Hi everyone,
I’ve found that the nozzle cleaning macro doesn’t really get rid of all the filament which isn’t great for the nozzle tap on the bed. Even when lowering the nozzle a bit more in the cleaning pad not everything is gone.
I’m still trying to improve it at the moment. Has anyone else done some work on the macro already?
I have to double check, but I think it taps the bed once before it cleans.
This is a good reason to use 3 skirt loops.
Not only does it help to remove old filament, but if you have anything hanging from the nozzle it will be in the loop…or somewhere on the plate for you to remove. 
Hmm usually I do either a nozzle clean without skirt or if on a machine without the ability to clean the nozzle a purge line with a skirt. Not both.
On the Prusa Mini it’s even just the purge line without a skirt for the standard profiles I believe.
I have a SV06 Ace and i know that you’re talking about a Zero here . But i have a similar issue. I was thinking about messing around with ending prints with cleaning the nozzle and cooling it down with the fans to reduce oozing because the hot end is still hot. I also wanted to change the temp the nozzle heated to based on the filament was loaded.
Here is an example of an ASA print I did yesterday, you will see it caught it at the red mark.
It’s not what your asking for, it’s just a simple workaround.
There’s at least one issue I don’t have
Yeah in that case I would just omit the nozzle cleaning and check the nozzle with tweezers before the print starts. Doesn’t need to heat up and cool down unnecessarily if it doesn’t properly clean it anyway. But then you still have the fact that the nozzle has to touch the bed for the Probe calibration.
I’m trying to replicate how the SV08 with Eddy-ng does things with tap. That one’s clean everytime and I don’t use a skirt with it.
So your issue is not junk on the nozzle at start of print but at (new to Zero) “tap to set Z offset”.
I see 2 routes, both add time to preprint process
OR
Correct:
I’ve found that the nozzle cleaning macro doesn’t really get rid of all the filament which isn’t great for the nozzle tap on the bed.
Unless someone can correct me that a bit of filament on the nozzle doesn’t matter here because the Zero uses a loadcell/pressure sensor I’ll try to improve it or just omit it altogether.
This is something I thought about together with the retraction, will see tomorrow. Thanks.
Not sure what you mean.
I mean, I have other issues, but not this one.
For general printing, as @Lion mentioned, I omit a purge line and instead use three loops on a skirt to prime the nozzle while also leaving any nozzle ooze on the skirt instead of the part. The travel from the skirt to the part is so short that there is no ooze.
The Zero cleaning procedure seems odd to me. It heats the nozzle to 200 which causes it to ooze. It (hopefully) removes the ooze with the cleaning process. Then it parks the print head and turns on the heat break cooling fan for a minute or more to cool the nozzle to 130 C while it oozes more filament. As @cardoc mentioned, it really should clean that ooze from the nozzle.
My Zero is doing small scale production and I’m running it in auto eject mode where it prints one part then uses the extruder to push the part off the bed, out the front of the printer and into a bin. This requires the bed and nozzle to be free of filament for each subsequent part. I do that by removing the nozzle prime steps from the start G code, printing an oval raft inside the part for the first two layers to prime the nozzle while adhering the part to the bed, and I have OrcaSlicer print that raft modifier before the part so any ooze is stuck to the tear-off raft tag and not my part, and after the part prints, the extruder retracts very slowly so there is plenty of time for the foaming TPU-LW filament to ooze from the nozzle. When the extruder pushes the part off the bed, it takes the raft with the pre-ooze and the long strand of post-ooze that’s attached to the top of the part with it, leaving the nozzle and bed completely clean for each new part. It’s pretty slick. I like programming optimized part-specific solutions like this for production.
