BFB3000 loses calibration of Z-height
I have firmware 4.1.0 on dualhead BFB3000. I calibrated z-height using settings menu.
After few days of not using machine i cannot home head because bed goes up
and doesn`t stop, so i have to stop it with esc-key to prevent crashing.
I loaded same firmware to printer to reset settings but it didn`t help.
Manual move works Ok.
BFB3000 has magnetic sensor for Z-height. Maybe I have problem with it...
PAK_Z,
In manual move, are you able to move the carriage to rear left i.e. press X- until it stops then Y- until it stops. Then press Z+/- to move the bed toward and away from the home position. Does the Z TEST / OK indicator change on the screen?
Andrew
When I move head with Y+ X- I get
X limit OK
Y limit OK
When in this position I press Z+- button
Z limit changes from TEST(when it lower) to OK (when it in upper position)
When I move head to X- and then press Y- the head doesn`t stop.
It tries to move further by Y- and crunches.
I get X limit Ok
Y-limit TEST
As for Z+- I can get only TEST because I cannot get it upper. The calibration
is lost now, so bed wants to go upper. Yesterday it was OK today - not OK.
I think that my problem with Z-calibration may be not firmware related.
Having 4.0.2 which don`t have software settings for Z-height I also
couldn`t get calibration that wouldn`t be lost after day or two.
PAK_Z,
The Z limit switching mechanism can only work when the head is in the rear left corner, so maximum of X- and Y+.
Please can you check the limit switch measurements as shown in the attached photos. The measurements are in the attachment filenames. If the Y limit switch is not as shown, this will put the Z limit switch out of alignment which causes non-repeatable Z homing. Please let me know if this is the case.
Andrew
Thank You. I measured Y-limit switch =7mm (or maybe I have to measure biggest size shown on picture with `?`). Z switch = 17mm, it seems to me that it was the problem...
Waiting for your answer.
I think i found a problem >:(
It was not the position of sensors....
It was sensor of Z-height... it doesn`t work...
I made an experiment, i removed the magnet
from Z-screw and moved it closer to X and Y
sensors during movement.
When magnet was close to sensors the movement
by this axis stopped.
But Z-sensor now doesn`t react on the position
of magnet and bed keep moving...
Waiting for official answer from BFB.
The clearest way to carry out the Z screw magnet test on all of the sensors is to go to the Manual Move screen. Holding the magnet next to each of the limit sensors in turn will cause the screen to change from TEST to OK for the relevant sensor providing it is working properly.
From your previous post the Z limit switch was working as you were able to achieve 'OK' on the Manual Move screen, however you are now saying it is not working. If you have attempted to adjust its position and over tightened the holding screw the limit switch will be damaged as it has a glass tube inside which is easily broken by the holding screw. If this is the case, please can you email support at bitsfrombytes dot com with a link to this topic and the details of where you would like a replacement sent to.
Otherwise, please let me know and there is something else that I can suggest you can check.
Andrew
Hi, i think that z-sensor didn`t work properly from the very beginning.
Maybe because of that i couldn`t get proper calibration.
I`ve already written about this problem http://www.bitsfrombytes.com/fora/user/index.php?topic=978.0
Now i can`t get Ok holding magnet near Z-sensor...
I tried opening a support case on a similar item, as I bought my bfb3k direct, but so far the ticket is still sitting in "unassigned". So I guess I'll just try the public forum for help.
When I try to print, the head crashes into the bed. When I tried to home the head, it crashes. When I try to set z height, it crashes.
So I checked the magnetic sensors as discussed in this thread. X and Y limits work fine. The Z limit sensor works when I hold a magnet near it. However, there doesn't seem to actually be a magnet on the bed assembly. The sensor on the head works, but there is nothing attached to the bed that corresponds to the sensor. I can get the Z limit to work by Duct Taping a magnet to the correct position on the bed assembly, and I can see where a manget might attach... but it's just not there.
Is it possible that BFB accidentally shipped my unit without a Z height magnet assembly?
That's issue number 1. Issue number 2 is that, even when I have the Z height limit working properly, the head still crashes into the bed. Specifically:
I tape a magent to the bed assembly in the right spot. I put the XY to their limits, and the manual move screen says "OK" for those. I move the Z height up from there. It changes to OK at the correct spot, so clearly the magnet I taped into place is working. I exit manual move and select "set z height" to fine tune things. The head goes through it's automatic movements... and crashes into the bed.
