Tool sensor stuck
The sensor in one of my tools seems to be stuck. So I go looking for how to fix it. Unfortunately there's nothing I can find which shows how to break down the Nextruder to get to this thing. The only breakdown instructions are for the MK4 and it states that it's not for the XL.
Am I going to have to take it apart without any support from Prusa?
Anybody???
RE:
First check the connections at both ends are secure.
Then try swapping the head with another and check whether the fault stays with the head.
Most of the instructions you need are on: https://help.prusa3d.com/guide/how-to-replace-nextruder-heatsink-xl-multi-tool_559633
Cheerio,
RE: Tool sensor stuck
I took it apart. Holy crap what a pita! NOT designed for end user maintenance at all.
The sensor was totally gunked up with material from the filament. I cleaned it and the drive gear and then putting it back together was a super big PITA!! The unsupported stepper motor shifts away from the tips of the screws making it a real difficult task. I get it all back together and nope it still doesn’t work. I can feel the filament pushing the ball out of the way but it don’t work.
This is the very worst design I’ve ever seen.
RE: Tool sensor stuck
I was able to get the sensor to work. I had inserted it upside down.
Chances are every Nextruder will eventually need to have its sensor cleared… not just this one on my machine. Every user with a printer with a Nextruder will need to take it apart to clean this sensor as well as the drive gear, yet Prusa did not design it for ease of access. The tear down images referred to in Diems reply does not actually focus on this maintenance task at all. The three plastic covers have to be removed so that you can support the motor and press it forward to engage the gearing, the motor needs to have something pressed behind it to sit it square against the bracket or the three bolts will not engage. The planetary gears need to be held together (as stated in the referred to tear down) but doing that in practice is not easy. The bolts need to be threaded almost all the way out to get the assembly to be removed. Putting it all back together is not easy and not at all appropriate for a regular maintenance task.
RE: Tool sensor stuck
I also had it from time to time ... I only see the way of cleaning it from time to time. Some of the filament "dust" from the drive gear gets deposited in the filament sensor with unloading the filament ... and since the steel ball is quite as big as the hole and the spring only is reasonable strong, it can get stuck.
It is the same with the XL and the MK4 extruder unfortunately. The idea with the hall effect sensor is quite cool, but it also has some drawbacks.
Taking the sensor out (the mechanical part of it), cleaning it and putting some silcon grease (very little, the Prusa supplied greas or something very similar) behind the ball prolongs the intervals quite a bit.
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