25mm³/s with stock v6 || 26mm³/s with volcano  

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

Your rate for the E3D V6 with 0.4mm nozzle sounds about right. I'm able to get 45mm^3/s+ out of a stock E3D V6 with 0.6mm brass nozzle printing PETG, so the larger nozzle and reduced back pressure improves throughput considerably. I did find that the Prusa Mk3 extruder tops out at about 70mm^3/s with a 3D Solex Matchless 0.6mm nozzle making meaningful hotend/nozzle readings impossible beyond that.

Not sure why you're not getting better rates through the Volcano, though on a separate printer (Artillery Sidewinder X1) with a Volcano mounted, I can get 80mm^3/s+ with a 1.0mm nozzle printing PETG. 

My understanding from Team Prusa is that the Max volumetric speed settings are set low on PETG to ensure good infill quality, so these maximums may not be ideal for print quality. I haven't done any testing on that aspect yet.

Details here.

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

@bobstro

I just ran your testing method with PETG, even at 295°C! (Maybe I am just already going to high?, also tried 285, didn't work out better) and it started slightly clicking at around 850, so I settled with 800. 800/60 = 13.33.        13.33 * pi * 0.825 ^ (2) = 28.439, so pretty much as my results are...

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

Could it be that my motor is not working properly? The motor was overheating everytime last year which is why I had to put a fan on it, maybe it was just damaged to begin with?

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

Posted by: @zunzulla

Could it be that my motor is not working properly? The motor was overheating everytime last year which is why I had to put a fan on it, maybe it was just damaged to begin with?

I suppose that could be a problem. Try a larger nozzle with the V6 and see if you can get higher.

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

@bobstro

Aight so this took me a while. I couldn't do any print tests so far because I am waiting for glue to dry on a part I broke ^^" 

I build a pulleybox ( https://www.thingiverse.com/thing:3714978 ) with a 1:3 gear ratio. I am using a completely new .8 nozzle on the volcano and I am now slightly above the 26mm³/s, around 28mm³/s. Not 100% sure because I didn't see a print result.

With this pulleybox I can clearly hear that the clicking is not coming from the motor but rather from the bondtech gears. I tried tightening them and loosening, doesn't change the sound.

I've already spend too much time on this tbh :'D

Edit: If there is no other suggestion I will buy a new motor, I don't have a v6 on me anymore ^^

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

Cleaned the bondtech gears for a while, didn't help also .-. Going to check the PTFE at some point before buying the new motor

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

I changed the motor current to 950mA and I am finally able to hit the 40mm³/s mark without clicking ! @bobstro though, I've heard people managed to go even further. I am now using a high current on those motors + 1:3 gear... now it's either the motor, or the PTFE is acting up 

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

Interesting. I wouldn't have expected the motor current to matter since it sounded like the extruder feed gears were slipping, but glad you're getting better results. So you're at 40mm^3/s with a 0.8mm nozzle with PETG? That's about on par with what I am getting with a Volcano with a 0.8mm nozzle mounted and printing PETG on my Sidewinder (40.08mm^3/s), so it sounds like you're getting beyond what the stock extruder can deliver. 

I'm having fun following the different discussions on the 2 different printers. On the Prusa forums, the push seems to be on more hotend capacity with some emphasis on a geared extruder over a dual-drive extruder. On the Sidewinder forums, the push is on dual-drive extruder over the stock geared E3D Titan Aero clone. A Bondtech BMG extruder with geared dual-drive feed seems to be the sweet spot.

I was originally more concerned about hotend throughput, but I'm running into possible issues with the longer Volcano block causing wobbling and wall irregularities on the Sidewinder (possibly). I am able to get roughly the same range with the V6 hotend with a 3D Solex Matchless 0.8mm nozzle mounted. It was at 70mm^3/s that I seemed to max out the Prusa extruder. I'm leaning more towards a higher-capacity extruder atop a V6 hotend with a 3D Solex nozzle as my ultimate goal. Not in a big hurry though, so this is more hobbyist musing!

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

@bobstro I noticed the motor is becoming fairly warm/hot on the outside, perhaps this is the main reason Prusa capped it at a low amperage (I think 550mA?) Though using the pulleybox I am not transfering the heat to the incoming filament.

