When does Zhop really make a difference?  

Re: When does Zhop really make a difference?

With Zhop you don't get scars on top solid layers.

Re: When does Zhop really make a difference?

Z hop also helps where you have tall narrow (tower like )features on your model. helps to prevent the extruder displacing the existing tower layers when the extruder attempts to put down the next layer.

regards Joan

Re: When does Zhop really make a difference?

Cool, so if I want the best print quality then Zhop should be used.

Do others find printing w/o Zhop faster and quieter for the following reasons?

- Less moves to lay down the same amount of filament
- Less vibrations from the z-motors jumping around

Re: When does Zhop really make a difference?

yes, using z-hop helps to avoid the problems mentioned by david.t2 and joan.t.
that's why i like to use z-hop very often.
😛

but if you want to use the color print app, you'll probably run into severe problems because the app tries to detect the beginning of the layer where your color separation height appears in the gcode. to do so, the app analyzes the file and looks where the hotend is set to the height of the desired layer for the color change.
with z-hop this may occur several times instead of once, so you might end up with a gcode file that contains 100 instead of a single M600 command for the favoured layer break.
👿

i ran into the problem with my celtic cross print (see the hall of fame branch at this forum). fortunately i didn't try to print the gcode provided by the color print app and added the M600 commands manually (with an editor) at the correct places inside the gcode.

Re: When does Zhop really make a difference?

added the M600 commands manually (with an editor) at the correct places inside the gcode.

Be aware that the correct place for an M600 command is usually between a retract and a prime command; you will also have to remove the prime command line.

Peter

Re: When does Zhop really make a difference?

Do others find printing w/o Zhop faster and quieter for the following reasons?

- Less moves to lay down the same amount of filament
- Less vibrations from the z-motors jumping around
Faster - yes (well, also depends on amount of Lift Z), quieter - no.

Re: When does Zhop really make a difference?

Why not quieter? Z hops are the second most noisy thing on the printer once you've silenced all the rest (the first being the nozzle fan). Anyway, i find z-hop very useful to avoid scratches on top layer and other problems during difficult prints.

Re: When does Zhop really make a difference?

...
Be aware that the correct place for an M600 command is usually between a retract and a prime command; you will also have to remove the prime command line.

inserted it here, got no problem with it:G1 X136.330 Y32.962 F1920
G1 E-0.8000 F1800
M600
M204 S1200
G1 X136.788 Y32.907 F4800
G1 Z5.298 F1002
G1 E0.8000 F1800
G1 X133.774 Y87.719 E3.0811 F2400

do you mean that the G1 E0.8000 F1800 should have been removed ?

Re: When does Zhop really make a difference?

Why not quieter?
Because I can't hear any difference. My printer is quiet enough both with and without Zhopping.

Re: When does Zhop really make a difference?

do you mean that the G1 E0.8000 F1800 should have been removed ?

Yes, that will extrude a small blob immediately after the colour change. On some prints, it can make the outcome a little less "clean" but for most it is not noticeable.

Peter

Re: When does Zhop really make a difference?

Sorry if this is a dump question but where do I enable/disable z-hop in Slic3r? I didn't see it under retraction

Re: When does Zhop really make a difference?

Sorry if this is a dump question but where do I enable/disable z-hop in Slic3r? I didn't see it under retraction

Printer Settings/Extruder/Retraction/Lift Z

Peter

Re: When does Zhop really make a difference?

Oh so Z Hop is the same as Lift Z? Why not just call it that?