Bltouch not deploy sometines it does
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@Tinchus said in Bltouch not deploy sometines it does:
Inside home.z xactly where?
Before and after the G30 where the pin needs to be deployed and retracted.
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@Phaedrux Ok, did it. It works, but as I wrote above, behaviour is really erratic. Sometimes the probe is deployed, sometiomes is doplyed like with a 2 or 3 seconds of delay, sometimes is never deplyed.
Since the post started, I have re donde the conection crimps, I have shielded the cable, I have re donde the crimp again on the duet side conector, I have shorten the cable like -20 cms.
I have been readin a lot of post with similar problems and from there is that I have tried all these posible solutions.
The only one left could be noise? While probing there is no heater on, no fan on either.
ANother observation: leaving the printer on, just IDLE, may be after 10 minutes sometimes after 1 hs, I can hear the bltouch being deplyed and inmedaitly retracted.
I have discarded the posibility of a broken bltocuh, this one was working in the same printer.The only change was: the printer is an old, REALLY old i3 style, instead of decomision it, I though "hey, lets give it a bump, new electronics!" and I used a duet3 board I have as a spare (+sbc). But the bltocuh was connected to a ramp 1.4 arduino mega 2560 and was working really well with no problem at all.
May be there is some campatibility issue with duet? I really dont know how much is has been tested since bltocuh is also a really "old" hardware by now? Just thinking aloud.Logic is 5V? I would like to confirm this before trying to force a 5V logic woirking mode on the blotouch
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@Tinchus said in Bltouch not deploy sometines it does:
I have re donde the conection crimps, I have shielded the cable, I have re donde the crimp again on the duet side conector, I have shorten the cable like -20 cms.
Replace the entire cable to the BLTouch. If the printer is old and well-used, and the BLTouch is as well, I expect one of the wires is frayed or broken from movement somewhere along the cable run, enough to make intermittent contact. That it works sometimes indicates it's not a compatibility issue, but a connection issue.
Ian
Bed-slinger - Mini5+ WiFi/1LC | RRP Fisher v1 - D2 WiFi | Polargraph - D2 WiFi | TronXY X5S - 6HC/Roto | CNC router - 6HC | Tractus3D T1250 - D2 Eth
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@droftarts Ok, new cable installed. looks like situation is much better now but still Im having from time to time the pin droping and then going up very quickly but not enough becuse it hits the print and the pin as bent twice... I saw in real time that: when it happened I saw the red led blink for a second. Rading and reading this could be an interference issue or problem on the 5V line, also some people installed a small capacitor between S and GRND on the bltocuh.
Thoughts? -
Photos of the print head and wiring run?
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@Phaedrux Sure.
On the left there is bltouch an its connections marked as 1 and 2. Cable is new, and shielded with a metal tape. En the right is heatsing fan cable, thermistor and heater cartridge cable all together marked as 3All cables ogether with extrudet stepper motor cable get together on top of the printhead. On the picture you see them but in reality they are all together inside a chain cable (not in the picture since I jhad to remove it in order to do test but since the chain cable is plastic, should not make any difference in fact with cable chain should be worst scenario because all cables are tigheter, still the problem exist without the chain cable.
Numer 4 is extruder cable, number 5 is BL touch cable, and on the right the heater cartridge cable and 6 is the hatsing fan cables. As seen , stepper motor cable is also shielded
On duet side I have bltocuh conection on io7, as you can see on the last part is not shielded (does it matter). Above that there is X endstop connection and next to it the Y endstop copnnection.
The cable markes as SIGNAL bed is a cable that is just like 5 cms close, it si on the pictture but it is a conection from out1 that feeds a mosfet feeding the heated bed.
And this is the metal tape I use for shielding, I guess it works because it solved the noise problem on the flat cable of the SBC in about 8 printers using duet3 on the school.
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That wiring is something else.
Try connecting the bltouch directly to the board with it's short leads and have it stay close to the board and away from everything else while still upright. Do a manual Z homing and start a print and see if you still have issues with the BLtouch behaving randomly.
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@Phaedrux Can you give more specific sugestions on what oyu se as a potential wiring problem, and how you would route cables? If I use the short cable for BL, it is kind of imposible to keep other cables away since they are loner cables Right now as you can see on th pictures BL cables are tgether on the printhead bundle. I have tries to look online for cable steup and ewverything I find are cable bundles, Even if I route every cable apart, they will somehow need to close each other when they get connected to the duet.
Please advise on what potential problem you see on pictures so I can specifically fix that
Are all sure thare is no bug in actual version or if compatible is checked on latest firmware version? Today I noticed something: when pin is not deployed, and if I manually deploy iit, led on BL readcts. If I push pin up with fingers, DWC never sees the BL activation (zprobe value is always cero). If I issue an M402 pins goes up, then M401 deploys the pin and if I try to trigger it, pin is trigger but DWC nevers sees that, probe value is always cero. Then If I do a software emergency stop, the pin drops down, and if I trigger it with my fingers, goes up and gets re deployed inmediatly and I need to turn of power in order to get control again.
Thanks in advance -
@Tinchus I have an extra observation. while trying to separate the BL cable from the resto fo the cables, electronics were off, I moved the printhead by hand and the red led of the bl touch turned on, is that ok?
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@Tinchus said in Bltouch not deploy sometines it does:
@Tinchus I have an extra observation. while trying to separate the BL cable from the resto fo the cables, electronics were off, I moved the printhead by hand and the red led of the bl touch turned on, is that ok?
When you move the motors by hand they behave like generators putting a voltage back into the system which will illuminate LEDs etc. If you move them fast enough you can generate enough voltage to damage the drivers, etc.
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@Tinchus said in Bltouch not deploy sometines it does:
If I push pin up with fingers, DWC never sees the BL activation (zprobe value is always cero). If I issue an M402 pins goes up, then M401 deploys the pin and if I try to trigger it, pin is trigger but DWC nevers sees that, probe value is always cero.
The pin is magnetic, so if you force it up it's going to stay put magnetically, but that's not to say it's the same as triggering. It's best not to touch the pin at all as it's very fragile. And only control it with the proper M401 and M402 commands so that the state of the pin can be accurately tracked by the firmware.
As for the cabling, please try the setup I suggested. If the short leads of the BLtouch itself aren't long enough, try making a short extension harness. The idea is to see if the issue is cable interference or if the BLtouch itself is malfunctioning.
For what it's worth, I run several wires through my harness 1.5 meters to the print head including the heater, PT100, two fans, and BLTouch. All the cables are individually twisted or braided though to limit interference.
