Print at one speed for first layer, then a different speed for the rest?
Is this configurable in Prusa Slicer or otherwise? I've found that my prints go a lot better when I do the first layer at 75% or even 50% speed, and the rest of the print can usually be done at higher than 100%. First layer adhesion and appearance seem to be much better. Thanks so much for your help if this is possible!
RE: Print at one speed for first layer, then a different speed for the rest?
Yes it’s a standard setting, you have to be in advanced mode but you can set all the different perimeter speeds including first layer.
RE: Print at one speed for first layer, then a different speed for the rest?
Just to add to what @neophyl posted, take a look at Print Settings->Speed->Modifiers->First layer speed in Advanced or Expert (recommended) mode.
RE: Print at one speed for first layer, then a different speed for the rest?
So that setting didn't seem to do anything... my printer was set at 200%, which seems to work fine for my print on the upper layers because it has a lot of straight lines in it, so I changed the "First layer speed" setting in Prusa slicer to 75% and created a new gcode. But when I started the new gcode, the printer started off on the first layer like a bat out of hell at 200%. Is "75%" the wrong syntax, should I enter it as "0.75"? Thank you!
RE: Print at one speed for first layer, then a different speed for the rest?
So that setting didn't seem to do anything... my printer was set at 200%, which seems to work fine for my print on the upper layers because it has a lot of straight lines in it, so I changed the "First layer speed" setting in Prusa slicer to 75% and created a new gcode. But when I started the new gcode, the printer started off on the first layer like a bat out of hell at 200%. Is "75%" the wrong syntax, should I enter it as "0.75"? Thank you!
If you set it to 75, it will use 75mm/s (which is awfully fast for a 1st layer). 75% will set it to 75% of whatever speed is used for the feature being printed (those in the box above that setting). I use 25mm/s. It's slower, but better to have a good 1st layer that supports the entire print than a fast one that fails 20 hours into a long print and wastes all that time and filament.
Be aware that if you're dialing speeds up using that front knob, it can be a bit misleading. You're increasing printer movement rates, but you're still subject to the physics affecting the printer. The printer only accelerates and moves so fast, and by over-riding the slicer settings, you're basically entering unknown territory speed-wise and any of the safeguards build into the slicer are thrown away. You are far better off changing your speeds in your slicer, developing a separate high speed profile there so you'll have control over what is actually printed. If you're using PrusaSlicer, it will also respect the Maximum volumetric speed setting which corresponds to the maximum amount of plastic the E3D V6 hotend can melt and process (advertised at 15mm^3/s, closer to 11.5mm^3/s in practice). Ignore that rate and you're likely to run into extruder skips and jams.
tl;dr: Setting it to 75% probably didn't have much effect because 75% of the speeds you're using are likely already exceeding the hardware limitations.
RE: Print at one speed for first layer, then a different speed for the rest?
@bobstro
Great, great, great information. Thank you for taking the time to explain. I'm exploring a manufacturing use for my printer, so I'm pushing the envelope in terms of speed to maximize output. Since 200% machine speed on the upper units seemed to work fine for extrusion, I doubled all of the print speed settings in Slicer, set the first layer for 30% speed, and left the printer's speed set at 100%. So far, so good. Thank you again for explaining.
RE: Print at one speed for first layer, then a different speed for the rest?
[...] I doubled all of the print speed settings in Slicer, set the first layer for 30% speed, and left the printer's speed set at 100%. So far, so good. Thank you again for explaining.
Slice a part, then spend some time in PrusaSlicer's preview mode. Take a look at the volumetric rate and speed previews. Try changing the Maximum volumetric speed for your filament under Filament Settings->Advanced and watch what it changes. This is a good way to get a handle on what's going on and what settings cause meaningful changes. A lot of people get caught up in speed settings without realizing that the extruder itself puts limits on how fast you can process materials, particularly once you get above 0.40mm nozzles. On small parts, you never get anywhere near those speeds you typically see in print settings due to acceleration and jerk limits. If you're doing production work, you'll want to master these settings for good consistent results. Good luck with it!
RE: Print at one speed for first layer, then a different speed for the rest?
@bobstro
Hi there, thank you for the explanation, its quite strange the inconsistency between what the printer shows from the panel 100% speed vs what slicer shows 20mm/s. Now on Slicer it says: "20" "mm/s or %" this seems to be the default value.
For newies like me, I am understanding that this would be applied by default to any Gcode prepared through Prusa slicer right?
Also, is 20 mm/s translatable into for instance 70% of the speed as shown in the knob? What would be a good speed for most prints to ensure we have a good first layer? And in % ? It would be great if I can have mm/s both on the printer and on slicer o both with % but at least in a way where I can relate to each other.
Thanks for sharing your comments
Fernando
RE: Print at one speed for first layer, then a different speed for the rest?
The % speed shown on the printer is not an indication of the actual print speed. If you set your perimeter speeds to 50mm/s and your infill at 70mm/s for example in slicer, slice and print then the printer will use those speeds for those features with the LCD set to 100%. If you turn the LCD speed setting down to 50% then you are telling your printer to print everything at half speed, so Perimeters would be 25mm/s and infill would be 35mm/s. So its a percentage of the speeds set in the slicer.
Just set the speeds correctly in slicer and dont worry about changing the speeds on the printer. I sometimes use it to speed up a print but only rarely. Its far better to set all your speeds in the slicer to realistic values for the quality of print you need
RE: Print at one speed for first layer, then a different speed for the rest?
@neophyl
Thank you I understand now, but what is the recommended speed for a first layer then 20mm? Is there any reference we can have a look at?
Thanks again for your help
Fernando
RE: Print at one speed for first layer, then a different speed for the rest?
Ideal First layer speed is entirely dependant on your printer and the material you are printing as well as the complexity of the first layer.
If you are using a prusa with smooth sheet that is perfectly clean in, pla, you can lay down a faster first layer with less chance of problems than say if you have a printer with a different surface. Printing a large flat surface like a cube you can go faster than something with lots of small islands or using a lot of support where the print lines are more complex. You could spend time working out the most optimal speeds etc or you could go slow just to be safe. I have mine set to 20mm/s second and never have trouble even with the zigzag used as support base. Then again I keep my sheet clean and have no trouble with adhesion either. Could I go faster, sure. I just think that taking that first layer slow means I always get a good first layer and there's very little risk. YMMV.
Printing is part technical and part art. The best way to learn is to do and see what your particular setup works best at. You could have an identical machine printing the same material and model as someone else but get different results due to the environmental conditions being different. I would say that printing slower than 20mm/s is probably pointless. If you have trouble with the first layer at 20mm/s then look for what the underlying issue is as it probably wont be the speed.
RE: Print at one speed for first layer, then a different speed for the rest?
If I set the speed at %85 in the printer, what is the equivalent speed in Prusaslicer?