Out of curiosity, what print speeds are people using on the H2Cs? I know that each filament brand/type can have different speeds but let’s take PLA or PETG for an example.
I am not asking what speeds should I be printing at but rather what is the machine capable of. The machine has a pretty heavy toolhead which limits the speed but at the same time, it moves pretty fast during travel moves.
The firmware max travel speed is 1,000 mm/s, with acceleration of 20,000 mm/s/s.
It will do that on travel moves if the conditions are right.
Thanks. I didn’t know that.
However, my curiosity is about printing speeds, not travel.
You’ve asked an unanswerable question. I’ll explain.
The ultimate limiting capacity of the extruder is the heating element that is melting filament - it can produce only so much heat for the job, which is a function of the voltage it’s getting and the resistance of the heating element.
The next limitation is heat transfer rate. How fast does heat get transferred from the heater and into the filament? That depends on the hotend. Regular hotends transfer heat less efficiently, high flow hotends transfer it more efficiently. Different nozzle materials impact how efficiently heat is transfered to the melt zone.
How fast does filament take on the heat? Every filament is different, and in some cases different colors within a single brand can have different melt performances due to the colorants present. It’s not as simple as PLA or PETG. Basic is different from high speed is different from some of the other fancy formulations.
How fast can the filament get out of the nozzle? Assuming the extruder gear can push filament as fast as it needs to and assuming all the melt requirements are met, it’s down to how much the nozzle can flow. What’s your nozzle diameter? You’ll never be able to move fast enough with a 0.2mm nozzle to go faster than the heating system can sustain. On the other hand, a 0.8mm nozzle can absolutely allow extrusions fast enough to outstrip the heater for some filaments (but not for others). I mean…if someone is a total lunatic I have to wonder if a hotend can be operated without the hotend cooling fan just to make more use of available heat to melt filament.
The other dimension is layer height - if the extrusion opening is the nozzle diameter AND the height to the previous layer, a very thin layer may reduce the 0.8mm nozzle’s ability to flow material to the point where it can’t outdo the heater - but then again, if you crank the 0.2mm nozzle high enough over the last layer and the filament melts easily enough…who knows?
Some deranged individual posted on here saying they’re using a 0.2mm nozzle at some bonkers speed, I just shook my head and moved on.
Here’s a speed test. Have fun!
I am sorry if I seemed naive/uneducated and thank for the detailed information. I was aware of a lot of the details. I was just asking what people are actually using.
What’s interesting is that calibrating max volumetric speed doesn’t actually involve printing anything 
( Determining Maximum Volumetric Flow Rate | Ellis’ Print Tuning Guide ). Just another method…
That Ellis website method is somewhat outdated, and comes from a time before printing the race track was developed. I’m sure it still works and has advocates, and maybe it might give a better result for some small fraction of the community, but the race track print is just easier to use. One print, one setting, and it’s done. As opposed to performing some arcane ritual repeatedly.
EDIT My personal opinion is that max print doesn’t really matter because the machine will never reach it unless your whole model is giant square (going around corners slows the print head), and reliability and quality are more important to me than time. I therefore leave the machines on the default setting, then turn down the volumetric flow to match the filament used if I notice any problems occurting.