Purge/Prime line issue  

RE: Purge/Prime line issue

When this issue happened to me I found that I had not positioned the build plate correctly. It needed to be pushed back squarely against the back post. 

RE: Purge/Prime line issue

You are right. But i had this also when i did not changed the build plate. I had this issue at my current print. I am going to monitor this in the next days.

RE: Purge/Prime line issue

I would suggest heating your nozzles up and manually grabbing and undocking each toolhead, and giving it a hell of a scrub with a brass brush.

When this happens to me, it's because the initial extrusion is sticking to something else on the nozzle. It can be a tiny particle of filament goo left behind that can cause this.  After a good brushing, they should all extrude straight down.

RE: Purge/Prime line issue

Instead of a brass brush I use a three times folded (six layers) kitchen towel / paper towel to clean the nozzle. Less mechanical stress on the nozzle/hotend but also higher risk to burn yourself. 🤣 
I'm cleaning the nozzles like that since the MK2. Brass brush is only used when I can't get rid of the gunk using the towel.

RE: Purge/Prime line issue

Posted by: @marc-9

Instead of a brass brush I use a three times folded (six layers) kitchen towel / paper towel to clean the nozzle. Less mechanical stress on the nozzle/hotend but also higher risk to burn yourself. 🤣 
I'm cleaning the nozzles like that since the MK2. Brass brush is only used when I can't get rid of the gunk using the towel.

I tried this, but paper towel seems to encourage the goo to move around on the printhead instead of coming off.  Maybe my technique sucks though. I'm admittedly freshly new to this.