange, I perfectly remember when I squeezed both of them (one grub screw engaging the shaft flat as you said) , and I did the test indicated in the guide and It was fine:

It was weird. Now I will run the calibration wizard again.

Re: My new prusa i3 MK3 is printing horrific

After repairing the y-axis, I did what you said. I raised the PINDA sensor, so the calibration of the first layer value was -1.097. I printed the batman logo again:

Top surface:

Bottom surface:

that look nice, I like it, thanks. I think a better calibration value for the first layer could be -1.100

Re: My new prusa i3 MK3 is printing horrific

Yes, much better.

I agree that the z-offset should be adjusted a bit more negative (nozzle down). That will close the gaps between the extrusion lines on the 1st layer.

Take a close look at the 1st layer and you will notice that the diagonal lines waver a bit rather than being straight. This suggests that one or both axis is slightly loose and they are not tracking together. As you have just fixed up your y-axis, it may be the x-axis is slightly loose in belt tension. Check that as well.

You are definitely moving forward!

Re: My new prusa i3 MK3 is printing horrific

I printed the whistle:

I think the problem is from the 3D model or the print material instead of the printer:

I think the X axis is a bit loose. I will adjust it later.