What hot-end/extruder

I don’t have a MP3DP, but I have a Prusa-clone.

I think the stepper motor for the extruder may have gone out on my MK8 hotend. I’m trying to decide if now is a good time to upgrade to a different hot-end/extruder.

I typically only print PLA and ABS, but would like to do PETG and some of the flexible filaments.

What would ya’ll recommend?

I haven’t used a ton of hotend/extruders but if you like flexible filaments direct drives are the best, speed you want a bowden. Other than that you kind of can’t go wrong.

PETG prints at lower /similar temps to ABS but with a lower bed temp not actually considered a high temp filament, I highly suggest you use this instead of ABS unless you need to vapor smooth.

You can pretty easily replace your stepper and sort of upgrade your extruder at the same time, depending on which extruder you have. Using the MK8 cheapy and the microswiss throat I have a killer combo very on par with the titan aero, the titan has the benefit of being a little lighter. That is why I carry all those parts though I use them and prefer them. As my PTFE liners failed I replaced all the throats with the microswiss and have not looked back. Now the only thing that seems to happen is a bearing will go out once and a while.

I have the MK8 on mine now. I thought the Micro-swiss throat was for the MK10?

If there’s one for the MK8 that is all-metal, then that would pique my interest.

Thanks. I found it a few minutes after posting my update.

I have some new cables coming in now. I remembered that the last time this happened it was just a broken stepper cable. If everything still works after replacing the cable, then I’ll look at getting the new hotend.

Make sure to secure the cables to the moving X carriage in some way or you will burn through a bunch of things that way. I had an extruder stepper die the same exact way, a single zip tie later and no failures since.

I got the printer running again last night. During troubleshooting I kept replacing drivers only to finally remember I configured the firmware to only allow the extruder to turn if the hotend was on… Doh.

I’m pretty sure the problem was the cable. Luckily the new cables are longer than the old one, so I’ll be able to wrap it in the cable wrap that the rest of the cables are in.

I ordered the all-metal hotend for the MK8. Can’t wait to play with some of the other filaments.

Dumb noobie question…if a direct drive is best for flexible filaments and a Bowden is best for speed, why hasn’t someone built a direct drive Bowden?..or am I still too new to understand? lol

Direct drive puts the extruder directly on the hot end, a bowden puts it at the end of the tube, so only the hot end is moving around. Closest thing to a direct drive bowden would be the zesty nimble.

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Thanks Barry, I understand the physical difference between the two…what I guess I’m missing is the advantage/disadvantage aspect…

For example, can flexible filaments not be used with a remote extruder system?

They can be used with the zesty. The problem is trying to push a cooked spaghetti noodle through a silly straw. Direct drives work because they’re pulling it through. Semiflex filament sometimes works through a bowden, as long as it’s not too long. The really flexible stuff just won’t work.

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What Barry said…

Flexible filament doesn’t work too well through a Bowden because it bunches up instead of being pushed through the tube.

The reason Bowden setups can run faster is because there’s less mass on the gantry. The hotend can be physically moved around faster than a heavy direct drive extruder on the same mount.

I did end up getting my all-metal hotend running on the printer. Ended up having to modify quite a bit of the mount to make everything work. I still can’t seem to get PetG to print, which was my reason for switching to the all metal, but ABS and PLA are both printing quite well again.

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Thanks guys, I’m in the process of building a machine of my own design and am still deciding on head components…the frame is nearing completion.

When completed, it will be convertible between printing, routing/engraving, and laser engraving with a 1 cubic foot work area capacity. So far I’ve decided to try the DeWalt 660 as a spindle as it seems to be the best “bang for the buck” but still researching printer components and laser modules.

It will be used mainly as a toy to make things for myself with little, if any, commercial duty… although I’m not ruling out the occasional job for pay to feed my hobby. I’m hoping to be able to laser cut 1/8 craft plywood and route/engrave wood, plastics and aluminum.

Thanks in advance for any advice or suggestions…