ninano
Posts: 2
Joined: Mon Oct 12, 2015 6:17 am

speed down at the corner

Hi, I want to modify the specific speed at the corner.


For example, square outline code is on the below.

G92 E0
G1 X100.200 Y97.700 F488
G1 X129.800 Y97.700 E0.3619
G1 X129.800 Y127.300 E0.7238
G1 X100.200 Y127.300 E1.0857
G1 X100.200 Y98.700 E1.4354

I want to speed down as the nozzle approaches to the point of square. Is there any option on edit process settings?
On 'Other' tap there is Speed settings, but I cannot find any acceleration/deceleration option.
Attachments
simplify3d.png
MasterFX
Posts: 208
Joined: Tue May 20, 2014 11:23 am

Re: speed down at the corner

Acceleration/deceleration is done by the printers firmware itself. On Marlin based printers you can modify Acceleration and Jerk in the firmware (over the menu).
All of the parameters are not part of the slicing process, this is why the calculated time and the real printing time can be very different since the slicer doesn't know what the printer does especially on corners.

On Marlin you can also set jerk and acceleration with the G-Code M201 and jerk with M205
Rebekah_harper
Posts: 263
Joined: Wed Jan 21, 2015 10:25 am

Re: speed down at the corner

the new cura slicer manages to adjust acceleration very nicely.
MasterFX
Posts: 208
Joined: Tue May 20, 2014 11:23 am

Re: speed down at the corner

Rebekah_harper wrote:the new cura slicer manages to adjust acceleration very nicely.
Well Cura still does not acceleration control. It only sets the firmwares acceleration depending on the feature type:

;TYPE:WALL-INNER
G1 F2100 E7.67254
G1 F1800 X134.4 Y95.6 E8.1415
G1 X134.4 Y114.4 E8.61047
G1 X115.6 Y114.4 E9.07944
G1 X115.6 Y95.6 E9.54841
M204 S5000
G0 F3600 X115.2 Y95.2
M204 S3000
;TYPE:WALL-OUTER
G1 F1800 X134.8 Y95.2 E10.03733
G1 X134.8 Y114.8 E10.52625
G1 X115.2 Y114.8 E11.01518
G1 X115.2 Y95.2 E11.5041
M204 S5000


In my opinion the the default acc settings should be set in the printer correctly. Of cause it maybe take a little bit longer on the not visible parts but, I don't know if this is a must have. But you are right, in some cases it maybe a nice feature to have more control.
brian442
Posts: 1243
Joined: Mon Nov 28, 2016 5:35 am

Re: speed down at the corner

It seems a bit odd to need different acceleration or jerk settings when printing either the inner or outer perimeters. I usually set the max acceleration and jerk settings based on what the mechanical hardware is capable of, so I personally probably wouldn't be changing these constantly for different features on the model.

But if you really wanted to in S3D, you can do the exact same thing by adding the M204 commands before each feature type. Just add something like the following to your post-processing script:

{REPLACE "; outer perimeter\n" "; outer perimeter\nM204 S3000\n"}
{REPLACE "; inner perimeter\n" "; inner perimeter\nM204 S5000\n"}
Rebekah_harper
Posts: 263
Joined: Wed Jan 21, 2015 10:25 am

Re: speed down at the corner

MasterFX wrote:
Rebekah_harper wrote:the new cura slicer manages to adjust acceleration very nicely.
Well Cura still does not acceleration control. It only sets the firmwares acceleration depending on the feature type:

;TYPE:WALL-INNER
G1 F2100 E7.67254
G1 F1800 X134.4 Y95.6 E8.1415
G1 X134.4 Y114.4 E8.61047
G1 X115.6 Y114.4 E9.07944
G1 X115.6 Y95.6 E9.54841
M204 S5000
G0 F3600 X115.2 Y95.2
M204 S3000
;TYPE:WALL-OUTER
G1 F1800 X134.8 Y95.2 E10.03733
G1 X134.8 Y114.8 E10.52625
G1 X115.2 Y114.8 E11.01518
G1 X115.2 Y95.2 E11.5041
M204 S5000


In my opinion the the default acc settings should be set in the printer correctly. Of cause it maybe take a little bit longer on the not visible parts but, I don't know if this is a must have. But you are right, in some cases it maybe a nice feature to have more control.

fair one. I only do the setting in the slicer adding acceleration control settings there so I couldn't confidently comment on that.
it might be down to the printer allowing it it happen but I like the acceleration function in the slicer as it makes for a smoother print movement and allows me to print faster without things peeling upwards.

I'll have look at it my self to see what I can learn.

many thanks.

Bex
jfkansas
Posts: 133
Joined: Wed Oct 01, 2014 2:12 am

Re: speed down at the corner

The inner walls can be printed faster because they aren't seen. Any speed related ringing artifacts can be mostly hidden by running the outer wall at half speed.
brian442 wrote:It seems a bit odd to need different acceleration or jerk settings when printing either the inner or outer perimeters. I usually set the max acceleration and jerk settings based on what the mechanical hardware is capable of, so I personally probably wouldn't be changing these constantly for different features on the model.

But if you really wanted to in S3D, you can do the exact same thing by adding the M204 commands before each feature type. Just add something like the following to your post-processing script:

{REPLACE "; outer perimeter\n" "; outer perimeter\nM204 S3000\n"}
{REPLACE "; inner perimeter\n" "; inner perimeter\nM204 S5000\n"}

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