Raft adhesion issues ? Check the nozzle contour!

Support&troubleshooting Zortrax M200
1

Hi!

I would like to share an issue I had with raft adhesion and how I fixed it. :slight_smile:

I often had the problem that the first lines of the raft would not adhere properly and then the nozzle would hit them and the raft would fail. Over time I noticed that the bad adhesion only happened on lines going “north” and the ones going “south” would always be fine. Here is a picture of one of my failed rafts. If you look very closely you can see that every second line is more narrow (and taller) …and these narrower lines would often not adhere. You can see one of them lifted up in the picture. Wondering why the lines look different with the nozzle going “north” vs. going “south” I took a closer look at the nozzle itself and found the tip to be asymmetrical (I tried to make a picture but it was impossible…for me at least :wink: ). It looked like someone was sanding the tip to its rounded shape by hand and sanded one side more than the other…

Pic of failed raft

I don’t know if the nozzle had this asymmetrical tip on purpose but since this caused me issues I threw the nozzle on my lathe and re-contoured it to be symmetrical. Same rounded shape but even all the way around. The result is now that the lines are the same width in both directions and the adhesion issues and failed rafts are gone.

I may have just gotten a bad nozzle but maybe this info helps someone else. :wink:

2

That is part of the problem I had, but it was my own fault for scratching the nozzle. I too noticed that it was laying a better raft in one direction so I took a closer look at the nozzle and there was a small “gash” on one side of the tip. So I put the spare nozzle on and haven’t had a problem with the raft anymore. The spare nozzle doesn’t work as well as the other when checking Z height though and sometimes pushes hard on the bed.

3

I just realized I posted this in the software section. Don’t know why, sorry… can someone move this to the other “troubleshooting” section? Thank you.

@6uest

You could modify the spare nozzle and give it the round contour… don’t know if you have a lathe. I think your z check is rougher because the flat section builds up a a cushion of ABS which delays the electrical contact a tiny bit.

4

[quote name=Andre]I just realized I posted this in the software section. Don’t know why, sorry… can someone move this to the other “troubleshooting” section? Thank you.
[/quote]

:smiley: :smiley: :smiley:

sensitive subject nowadays… :wink: