fhting temp issues with bltouch
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In another post I reported some issues with bltouch. At the end conclusion is hard to dispute: bltouch is affected by temperature.
At the moment I really dont have the time to look for a suitable replacement (other bltouch like alternatives probably will have the same issues) inductive/capacitive sensors in wont work with my print beds materials or dont have at the mnoment access to them. So fo the moment, bltouch stays.
Temporal solution now is really ugly: after probing the mesh, I just put a piece of tape to avoid the clip to go down.
Today I did a final tests since I wanted to know if this "pin going down and up" event is a mecanical o electric/electronic.
I did 2 cld prints in order to not damage the pin, and in both prints I did have the event: pin goes down and inmediatly up randomly during print.
Then I repeated the same gcode, but these 2 times, I just disconected the bltouch conector. I monitored both print only for 1 hs (in the previous prints the event would for sure happen at least 1 time in the forst 30 minutes) and there was no event.
So im almost sure this problem is not mecanical, is coming from electronics. Sin ce as stated on the other post noise is discarded as a possible suspect (cable is twisted, also is shielded with special tape, and cable is also away from other cables as fas as possible). Electronics is not my field, but then my guess is something is happening on the bltouch electronics while printing and when electronics temperatures is around 50 degrees.
Hall effect is affected by temperature but I dont know why that would be triggering the pin down event.
So the other suspect is the servo signal being affected somehow??? this queston goes tothe electronics experts here.
So the other question (testing this would really take a lot of time so that is why I prefer to ask) would be: if servo signal could be the problem somehow because of temperature of the electronics, would be good to "shut down" bltouch using the config? Like disabling the pin for example? or disabling both .in and .out pins after msh probing?
Ideas?Thanks in advance
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Is your printer enclosed thus leading to higher temperatures?
I have used BLTouch on a 5 different printers with no issues ever BUT none of them were enclosed.
Frederick
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@fcwilt yes. They have very good eclosures, no active heating but as I described on the originalk post, while printing ABS for example I can reach easily stable 65 egrees C, even printing PLA with bed at 50 degrees only, I can reach 45 degrees on the chamber.
I dont really blame bltouch, it is great to my opinion, it is a device that was designed in an era where enclosed printer didnt exist at the common user level.
I also had like 10 printer working with bltouch for years with no issues at all. This issue arised when using the enclosed ones. -
There are a couple of totally mechanical devices that should be unaffected by temperature.
There is this one which looks well thought out:
It does require some moves and some appropriate part to allow deploying and retracting the probe - but that seems to be the issue with all totally mechanical probes.
I tried a Euclid, which worked, but it had to be stowed/retrieved from a part you needed to add to your printer.
I have a StrykePoint on order and I am hoping it works as well as claimed.
Frederick
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Since the BLTouch relies on a permanent magnet perhaps the heat is enough to weaken the magnet to the point where it can no longer retain the pin.
Frederick
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@fcwilt Thanks for your feedback @fcwilt . To answer both: I dindt knew that probe but... I have exactly the same design for a very hight temperature enclosed actively heatd chamber (it reaches 220 degrees celsius). As far as I can see it is the same (but body in my case is all cnc metal). Works very good but ccuracy is lower than bltouch because of temeprature effects on metal and other details but sill way better than anything else (we have an average error of 0.01mm, wich is way of what it can affect a first layer print ). A good example of a problem being solved in 2 places reaching to the same solution. In this case for the moment I would prefer not having to send a new "touchy" body cnc part (this is how we called this sensor internally) adn try to keep for some more time the blotuch, we have 10 of them deployed)
Regarding the other answer: we can debate if you want in the other topic, because doing it here is like repeaton all again, but trust me: thisis not a mecanical issue. The permanent magnet in no way can be affected by a 50 degrees temp in such way. I would agree if we would be talking of 70/80 degrees. Also they way it manifest is clearlo not a mecanical issue. And as I said in the original post where you can see numerical data, this is happenining on the electronics (blt side, not the duet)
