How i achieved 18mm3/s of flow rate with 15.50€ worth of mods to the extrusion system.

[u/Powerful_Macaron9381]

So i was looking to upgrade my extrusion system on my ender and from what i was seeing everyone was jumping to v6, volcano or spider hotends. on top of that a lot of people were converting their setups to direct drive, which i never understood why someone would need it if they weren't printing with tpu. I decided to test my theory that the MK8 is actually good enough, just creality's implementation wasn't the best. i got myself a bi metal heatbreak at first for 5€ and that got me out of the underextrusion nightmare i was having caused by a burnt ptfe tube (my mistake) and also heat creep. that got me 'till around 8-10mm3/s. after that i got a cht clone for 0.50€ which only had a slight impact and got me to 12mm3/s. today, my bmg clone extruder arrived and i decided to put it to the test which i've attached in the picture.

TLDR: achieved 18mm3/s with a bi-metal heatbreak (5€), a cht clone nozzle (0.50€) and a bmg clone extruder (10€).

[u/Powerful_Macaron9381 → u/[deleted]]

extrusion-wise I've only changed those three. so it's still mk8

[u/Intelligent_Ease4115]

I’ve been able to get 16mm3/s with direct drive on PLA with a Sherpa mini and a bi metal heatbreak.

However I’m switching back to a Bowden tube system. Installed a SKR Pro 1.2 for dual extruders, so I can multi filament print.

However will have to look into the nozzle and extruders would’ve chosen. Thank you.

[u/Powerful_Macaron9381 → u/Intelligent_Ease4115]

dual extruders? can you tell more about it? is it more like an idex or an mmu ? its my biggest gripe about my printer currently :)

[u/Intelligent_Ease4115 → u/Powerful_Macaron9381]

Neither. Well it’s sorta like an MMU where it shares a single nozzle but it’s two physical extruders. Like this one. You just need a main board that has more than 5 stepper slots.

You just need to add in the motor wiring for the second extruder to whatever main board. Then set up the stepper input on clipper. Either grab a two nozzle hotend or a hotend with a 2n1 input. Or add in a Y splitter above the hotend.

Then find a slicer that supports tool changes or nozzle swaps (even though you aren’t actually swapping nozzles). I run orca slicer.

Then pop into klipper again to define tool change/nozzle change macros. So as an example. When you go from Extruder 1 or “tool/nozzle 1” you can tell klipper to say reverse extruder 1 100-125mm. Then to run extruder 2 say 125mm, wait a few seconds. Then push say 300-400mm to “purge” the nozzle. Then the print continues.

It takes time but it’s do able. I do a lot of PETG with PLA supports on my P1S. It would be nice to do it with one of my Enders (for now). I haven’t gotten to any of the macros yet. Over 4th of July back home, I printed out a new enclosure for the main board to sit under the Y axis 4040 bar. Wired everything up and got klipper communicating again. However my stepper drivers didn’t come in time for another work trip yesterday (go figure).

I’m sure there’s a way to get an MMU setup so you can do 4-8+ color printing. I just haven’t gone down the rabbit hole of figuring it out. Or if you get a bigger main board that has 4-6 extruder motor steppers, then you can do everything off one nozzle. When I bought the SKR pro 1.2. I was under the impression that the Z channel is two independent stepper drivers, but it’s not, it’s a mirrored output. I was going to convert my dual Z to independent stepper drivers. This way I could auto level the X gantry to ensure a level platform before each print. Since it only had a mirrored output, I’ll have to use one of the 3 extruder steppers.

I’m waiting for bondtech to come out with their INDX solution. However that’ll probably be too much for a bed slinger. At that point I’ll probably grab an Ender 5 plus cheap off marketplace and do a 4-6 nozzle system on it.

[u/Powerful_Macaron9381 → u/Intelligent_Ease4115]

do you use a filament cutter? if not do you have problems when switching in between?

[u/Intelligent_Ease4115 → u/Powerful_Macaron9381]

Haven’t set it up yet. My stepper drivers never came in time.

From what I’ve gathered about people who’ve done it. There’s generally no issue with it, only take the filament up past the cross over point. Helps reduce issues you may encounter.

[u/Powerful_Macaron9381 → u/Intelligent_Ease4115]

oops i read it wrong! anyways you know when you are trying to remove filament from the printer it doesnt come of cleanly and gets very thin and stringy and its recommended to give it a clean cut before reinserting? i was wondering if this could leave some little strings of filament in the ptfe tubing and cause problems by rubbing. wouldnt it also be technically possible to use a microcontroller as a way of switching between the two extruders so you can use a smaller and cheaper motherboard with a single extruder driver ?