I am thinking my motor does not need to be replaced now since after your latest message I am very pleased with the results. Due to my "cleaning method" I have probably damaged some components permanently a while ago (using a propane torch, not the smartest idea). I am going to replace most of the extruder with some proper materials (nickel plated copper nozzle and heat block, titanium heatbreak, capricorn PTFE tubing) and perhaps I can get even higher numbers. I am not anticipating too much 🙂

Reason for this is that I achieve worse results with my 1.2mm (older, 30mm³/s) nozzle than my .8mm (never used, new, 40mm³/s) one. I have noticed that there seems to be some carbon based material (not filament, coal perhaps) on the inner walls of the 1.2m nozzle :s I'll report back with the results, it will take some time till then! Thanks for all the help 

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

I'm hoping that by documenting this, we're helping others out. I saw a lot of early efforts spend focused on "speed" with very little discussion on hotend capacity and throughput. I find that understanding those aspects of the printer really allow me to maximize production. Not that I need to most of the time, mind you, but it was gratifying bumping up production rates for the COVID printing push.

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

Just a brief update: I upgraded the E3D volcano heatblock from aluminium to copper, reaching an MVS of around 50 with Extrudr PETG filament. But this is the absolute maximum and completely useless to print with (obviously ^^). I think the last test would be swapping the extruder motor out with something a little stronger, might give it a shot when my salary rolls in 🙂

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

At a feed rate of roughly 1700mm/m (28.3mm/s), I seemed to top out the Prusa extruder with PETG at 250C through a nickel-plated copper V6 hotend with a 3D Solex 0.6mm nozzle (~70mm^3/s MVS). With clones of an E3D Titan Aero extruder through a nickel-plated copper Volcano hotend on my Sidewinder printer, I seem to top out at 2300mm/m with PETG through a 1mm nozzle (92mm^3/s MVS). You may be able to bump it up a bit higher on the Mk3 with a new extruder, but I'm not sure it's worth the risk of introducing problems if you're otherwise happy with your Mk3 setup. I assume you modified your Mk3 firmware to accommodate the Volcano?

I should try printing something at these top speeds just to see if it works at all. PETG at 250C seems to flow well. Not sure the results will be anything usable though. Fun to try though.

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

@bobstro

You Sir keep making me poor. I-don't-have-my-salary-yet! 😀 

The only thing I changed in the firmware was the e-steps for the 3:1 gear ratio and the max. z height due to volcano. Was there anything else I had to change? I hope not .-.

I did at some point increase the current going to the extruder motor from ~500mA to 900mA, it worked for testing the MVS but when trying to print for a few minutes the printer couldn't get after a certain point on the benchy. Upon changing it back it works again, I assume the PSU couldn't handle it? 

I am looking forward to swapping the extruder motor out, since it keeps getting really hot (60°C+) even with the current settings back to normal, perhaps I will get an RSP-320-24 power supply along the way. As already mentioned a few months ago, it might be that the motor is just not working optimal under bigger loads

70mm/s³ on a v6 sounds crazy, I could never get close to that with my volcano...

RE: 25mm³/s with stock v6 || 26mm³/s with volcano

Posted by: @zunzulla

[...] The only thing I changed in the firmware was the e-steps for the 3:1 gear ratio and the max. z height due to volcano. Was there anything else I had to change? I hope not .-.

I'm curious myself. I haven't done firmware changes to my Mk3, but am happily tweaking Marlin 2.0 on my Sidewinder. I may update the Mk3 someday, but I'm not in a big rush to do so.

[...] 70mm/s³ on a v6 sounds crazy, I could never get close to that with my volcano...

That's more of a theoretical limit than practical. I wouldn't expect print to fare very well. I was driven into that last round of testing by the COVID PPE printing response. I wanted to reduce print times as much as possible. My main finding was that I could use 25-32mm^3/s with PETG @ 250C through a 0.6mm or larger nozzle without problems and significantly reduce print times. It was a balancing act, and I still had to watch out for things like layer heights on overhangs. These prints didn't require supports or infill, so a lot of typical print challenges weren't a problem.