I’m eating up proximity sensors, and I don’t know if it’s standard operation, or what. They’re basically consumables at this point - I’ve used more sensors than hot ends.
To put it in perspective, I’ve had my machine about a year now (but not quite), and I’ve run maybe 5kg of PLA through it in that time. Including the parts that came with the unit when I bought it, I’ve now been through a total of 3 Hot Ends, and I’m on my 5th proximity sensor.
It’s not like I go around smacking it into the bed all the time, even if that is usually my first clue that it’s time to change it out.
Is anyone else having this or a similar experience? It’s to the extent that last time I contacted customer support, I purchased an extra 5 pcs of them just so I have them on hand and don’t have to wait for them to come from China.
The proximity sensor should never need to be replaced, and it should never touch anything. I have only replaced 1 hot-end assembly, and I’ve had my machine since the Kickstarter. I have printed way more than 5kg worth of items, and used many different filament types.
You will need to talk to Support, as there is definitely something wrong with your 3D Printing Module. Support rarely, if ever, visits these forums, so you can’t get any help from them here. These forums are solely used by customers like yourself.
If you’re watching thru proximity sensors then something is definitely wrong. I’m guessing improper install (installed too low). There’s NO way the sensor can go bad unless it’s touching the bed.
I’ve followed their own instructions every time I’ve changed it, including setting the height using the calibration card.
Whenever it fails, it’s always a surprise. The unit will power on. Home the unit. Run calibration, which always works just fine. But then when you go to start a print (I always start with a simple, 5-minute bed level check print - thingiverse 3682545) it will go to the ‘warm up’ position at the front left of the bed, and when the bed & nozzle both reach temp and the print starts, it will drag the sensor and the nozzle across the bed surface. Usually the sensor snaps off when it hits the edge, but not always.
The only time it ever did something different was the very first time it happened. (Printer not calibrating after v1.14 update) The printer would try to calibrate while still at Z Home - so a foot up in the air or whatever. I could jog it around any which way I wanted, but on its own, it wouldn’t lower itself to the bed. That was when I had the thing running for barely four months.
Sensor should be WAY higher than the nozzle, and never touch. The nozzle can be ground into the bed, but the sensor should still be some distance away. The sensor itself doesn’t have to be precise. It only takes readings relative to the final nozzle position (when you use the card). I’d say quit running the test file from thingaverse, and move the sensor farther away from the bed.
I’ve done the credit card thing before, too, though. That was back on sensor numbers 2 & 3. I assumed that the position was too high because it was it was still smacking into the bed.
Right now, it’s at the 0.1mm height. I’ll try and raise it to see what happens, and report back in a month and a half when I have to change it again.
Use the calibration card to place the nozzle at 0.1mm above the bed. Then drop the head 0.1mm so that it is touching the bed. Then adjust the sensor to be 1mm away from the bed, with a credit card.
If it were me and I was confident I’m doing everything by the book and the proximity sensor is repeatedly dying then I’d be asking support for a new toolhead under warranty. Regarding the original post title, yea I think you are the only one, unfortunately. Either there’s a hardware issue or some systematic error in your processes.
Hope you’re able to get to the root cause - it should not be a consumable.
This small bit of information would seem to indicate that your bed is mechanically out of level in a fairly dramatic way, with variation more than the thickness of a credit card.
According to Snapmaker, the bottom of the proximity sensor should be set approximately ONE MILLIMETER above the bottom of the Filament nozzle. NOT just the card thickness, so no wonder you are wearing them out too soon.
I was also thinking the same, the machine may have an assembly error. Mine has been great and still with the original hotend and original sensor, the sensor or the nozzle never hits. Can you post some pics of your rails in the base and the bed frame so someone can check its assembled correctly.
The machine isn’t out of level, and the head isn’t out of square to the bed.Unless eight tenths of one degree matters. And that’s probably just the table it’s sitting on.
This does not make sense to me as I have only calibrated around 5 times for the whole life of the machine, I have printed a lot more than 5kg a year. why do you calibrate so much?
I spoke too tersely to use the word “level” without further qualification. Primarily I mean flatness, deviation from an ideal plane. The SM 2.0 has well-known QC issues with the planarity of the moving bed. Some come out OK, come quite warped. Secondarily I mean that the plane of the bed is parallel to the datum of the X axis in all positions of the Y axis. Ideally this means that the plane of the bed does not change when the Y axis motors move the bed.
I do not mean “level” referring to the machine as a whole with respect to gravity.
Is it not standard to calibrate every time the machine is power cycled? Thought I saw that somewhere… could be wrong.
I see. I don’t notice any warpage or anything being ‘off kilter,’ so to speak. I also haven’t taken any precision measurements on it either. But I did assemble it according to the instructions.
It’s only that front edge. It’s only every fourth or fifth time I turn it on. If you look at the left side of the print bed in that photo above, every one of those gouges cost me a proximity sensor. That’s starting a print, and the head parks itself at that front side of the table while the bed & nozzle come up to temp, and then it will drag itself back over that corner when going to work home.
NO! That would be insane. Only need to calibrate when the tool head is changed. Even then I sometimes don’t bother, unless I find the print not sticking. 9 times of 10, toolhead changes I don’t recalibrate.
