Mini purge before hitting prime tower on hot end swap

Stringing on prime towers introduces unnecessary risk in the print area. So many prints have failed due to the prime tower getting knocked over, It’s giving me Ender 3 vibes! Maybe it’s something else, yet I’d be OK with a little more extra purge waste if on every nozzle swap, the first few mm of filament is dumped out the poop chute before hitting the prime tower. It doesn’t have to be a lot.

Is there a G-Code instruction I could add to my prints to have it do that?

The prime tower is actually designed specifically to absorb problems with printing, which is why it doesn’t exactly look pretty. To put it very simply: If the tower looks bad, you know it’s doing its job - as I said, that’s a huge oversimplification.

What does your prim tower look like? Any photos?


Do you have any photos of it? The failed prim tower may be the result, but it is not necessarily the cause.

You could always use the new “No Sparse Layers” option to reduce the prime tower height.


I ended up utilizing the replacement plan for my H2D and swapped it out for a new one. Prime tower looking much better on the newer one. And I guess I am wrong about the purpose of prime towers and are a necessary evil. I guess something else is knocking the prime tower over

Most failing towers happens at 75% it’s over extrusion building up over time, you probably don’t notice for short prints

This totally checks out! Would that explain why the hairs get longer as the print progresses? Small prints are no problem. Anything over 400 layers at .2mm was at risk. Replacement unit is playing nice for now. Any recommendations on compensating for that over extrusion build-up? I’ll see what I can find in the mean-time

If you mean the nozzle starting to extrude in the air before hitting the tower, you can visualize the path in the slicing preview. I don’t know why they decided to make it doing that, I have no issues on the models

Where I am located there’s a really nasty heat wave happening upper 90’s to lower 100’s. The unit is in a garage with no air conditioning and no means to cool it down. Can’t have it inside the house either. Despite replacing the unit I began to have the same type of failure on the same model. I’m thinking that it’s just too dang hot.

I think you could do just fine with a dehumidifier

Dehumidifiers in an enclosed space make the air warmer, not cooler.

Entropy, yo.

Of course, the best thing would be not to bite off more than you can chew.