How to change skirt/brim printing speed

[dwilbourn]

I think all parties in this discussion are correct in their own way. As I see it, the brim speed is always faster than the 'model' speed of the first layer but it is changed by the mm/min printing speed and first layer speed percentage.

In my case, I get a nice first (model) layer when I print at 50% for the first layer speed, but this makes the brim print too fast and it often starts to tear and roll. If I drop the first layer speed to 25% then the brim speed is also halved and now prints very nicely at last, but the model portion of the first layer takes an age to print. (25% is probably a bigger drop than I really need but it is a good confirmation of the situation)

I think Pavel is correct to question the logic behind this situation. Printing the first layer well is critical, any problems here will be fatal. For Simplify to acknowledge that there is a need to print the first layer slower than the rest of the model, but then make a distinction between the model and the brim is silly. The printer does not know or care what is model and what is brim, it is all just plastic that needs to be printed. The mechanics of printing will not be different for tracks just because they are destined to be brim or model. The user should have the ability to control all the parameters of that print process without having to sacrifice one (model print speed) just to get to another (brim speed) indirectly.

I would suggest that there be the ability to set the brim speed independently of the first layer speed - or perhaps better, as a percentage of the first layer speed.

David W

[RapidRabbit]

I made some investigation about this because i also think that the speed of the Skirt/Brim shouuld be more controlable.

Let´s start with the "other" tab in the FFF settings:
Default Printing Speed 60mm/s.
For testing Outline Underspeed, Solid Infill Underspeed and support Structure Underspeed is set to 100%.

"Layer" Tab:
First Layer Speed 35%.

Working as expected the first layer including the Brim is 21mm/s.

If you set the parameters in the "other" tab as follows:
Outline Underspeed 50%, Solid Infill Underspeed 80% and support Structure Underspeed 80%, you get the following:

Now the first layer of the object gets printed slower as the Brim because the Brim is handled neither as an Outline nor an Infill.
So one solution would be to handle the Brim as one of these or make the first layer independent of the "other" tab.

Strange things happen if you use the Raft.
With the same settings as the pic above you see that the first Object layer is printed faster than the last Raft layer and ignores completely the "other" tab. The second object layer is printed with the "other" tab taken into account.

This behaviour is not clear to me and seems like a Bug.

Other things i noted:
Why is the Printing Speed Legend not automatically adjusted to the max printing speed? Max speed is 60mm/s, but it´s showing values up to 150mm/s which is never reached.
The first line to get the filament flow started, just before the Brim, is printed faster than the first layer settings. This should also obey the first layer settings.

Version 3.1.0

BR RR

[CompoundCarl]

Why is the Printing Speed Legend not automatically adjusted to the max printing speed? Max speed is 60mm/s, but it´s showing values up to 150mm/s which is never reached.

Probably because you have cooling enabled which allows it to slow down the printing speed if the layers get too small

[dorsai3d]

Why is the Printing Speed Legend not automatically adjusted to the max printing speed? Max speed is 60mm/s, but it´s showing values up to 150mm/s which is never reached.

Probably because you have cooling enabled which allows it to slow down the printing speed if the layers get too small

This likely has nothing to do with cooling. The program does actually scale the legend to the max speed in the print; it's just that the max speed in a print is typically travel moves.

[PavelKrupets]

I was hoping it will be fixed in some near future update but no luck so far. Doesn't seem to be a hard fix (unless I am missing something).