[Closed] First layer calibration not satisfactory  

  RSS
HarrySatt
(@harrysatt)
Active Member

Hi there

I find the First Layer calibration sequence really not very useful. In fact if there is a need for bed level correction the z level is calibrated for the most useless position. In fact left + front you can not adjust with the bed correction possibilities. They are left, right , front and rear.

So I used a different approach. Creating a STL model with 40mm by 40mm square and 1mm thick. Than I position this with the PrusaSlicer right in the middle of the printing bed and print. With this I adjust the live Z level until i get a good fix to the bed.

After that I position the square on the left midlde position and print. With the Bed Correction Left I get a good fix to the bed. Repeating this for right, front and rear I easily was able to get all my Bed Correction values.

Maybe this way to adjust the z leveling would be nice to have in the calibration menu where a square with only first layer can be implemented.

Let me know what you think about this.

Regards, Harald

Best Answer by bobstro:

Posted by: @harald-sattmann

[...] So I used a different approach. Creating a STL model with 40mm by 40mm square and 1mm thick. Than I position this with the PrusaSlicer right in the middle of the printing bed and print. With this I adjust the live Z level until i get a good fix to the bed.

You have described Jeff Jordan's "Life Adjust" procedure. He uses a single layer (0.20mm) high 75x75mm square for calibration. I find straight edges essential for getting the infill-perimeter overlap right. The use of a single-layer allows quick identification of Live-Z issues:

There are variations with smaller squares scattered over the entire bed surface that accomplish the same thing. There are many other variations. I like to use a 3x3 grid myself.

More notes here.

Posted : 04/02/2020 3:04 pm
HarrySatt
(@harrysatt)
Active Member

I tried to send the STL but the file type seems not to be allowed

Posted : 04/02/2020 3:05 pm
bobstro
(@bobstro)
Illustrious Member
Posted by: @harald-sattmann

I tried to send the STL but the file type seems not to be allowed

Try zipping the file before attaching. Zipping compresses files to save space, so Prusa may be insisting on it for files stored on the forum servers.

My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 04/02/2020 5:03 pm
bobstro
(@bobstro)
Illustrious Member
Posted by: @harald-sattmann

[...] So I used a different approach. Creating a STL model with 40mm by 40mm square and 1mm thick. Than I position this with the PrusaSlicer right in the middle of the printing bed and print. With this I adjust the live Z level until i get a good fix to the bed.

You have described Jeff Jordan's "Life Adjust" procedure. He uses a single layer (0.20mm) high 75x75mm square for calibration. I find straight edges essential for getting the infill-perimeter overlap right. The use of a single-layer allows quick identification of Live-Z issues:

There are variations with smaller squares scattered over the entire bed surface that accomplish the same thing. There are many other variations. I like to use a 3x3 grid myself.

More notes here.

This post was modified 1 year ago by bobstro
My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 04/02/2020 5:12 pm
HarrySatt liked
HarrySatt
(@harrysatt)
Active Member

@bobstro

Thanks. What I would like to see is having this implemented in the first layer adjustment and bed level correctin scema in the software of the printer . Would be nice to have.

 

Regards, harald

Posted : 04/02/2020 6:32 pm
HarrySatt
(@harrysatt)
Active Member

@bobstro

I also would suggest to implemennt correction values also for the corners as there are nine calibration  points which all should be able to come into account for the correction trapezoid. anyway. at the moment i only have trouble if I try to print in the rightmost front corner close to the edges. seems that i can not adjust this position because otherwise I get trouble in the middle.

thanx and regards, harald

Posted : 04/02/2020 6:39 pm
bobstro
(@bobstro)
Illustrious Member
Posted by: @harald-sattmann

[...] Thanks. What I would like to see is having this implemented in the first layer adjustment and bed level correctin scema in the software of the printer . Would be nice to have.

That may well be possible with the new generation of 32 bit controllers. My understanding is that the 8 bit controller firmware used on the current Mk3 is very cramped for space, so there's not a lot of space for such things. I recall other printers have used cards on the SD card to do similar things, but I suppose that's not much simpler than simply loading one up yourself.

My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 04/02/2020 6:43 pm
HarrySatt
(@harrysatt)
Active Member

@bobstro

Hi

Thanx. What you mean with loading up yourself? Can I upload correction values myself?

Regards, Harald

 

Posted : 05/02/2020 7:50 am
bobstro
(@bobstro)
Illustrious Member
Posted by: @harald-sattmann

Thanx. What you mean with loading up yourself? Can I upload correction values myself?

I just meant starting a print from the SD card manually rather than having code in the firmware to do it.

Sorry for any confusion.

My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 05/02/2020 2:20 pm
Share:

Please Login or Register