stu_le_brew

you could try the option in Cura (under Shell coomand) of "Enable Ironing"

Question for you - where are you located in the world I bought (very long lead time) from China a big quantity of grub screws if you are in Europe I could maybe post some to you ? to get you running if its urgent ???

I am pretty sure they are M3 grub-screws, there are several types the ones you want have a flat top not a pointed top Recommend to look all over inside the printer to see if they have dropped out but they are very small

my pleasure good printing S

The movement shown in your second video is absolutely NOT correct there should be no movement at all you need to loosen the pulley an move outwards to prevent this movement

If the belt is rubbing on the wires then they need to be pushed back out of the way, but the rubbing would surely effect all of the print. Its very simple to remove the limit switch (just two screws on the side) and push the wires back looking at the print it would seem to me to be a problem that starts at a height as the first third of the big print looks OK my first thought to solve the print problem would be to check all of the rods are correctly lubricated, then check none of the rods are loose and can move side to side or back to front good luck

I am sure you will buy what you choose to but the original feeder is not (in my opinion) your best choice, the performance of the Bondtech is much superior

no doubt in my mind the correct nozzle is an Ruby tipped one from 3DSolex its called an "Everlast Ruby" available in a range of sizes Not sure where you are located but it is distribute widely (all over the world) You may need to increase the flow rate and temperature to get best performance

It would be worth taking the Bowden tube off and trying with a piece of filament if the tube feels rough. In the five years I have had my UM2 I have changed the tube at least once, some times in a desperate attempt to solve an extrusion problem. You have changed all of the other elements in the materiel feed chain good luck

It may be worth trying a smaller nozzle like a 0.25 for instance, sure it will take longer but it could make the difference

I would not worry too much if you can't get it out, I lost one for a long time and replaced it only to rediscover it (inside the print head assembly) months later when I had to disassemble the print head. I do not think there is any risk of it melting

Question are the materials from the same manufacturer ? The blue on is showing under extrusion, maybe try increase the print temperature

I would very much recommend that you contact Carl at 3DSolex directly, his reputation is very high and has always given me excellent service with any problems.

It could be that one of the pulleys that the belts are attached to is able to slip slightly on the metal rods, worth checking that they are all super tight good luck

My pleasure by the way I am also big fan of the Bondtech feeder (I have the QR version), its great to concentrate on design and not printer maintenance