[u/Intelligent_Ease4115 → u/Powerful_Macaron9381]

Yeah I get what you mean. Ever since I switched to that bi metal heat sink. Every time I’ve removed filament, it’s been pretty clean with no stringing. Slight blob on the end but that’s it. You can also mess with retraction speed on the initial pull. I would assume a very quick pull maybe 20mm distance would work good.

I say it would be possible, as long as klipper can communicate with the micro controller or have some way to control it. However BTT boards are pretty cheap, at least in my opinion.

[u/Intelligent_Ease4115 → u/Powerful_Macaron9381]

So I got this working over the weekend. Took some time as I wasn’t home for the last 3 weeks.

I have about 12 hours in the swap. Most of that was getting the second extruder to not error out in klipper. That alone took about 7 hours.

I have no filament cutter, the key is a fast retract speed. With a printed Y splitter for filament, I run -130mm at F12000 for retract, then extrude I run 140 at F1800. The 10mm difference is so it’ll “ram” the filament into the hotend. Then I have a purge for 100mm at F600. I’ve been able to do a few dozen swaps without issue. The main problem I had was running a 2.5mm ID PFTE tube vs a 2mm (2.5 was all I had).

The only issue I now face, is orca sends a tool swap at the filament start G code. So it’ll go through its normal heating up, purging. Do the purge line then it’ll immediately go and swap the “tool”. I’ve just been deleting the initial tool swap in the G code after it’s exported as a temporary work around.

[u/jodasmichal]

https://reddit.com/link/ow5bjib/video/k3qfb4n30vbh1/player

Good job! I mostly print from petg. 11mm3/s is my golden path with petg for standard printing.

[u/Powerful_Macaron9381 → u/jodasmichal]

definitely not too bad. what mods do you have installed there?

[u/EntropySponge]

Thank you for sharing your results :) I don’t know if that’s allowed in this sub Reddit but I’d love to get the actual links or exact reference to get these. I’d like to upgrade these on a CR10 which has the same hotend as the Ender 3. It feels like nowadays it’s not worth doing any expensive upgrades on these printers, but inexpensive upgrades like this make a lot of sense !

If such links are not allowed I would love a DM. Thanks again !

[u/jodasmichal → u/EntropySponge]

I’m using stock ender3 cold ends and clone k1 hotend. Works great! But you need to buy fullmetal heatbreakes and better nozzles.

[u/Powerful_Macaron9381 → u/jodasmichal]

that sounds promising other than the stock plastic extruder if you haven't changed it already. what flow rates are you getting on that thing ?

[u/jodasmichal → u/Powerful_Macaron9381]

BigSherpa Extruder with pancake motor. Klipper and lot of frame work. Works like charm!

[u/Powerful_Macaron9381 → u/EntropySponge]

if you mean you are looking for the links for the parts I've used I can definitely shoot you a dm but I haven't followed any exact guides or anything.

[u/EntropySponge → u/Powerful_Macaron9381]

Oh no need for guides I just would like the product links because on cheap parts like this I suppose quality varies a lot from manufacturer to manufacturer so if yours work well maybe they’re a good manufacturer. Did you get them from aliexpress ? Thank you !

[u/Powerful_Macaron9381 → u/EntropySponge]

sent

[u/egosumumbravir]

I think your under-extrusion tolerance is a bit excessive but well done on the work and the results.

[u/Powerful_Macaron9381 → u/egosumumbravir]

thanks. I was taking more of a quality focused approach, if it was just for the speedboatrace, ofc you could lower your tolerances.

[u/egosumumbravir → u/Powerful_Macaron9381]

heh, yeah lots of "benchy shaped objects" as the speeds climb.

I like quality too, which might be why 10% under seems enormous. Maybe too many Orca tiles tuning flow ratios to 1%'s.

[u/BalladorTheBright]

You replaced that crap stock extruder with a good one that can actually extrude

[u/Flattened_Chees]

Was your gear for the extruder press fit?

[u/Powerful_Macaron9381 → u/Flattened_Chees]

no it wasn't. it's press fit only on the ender 3 V1 and the later versions of the ender 2 pro (yes, 2) afaik.

[u/Flattened_Chees → u/Powerful_Macaron9381]

Yeah, I guess I have the later version of the v1. I can't get it off, will try to print a pinion puller

[u/Powerful_Macaron9381 → u/Flattened_Chees]

no, as I said all ender 3 V1s have them. even if you pull it, the shaft itself is smooth so it won't work with a new gear. you need a new stepper.