Can anyone please help me?
I removed the mechanism from my laser in order to take out and modify the exhaust vent. After installation, when I powered up the machine, the head tried to find itself as usual. When it reached the rearmost position it did not stop trying to move and continued bouncing against the back of the machine. While trying to figure out what was going on, I used a piece of paper to insert into the U shaped sensor which stops the head from moving backward. It then stopped tying to move backward. I now realized that the small metal plate meant to block the sensor when it reached its far back position was bent and had not been triggering the sensor. I straightened it and checked manually that the stop plate was entering the sensor correctly. However, now every time I turn the machine on, instead of moving to the rear to search for the back most position, the heads first movement is to the front of the machine. It stops as if it had reached the rear of the machine, pauses, then moves slightly forward and to the right as if it has set this as home position. I have tried moving the head to the rear most position with the plate engaged in the sensor before powering up but I get the same result. Can anyone tell me how to set this back correctly?
@timb12957 I had the exact same problem and was resolved when one of the cables for that endstops was out correctly back into place. So check every cable is doing solid contact
@Ariel_Yahni_UniKpty me too. Had one of the cables in backwards.
I have checked the cables. They are all in as they should be.
Just to note they could be where they need to be but a bad connection could still be present.
I tried to make sure they are in tight. At first the head did move to the rear as it always had, but failed to stop(because the stop plate was not entering the sensor) No cables were moved, yet after I used a scrap of paper to insert into the sensor and stop the rearward movement, that is when it began to always move forward upon power up.
Are this mechanical or optical?
The stop is optical
Ok someone recently had the same issue so if cabling it’s OK then the other suggestion would be cleaning them
Ok I can try that. But to point out, the carriage is finding a home position and stopping. Just not in the correct place
Does sound like a cable problem although weird it changed when you tested with paper, what about the stepper cable?
Here is a link to my K40-S schematic which has details of the end stops in case that helps. Ignore all but the end stop intfc tab. Just so happens that I am in the process of wiring my end stops so I am checking these drawings as we post.
http://www.digikey.com/schemeit/project/k40-s-21-8SM4SO8200E0/
I just helped a guy yesterday troubleshoot this problem his was the result of bad solder joints on the pcb the optical endstop is on
Can you take a picture for us of the endstop
I will need to remove the carriage again I think, but I will try to get a pic
Better Pics of sensor PC board. Please remember, the issue is not that the carriage is not stopping, It is stopping at the wrong location. (about midway from front to back)
I don’t see any thing wrong except the sensor looks like it is crooked. Could it have been impacted by the interposer and now has an intermittent. If the collector of the receiver side opened the pull-up could make the signal go high indicating that it is at home.
I would try reheating the sensor leads.
Thank you all for the suggestions but so far nothing has helped😩 I can only hope someone has more insight.
There is always replacing them with mechanical endstops… they are cheap and from my experience often more reliable