Just completed upgrade from MK1
Hey everyone - so I am having problems - of course right.
So, about a year and a half ago, I purchased the MK1 and put it together. MAN, that printer has been rock solid the entire time. I just throw the SD card in, hit print and done! Over the entire 1.5 years I have had ONE failed print part way through. When the Upgrade kit to the MK2 came out, I purchased it right away because the sales material made it sound like the best thing since sliced bread! I just couldn't bring myself to doing the upgrade because the MK1 was so reliable and solid. Everything I expected from a Prusa printer!
This past weekend, I needed to change the PTFE tube and figured, since I had to do maintenance, now would be the time to do the upgrade.
For 12 hours, I tore apart the MK1 and built the MK2. Very meticulous at dimensions and measurements to ensure the Y frame was perfect.
Everything in its place, everything square and level I put the new firmware 3.0.9 on there and thought to myself - MAN, this was an easy build, the MK1 was ASTONISHING so, this has to be the BEST printer ever.
Okay, self test - perfect. everything okay.
Calibrate Z - Not so much. First spot just find, second spot shoves into the bed, third spot okay, fourth spot starts hitting the bed and I shut it off.
I can NOT get the Z to calibrate. I have attempted using Facebook in the Prusa page and had some help, but that hasn't changed anything. Here is the thread and discussions: https://www.facebook.com/groups/Prusai3users/permalink/641070842744067/ This link shows everything that was suggested and the results.
I am getting more and more frustrated with this as time goes on. I have walked away and came back with a positive attitude and patience, but nothing seems to change.
The only thing I am wondering is the BED? Can the sensors in the bed be defective???
Re: Just completed upgrade from MK1
There are no sensors in the bed.
You most likely assembled the extruder with inductive probe too high. Bottom of the probe should be 1-1,5mm higher than bottom of the nozzle.
Re: Just completed upgrade from MK1
I have had the Probe all the way against the bed and same height at the nozzle for testing but it does the same thing.
Re: Just completed upgrade from MK1
Hi,
[Edited]: Ok, just seen the Facebook message now.
First thing to check then is to ensure the probe is going at the right place, having the probe sensing the center of each circles is perfect, even if the XYZ calibration can find if the probe is a bit unaligned.
But if the deviation is too much, or the frame not square enough, then even the XYZ calibration will not be able to correct it.
You can check an article I made some time ago before the auto calibration was implemented, that could help to find a good starting build: http://help.prusa3d.com/mk2-movement-calibration/172660-p-i-n-d-a-probe-misaligned
I'm like Jon Snow, I know nothing.
Re: Just completed upgrade from MK1
I have had the Probe all the way against the bed and same height at the nozzle for testing but it does the same thing.
The probe has a red LED at the top of it that is on normally, but turns off when it "triggers". Does that appear to be happening?
If so, then perhaps there is a loose or broken wire connection. Triple check all of those, including where the probe connects to the rambo.
Re: Just completed upgrade from MK1
The red light triggers. I can also put a piece of metal under the probe and it goes off.
I have moved the Z to different heights and moved it back and forth seeing if there is a bad cable maybe and the light stays on.
Re: Just completed upgrade from MK1
Okay, self test - perfect. everything okay.
Calibrate Z - Not so much. First spot just find, second spot shoves into the bed, third spot okay, fourth spot starts hitting the bed and I shut it off.
You mention calibrate Z. I am assuming you meant calibrate XYZ? You need to run through that complete calibration.
Here is the flow diagram from page 12 of the handbook: http://www.prusa3d.com/downloads/manual/prusa3d_manual_mk2_en.pdf
Re: Just completed upgrade from MK1
I know that when I had a similar problem and I contacted support they suggested I lower the PINDA probe. For the Callibrate XYZ, it wouldn't hurt to have the PINDA probe really low, then raise it up until the problem happens again, and then lower it one turn of the top nut at a time. This is how I've calibrated my probe and now I have no problems.
and an 8 inch (200mm) or greater caliper is recommended.
Re: Just completed upgrade from MK1
The red light triggers. I can also put a piece of metal under the probe and it goes off.
I have moved the Z to different heights and moved it back and forth seeing if there is a bad cable maybe and the light stays on.
If you move the extruder above probing points where probing fails, can you trigger the probe by hand (by piece of metal)? It is possible that the cable is damaged and loses contact in outmost positions of X-carriage.
Re: Just completed upgrade from MK1
Yes David, I can trigger it by hand.
Re: Just completed upgrade from MK1
JohnOCFII hit part of it on the head. I was going out of sequence. I hadn't completed the XYZ Calibration.
When I run that - the first point (front middle) is found pretty quick. Then it moves to the second point (right middle). The X and Y move back and forth and Z slowly drops towards the bed. The light doesn't flicker with that normal movement, but then the bed starts doing two small figure eights and I see the light flicker several times when it is doing that, but then it fails and simply says, XYZ Calibration Failed. Bed Point was not found.
Re: Just completed upgrade from MK1
... but then it fails and simply says, XYZ Calibration Failed. Bed Point was not found.
When I first built my MK2, I was lucky enough to pass XYZ calibration first time through. Last week I changed my bearings, and in the process ended up making some small (1-2mm moves) of the nuts. I failed the calibration, similar to your message. I had to get my calipers out, re-measure everything, and realized I had lost the 100mm between the Z frame and the rear corner pieces. Once I re-adjusted the Z-frame washers and nuts to the 100mm distance, it passed calibration again. I was very surprised I had made enough movements to fail the calibration, but I did.
You may need to loosen up the nuts and start to re-measure again.
Good Luck!
John
Re: Just completed upgrade from MK1
So, I have spent numerous hours doing this XYZ calibration. I have gone and manually moved the head to the approximate locations where the LED turns off. I have re-measured (even with different calipers) and have 100mm from the Y Corner and the frame.
The unit goes through the XYZ Calibration, I watch the light flicker at each spot before it moves over to the next spot.
At the 4th point, it flickers, bounces up and down a little, then pauses (with the light out - which would indicate it is right on top of the sensor) and then reports XYZ Calibration failed. Consult the manual.
At least it is now going all the way through all the spots, but why would it fail at the last spot like that and even with the light out, say it failed?
Re: Just completed upgrade from MK1
http://help.prusa3d.com/mk2-movement-calibration/calibrate-x-y-info-and-errors
Check if Y-frame is actually square - measure diagonals, should be the same length.
Re: Just completed upgrade from MK1
It almost sounds like your PINDA probe is mounted too high. I would check that route if your printer is square. But definately measure the printer to make sure it is square. The Y-corners should have a spacing of 151.8 on the inside edges. The Y-motor mount should be spaced 67mm from the inside edge of the Power Supply Y-corner.
and an 8 inch (200mm) or greater caliper is recommended.