Cf petg printing on the ender 5 plus

hello all. im trying to print carbon fiber petg on my e5plus
i have a .6 nozzle and heat is set to 250 on the head, im getting skipping at the extruder gear(bowden) due to the filament being so stiff and the gears not gripping the filament.
i think this is due to the shape of the gear as its a flat gear trying to grip filament which is not flat, im looking at upgrading my extruder and want to know if this will mount to my printer and be in line with filament sensor. and or if you see any issues with my choice

Bondtech BMG Extruder Mirrored (Left Hand) 1.75mm | Bondtech - 3D Printing Canada

thank you in advance to who ever takes the time to help me before i order.

Have you tried increasing the tension on your existing exturder, so it digs in a little more?

Also, are you sure you aren’t trying to print too fast? This kind of problem also occurs when a particular type of filament takes longer to melt. You end up pushing the filament in and the end hits the nozzle before the filament has melted. Try slowing down considerably and see if that helps. If it’s truly a speed issue, a new extruder won’t help you.

the tension is maxed out. im only at 40mm/sec so im not fast… i think its due to the gear being flat and filament hard…

With a .6 you might need a higher hot end temp and slower print speeds for the extra material flow. Carbon can be a pain, it eats brass nozzles. I know everyone suggests hardened steel but IF some of your issue is heat related the hardened steel will make that worse. I have been using Stainless not as bad heat issues but it lasts better than brass.

Temps are easy to fiddle with, you still may need a bond tech anyway.

bond tech is on the way, thanks guys.
for now, i mitigated the issue by doing smaller layer heights and 40mm/sec the smaller layer height is pumping out way less plastic and allowing the plastic to melt a tiny bit better. maybe ill look at getting an all metal hot end as well so i can go higher the 250c

if you’re printing at 250 on a stock under five plus you’re definitely going to get heat creep. that’s too hot for a stock machine, plus if it’s our house brand petg CF I print that stuff at 230 it comes out beautifully you also need to do a hollow cube with one outline to measure your extrusion with line to make sure it falls in between what you are calling for.

for example .6 nozzle with .6 extrusion with line when you print the hollow cube with only one outline and you measure your wall it should fall between.6 and .65 if it’s any thicker you need to lower your extrusion multiplier/flow rate.

also if you are planning on printing materials like this I highly recommend switching to a direct drive unit I personally prefer the micro Swiss direct drive due to how easy it is to install and maintain you could also put Bond Tech there’s a few different extruders out there my favorite right now is the micro Swiss direct drive. I’m also loving the orbiter style direct drives with the little mini motor on the back.

my extrusion is set that way already, im not experiencing any heat creep, i plan on upgrading to the microswiss all metal hot end, but plan to keep my setup bowden for now. im getting amazing prints as of right now, but am limited to lower layer height lines for now as it gives time for my plastic to melt till i get my bond tech.

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best suggestion is to go with an all metal hot end and the dual gear extruder, Micro Swiss does have a kit with both, I would even step up to the .8 while dialing it it.

Hope this helps
Jason H