Priming material sticks to nozzle

I have a K8800 since about a year and so far I had several issues that I could solve but there’s one issue that really makes me swear almost each time I use the printer!
It’s related to the “priming” cycle after bed leveling when starting a print.
During this priming the nozzle is very close to the bed and a rather big drop of PLA is build up underneath the nozzle. When done the nozzle usually touches that drop, it than raises quickly for a fraction of second and comes down again before starting to print.
It happens almost every time that the nozzle comes down in the drop of PLA causing it to stick to the nozzle. Result : when the head moves to start printing the drop of PLA or part of it sticks to the nozzle causing an irregularity in the start zone of the print.
I’m a bit surprised that I couldn’t find a topic on this issue making me wonder if I’m the only one who’s having this problem?
Any suggestions to solve this issue?

Greetings,
Robert

Hi @Robert_B

I have another build plate, see Vertex Delta K8800 lovers #6
The prime drop of filament, is just on the edge of the Buildtack, so it sticks better. But I also use a little knife to put the drop, down on the plate just after the prime moment. For further tips, see my other Vertex Delta Lovers items.

Kind regards,
Tom

Hi @Robert_B

I look in the problem again after your mail, and make a little put with a 5mm drill in my aluminum heated bed, that did the trick, tested several times and now it stays at the prime place.

Kind regards,
Tom

Hi @TomE

I used that trick as well : remove the drop with tweezers just before the head moves but it’s a bit tricky.
I also thought of drilling a small recess in the plate at the priming position but that’s not easy in a glass plate and it would also be tricky to align the whole correctly with the priming position each time the plate was removed and put back again. How did you solve that with your heated plate?

Regards,
Robert

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Hi @Robert_B

Go to the link in my first answer, the aluminum bed is more flat than the glass, and is bigger than the glass plate, so 3 exact gaps with a file keeps it in place, see photo.
I use an old PC power supply, a timer and a thermos switch and old PC connectors to connect the built plate with the 12V and the sensor and place it just in-place of the glass plate. Even if you don’t use the heat, it is a better build plate.

Kind regards,
Tom