Hotend filament sensor not stopping the load  

RE: Hotend filament sensor not stopping the load

-The sensor passed the self test. 

-I have tried the spring loaded tension from unbelievably loose to unbelievably tight

-the sensor works fine with the aforementioned screw completely removed. (the sensor sees it but it obviously cannot extrude)

I searched quite a bit and it seems like a couple people have had this problem, but I don't see any solutions. Any ideas? 

 

Thanks in advance!

Have you tried loosing the the bolt that holds down the IR sensor assembly and moving the whole assembly slightly towards the right of the body? 
In the directions it said to line it up with the left hand side.   But i found a more consistent read when it was moved slightly more to the right. 

RE: Hotend filament sensor not stopping the load

Hi,

I had a perfect working I3 MK3 with MMU2.

Upgrading to the MK3S with MMU2S I found some issues and solutions;

Issues after upgrading:

-  Feeding from MMU2S to Extruder(MK3S) didn't work as before, loading, grinding issues etc. etc.

Solution workflow:

1) Rule number one:

Forget about the trial and error solution finding, know what you are doing before starting to tweak a lot of parameters. I am a 100% factory settings addict unless I know for sure what I am changing and for what reason!

2) Rule number two:

Put your MK3S and MMU2S into single filament mode and start printing eg. Buddy. Observe the behaviour of the MK3S and MMU2S very close.

3) Rule number three:

After every failure open the idlers, both Extruder and MMU2S and clean it in order to remove any filament particles left. Use a soft copper wire brush to clean the BondTech gears carefully, vacuum cleaner on top of it! Don't reverse the PTFE tubings in the MMU2S, instead be sure that your new filament tip has a center tip instead of the diagonal cut as showed in the manual. Just make two diagonal cuts leading to a center sharp filament tip.

4) Check the IR chimney behaviour:

In my case I forgot to shift it a little bit to the right after removing the Allen key as mentioned in the manual. You can see this during a print selecting the Support/Sensor status. In my case it was continuous changing from 0 to 1 during the test print!!!! This is NOT good.

5) Perform an individual filament calibration:

Just performing a calibration on filament #1 will do. Why? During the upgrade it is most likely that you remove and and (re)attache the PTFE cable between the MMU2S and Extruder many times. This could influence a proper feeding between the MMU2S and the MK3S extruder. In my case it pushed the filament into the BondTech gears of the extruder a little bit too far, resulting in a kind of noise you don't want to hear..........

Conclusion:

Now my MK3S/MMU2S is working perfect!

This is just my way of troubleshooting, I hope this contribution will help you all with our shared passion!

Don't forget you have a very well engineered piece of equipment at home! Even with ultra high grade 3D printers worth > € 400.000,- you will face the same challenges....:) I know based upon my own experiences...:) 

RE: Hotend filament sensor not stopping the load

It was the extruder filament sensor calibration, I must have missed that part when assembling. Thanks guys!