I recall seeing a post here on this topic on this forum before but now I cannot find it. For T2 and T3 on my machine C does not fully return to home on tool unlock. It does not get completely horizontal and as such does not fully release or will not full engage on lock. My bet is it is going out of it's register due to friction between the tool plate and the T lock since the docks cannot be adjusted. The senseless homing is too sensitive maybe? I recall a post where it was suggested ithat ncreasing the voltage to the C stepper could solve it and I recall it did. It's currently set to 400 mA in the config. Can whomever wrote that post point to it please...
I finally found the post: https://forum.e3d-online.com/threads/help-c-axis-is-not-homing-properly.3288/ I believe it is the same issue, but I am not too sure the solution is what I was thinking.
HI Andy I was having this issue when I first built the machine, the solution was to raise the current percentage while homing c in homec.g file, but this was already added to the GitHub files on the 16th of august so it should be there if you built your machine after that date.
OK but did you solve it? Seems to me the setup assumes the dock is within a level of tolerance which we cannot adjust to. Is "homec.g" used within FW based commands such as T-1?
Yes this did solve my issue, but if this is the setting you have already then I think you might be having a different problem. One other issue was in the Tprex.g and Tfreex.g gcode files where the location of pickup and drop of needed a to be adjusted specifically the Y value needs to be 243 not 242.5 I checked the github files now and it is still 242.5 so maybe try this change. PS: I would do a manual Move to the pickup location slowly while making sure it will not crash and note the final coordinates just to make sure you are not causing any crashes with the changes you can do this by putting in the commands in the tprex.g into the gcode console one by one..and do this for all tools
I think the intention of 242.5 is to get it close enough to the magnet so it gets pulled into the dock. My experience tells me that moving a homed Tbar manually into the docked tool must go through the Thole without touching. I adjusted accordingly and now every thing seems to work ok until I run the test file. It's tricky to see what's actually happening but it seems to me that it's going out of register in either y or c... too hard to tell. If I run T0-3 commands manually into the console it works reliably. When it runs fast with the test file it misses at T3.
This is the only way to truly be sure and own your own machine and settings. I had mine tweaked well but when i fitted the physical endstops I had to move everything a spot, so I just redid them all again. It's really worth doing this carefully as you can then be sure you'll never have a problem, but it is nerve wracking at times. This is key. Using the console, I used something like this to home in slowly G53 G1 X-5.5 Y200 F5000 Then real slow to test your docking G53 G1 Y230 F250 G53 G1 Y235 F250 G53 G1 Y240 F250 This is really slow and you can nudge X at any time to perfect the dock alignment. When you have it all sorted adjust your tpre and tfree. You can simplify Tpre and Tfre so there's not so much to change also. X is repeated multiple times in the original scripts: https://github.com/e3donline/RepRapFirmware-SD/blob/master/sys/tpre0.g e.g. https://github.com/e3donline/RepRapFirmware-SD/blob/master/sys/tpre0.g#L11 https://github.com/e3donline/RepRapFirmware-SD/blob/master/sys/tpre0.g#L14 https://github.com/e3donline/RepRapFirmware-SD/blob/master/sys/tpre0.g#L17 https://github.com/e3donline/RepRapFirmware-SD/blob/master/sys/tpre0.g#L29 I removed X on all but the first line to reduce the work on any future changes. My current tpre0.x looks like this now: Code: ; tpre0.g ; called before tool 0 is selected ;Ensure no tool is selected ;T-1 ;Unlock Coupler M98 P/macros/Coupler - Unlock M400 ;Move to location G53 G1 X-6 Y200 F50000 ;Move in G53 G1 Y239 F50000 ;Collect G53 G1 Y243.5 F500 ;Close Coupler M98 P/macros/Coupler - Lock ;WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! ;if you are using non-standard length hotends ensure the bed is lowered enough BEFORE undocking the tool! G91 G1 Z10 F1000 G90 ;Move Out G53 G1 Y165 F4000
Yup! For sure you need to adjust per your machine. I have it working OK, but every now and then it misses a lock such as when I manually select a hotend to heat... I assume it is a different setting in a different config file.
When you say, manually select a hot end to heat, do you mean that you press T0 on the DWC? I don't believe it's a different file if so, I think it will still run tpre0 and tpost0. One thing that did catch me out when tweaking all this is the when you switch from tool coordinates to absolute coordinates, the machine actually physically moves before moving in absolute coords, which is a bit strange and can lead to a nasty head crash. I think it's worse than that actually, something like, when T0 is dropped, it at some point feels it necessary to move by the tool offset before taking the next step. In any case, what I observe is that if I don't move back to something like Y=150 after dropping a tool, I can get a smash of the tool head into a tool. I missed lock is most likely the result of not being quite far enough in, or perhaps a missed step in X or Y. To get my Y absolutely maxed before locking the coupler I moved to 240, then slowly move forward 0.5 until you hear it fail. Then look at your Y and set the pick up/drops to that number. I think 240 is probably safe to move to at high speed for all setups, but then push in slow to the final position. Early on I had drops that wouldn't engage the magnet as they were slightly out. That extra 0.5 can ensure it connects.