Another Bed Unlevel Post (front to back)  

Re: Another Bed Unlevel Post (front to back)

Wow. I count myself lucky with my Genuine Prusa MK2 upgrade build. I get perfect prints and no issues with the MK2 heated bed supplied to me. Back in the day now 🙂 Or are we still talking about incorrect frame build / alignment issues and / or Overtightend belts and misaligned idler / motor mount.

I only point out the above issues, because I built a MK1 Genuine Prusa I3 giving me brilliant prints , and then upgraded with the upgrade kit, with new motors new heated bed and many other mods for the Mk2 , a major rebuild. I followed the upgrade instructions to the letter. And is giving me even better prints.

Re: Another Bed Unlevel Post (front to back)

Hey there guys,

Well I worked the fine adjustments again once I got back and have been getting some reliable prints. Seem to be the same level every print. The difference between different parts in the board isn't as noticeable or disruptive so I can manage with that.

Thanks for the help here. I will keep pushing on making tweaks as I go!

Until next time!
-Lance

That's good to hear! After I did some fine tuning the bed is pretty level.
On a side note: Try to keep your bed probe away from the bed during heating - makes a big difference as well.

-Phil

Re: Another Bed Unlevel Post (front to back)

Try to keep your bed probe away from the bed during heating - makes a big difference as well.

Definitely! I also picked up that tip from Peter in a different post, and configured my gcode to raise the extruded to 100mm before bed leveling. Definitely think it produces more consistent calibrations.

-Lance

Re: Another Bed Unlevel Post (front to back)

So at the risk of nobody listening...

In my opinion, a lot of deformation is because of the way the bed is mounted onto aluminum carrier.

If you get any slop in the hole drilling (particularly countersunk FR4), then when you bolt the thing down, it's going to deform the shape.

It seems to me the lower aluminum carrier should have 1 normal hole and 1 slotted hole in the direction of Y travel. Those set the positioning.

Then you have 2 oversized "floating holes" which, when tightened, might not deform the heated bed.

Re: Another Bed Unlevel Post (front to back)

Hello everyone,

i´m very new, have the prusa 10 days now. I have a kit, Assembling was fine. Meanwhile i did a new setup with xyz, try to be perfect as much as possible.
here are my results from the test print, its not easy for me to say what i have to do now to get a better calibration. i did this print 3 times, its always the same. as you can see down on the left side the square is like damaged and its always like that.

hope you guys can help me.

sorry for my bad english. Hope you understand what the problem is.

best

Re: Another Bed Unlevel Post (front to back)

Nico

What are your current settings for Live Z adjust, and F/B/L/R correction?

I think you need to set Live Z -50 microns, Left & Rear + 75 and Front +50, but it depends on your current settings.

Peter

Re: Another Bed Unlevel Post (front to back)

Hello Peter,

marry Christmas and thanks for your response.

I did a total reset of the printer and re-calibrating it.
i print the PINDA tool from Nerdville and get the PINDA a bit lower.
So right now the print do not change and looks like the one i posted. bit better in the lower corner.
maybe i´m to low with the PINDA right now. Its hard to say for me.
(new PIC at attachment)

z-0.237
i didnt change any other settings. so bed leveling is at 0 at all positions.

thanks a lot for your help

Re: Another Bed Unlevel Post (front to back)

What you have at the moment is a working printer which could be adjusted slightly.

Lower live Z adjust by 30 microns.

Then in the bed level adjust make the following settings:

Left +30
Right -20
Rear +20
Front +20

Just a starting point, but I think you understand. Try it and see how it goes.

Peter

Re: Another Bed Unlevel Post (front to back)

Peter, awesome, thanks a lot.

I understand now how it works.
I'm wondering if this is a normal process to calibrate the printer or is this happened cause I build the printer not well enough.
Should the PINDA normally correct something like this ?

Is it possible to see a perfect printed square how it has to look like.
I feel unsafe cause I don't have a clue how a good printed square has to look like.

Feels good to see that support here at the forum. Thanks

Re: Another Bed Unlevel Post (front to back)

A good square is the one in your last photo, left of the bed, next to the number 55. No roughness, and only very small gaps (which can be corrected in the slicer) between perimeter and infill.

Unfortunately, the inductance of the copper pads in the board do vary across the bed so this calibration is necessary. You first need to get the centre correct using Live Z adjust and then adjust the edges using the L/R/F/B corrections.

Nothing to do with your build!

Peter

Re: Another Bed Unlevel Post (front to back)

Hello Peter,

ok, thanks. thats helps a lot.
i try your settings and its much better, needs a bit more adjustment on the rear but now i´m able to do it by my self.

big thanks ! 😀

Re: Another Bed Unlevel Post (front to back)

Hello and Happy New Year,

i´m back with a little struggle. i tried as good as i can to calibrating the bed. But its seems very hard to find the right setting for the rear and the right. more or less its me of course but after endless printing squares i hope you can help me to come a bit further.

thanks again.

Re: Another Bed Unlevel Post (front to back)

Have you tried placing a straightedge across the bed? It may be warped.
http://shop.prusa3d.com/forum/prusa-i3-kit-building-calibrating-first-print-main-f6/-hump-in-bed--t2668.html
If there is warpage between the sensors, the machine can't compensate for this through the auto-level feature.
If your bed is warped upwards between the sensors there is not much you can do. If it is warped downwards you could probably shim it from the bottom.

Re: Another Bed Unlevel Post (front to back)

Nico

There are times when you just have to say that it's good enough and get on with printing.

And I think you have reached that time. I don't believe that anyone has an absolutely perfect bed. I certainly don't.

Peter

Re: Another Bed Unlevel Post (front to back)

Thanks Guys,

@Peter ok i understand. if it cant be perfect its ok for me, i thought it has to be perfect.

but something for my understanding,
1. for expample if i go up with the right side, did the left side goes down or did it stays in the high i set it.
sometime it feels that nothing happend when i change the settings.
2. make it sense to lower the nozzel and lower the bed at that points where the print was ok to have a all squares filled.

best Nico