So what I need is:
1. A photo of where the Z height magnet is supposed to be, so I can verify that it really is missing. If it is, then,
2. A replacement magnet assembly shipped to me ASAP, of course. And either way,
3. Diagnosis of why the Z height set function would crash the head even when the Z limit is working as described above.
Note: In my debugging efforts, I have tried firmware that shipped with the unit, latest production code from BFB site, latest beta code from BFB site, and NetFabb code. All behave the same way.
THe z height magne sits (just under it own attraction) on top of the z height screw adjuster. Once when I was moving stuff around I dislodged it as I said it only uses its own magnetism to hold onto the top of the screw. It is approx the same diameter as the screw thread and about 5mm high.
I am experiencing the same problem and have also posted a support ticket. The magnet is inside the v2 black bed, so cannot be moved. If I position the heads above the magnet, it works fine, however, during calibration or "home" position, the heads are offset to the right by a few cms and then the bed crashes into the heads. I can only assume the z stop switch is no longer as sensitive as it should be or the firmware has a bug. Running the lates firmware v4.1.1d
I am experiencing the same problem and have also posted a support ticket. The magnet is inside the v2 black bed, so cannot be moved. If I position the heads above the magnet, it works fine, however, during calibration or "home" position, the heads are offset to the right by a few cms and then the bed crashes into the heads. I can only assume the z stop switch is no longer as sensitive as it should be or the firmware has a bug. Running the lates firmware v4.1.1d
I'm getting the same issue!
After having used my Dualhead BFB 3D Touch a few times, I turned it on the following day and decided to double check the z-height. I went into the Z-HIGH menu and the head starts moving around. As I glanced to the menu, I noticed the offset was set to -3.xx. I don't remember exactly, but I may have cancelled the operation because the head was sitting in the far left and rear position when I went into Z-HIGH menu again. This time, the offset was set to -8.xx and the head crashed into the bed! I never saved any settings! As soon as I heard the noise, I quickly exited the menu, went into the MOVE menu, and starting to move the bed down. In doing so, I noted that the z-axis values did not correspond to what the z offset read. I turned the bed over at one point, and the z position values were different.
Now I tried to follow along with some of the comments in this thread with the use of a magnet. So, in the Z-HIGH menu as the bed is moving up, I placed the magnet where the sensor was, then removed it, which stopped the bed. I tried to save the setting of the offset, but when I went to the HOME menu, the bed would crash in the head.
1. Is the reading for the offset in the Z-HIGH menu supposd to correspond to the z-position readings in the MOVE menu? If so, the Z-HIGH menu should read both the current offset setting as well as the current z-position. WIthout it, I have no idea when the bed will stop moving up and may crash into the bed. If not, what is the value of the offset?
2. Is there any way I can manually adjust the offset (in the Z-HIGH menu) without having to manually move the bed? Perhaps a factory reset button? =P
3. Is there any other things I can do right now that does not involve a magnet?
Rio
Dualhead BFB 3D Touch / Firmware V5.1.0
Support came through with a brand new PCB running V5.2.0. Ready to go =)
I just came here with the same problem. Z sensor not working. The bed was going up until bad things were happening.
After some troubleshooting, I fixed it by placing a little neodymium magnet under the Print bed. It sticks to the original magnet. I'm not sure why the original magnet is suddenly not strong enough to trip the sensor, but with the extra magnet attached, its working.
Everything going smoothly again.
We are experiencing similar problems with the Z height being non-repeatable. It appears to have happened since we swapped to the black composite print bed a few months ago. I have spent the entire day trying to set the Z height by adjusting the sensor position, and even tried using the Z offset to make finer adjustments. But it just isn't repeatable any longer, it is slightly different each time I print which is becoming very frustrating.
I'm using a BFB 3000 running firmware version 4.1.0d
Any ideas or suggestions on how to resolve this issue before I give up with it?
Ben
I have the same problem now!!
I can't let Z hieght sensor be on the top of the magnet inside during setting Z height, so that it can't stop until extruder and V2 bed are crashed.
It seems like an unsolved problem till now?? Or how did all of you fix this problem??
My firmware is BfB 3000 single V4-1-0s. Is there any version of firmware without these bugs released??
Hope BFB staff can help me soon, thank you :)))
Best to open a support ticket on something like this. Staffers may not get in here that often.
Thanks for your advice :))
I haven't got a 3000 (YET ;D) but I think there is an issue with the z height 'home' switch (read in other threads). I think it just needs setting up carefully. On the 3.0 machines it is well known that the z home micro switch sometimes misses and the bed crashes into the head.
Does it work when manual moving from the main menu?