Back at it with a custom MP3DP

I’ve built a couple of MP3DPs for friends and family but this time around I’m building myself a fancy one with duel bowden extruders, almost done and just to excited to just post this awesome picture of the two bowden tubes running into my mounting system and my auto bed leveler and everything just looks so awesome and tests so far are pretty cool!


That is very neat. I’ve never tried bowden. I saw one of tech2cs early videos where he replaced the direct drive on a prusa clone with a bowden and swore the quality improvement was huge. I’ve heard others complain about things like retraction problems. I’ve never tried flex filament, so maybe I should try it on my printer…

So far I haven’t had a lot of problems, the bowden tubes are pretty short so that probably helps a lot, you do have to tweak settings to get it to work right because its definitely different then direct drive but the benefits are there for sure!


Also this thing looks amazing, like something from a cyberpunk setting haha


1 Like

What was that movie where time travellers pulled people out of crashing airplanes? It reminds me of that.

Definiteky extra point for style.

1 Like

for anyone interested in the design of the mount:

all operational after a lot of fun with a shorting out heated bed (ate two ramps boards :|) but now we are up and running! (leds were required)

That is some high tech fancy modding. Super cool. I always have big intentions but never just get to it, as I get closer to the finish line I just want to use it… I don’t make a good modder…

That is quite a KITT. Looks pretty awesome. How well does it print?

Man I was gunna say that but was worried I would sound too old!

I am not sure you have looked at it yet but Marlin has all kinds of cool led integration built in now. Fade when heating to temp and flash when ready.

Haven’t you heard? Nostalgia from the 80s is so popular, kids born in the 2000s are making references.

That’s the first time I clicked on ‘download all files’ and it didn’t just give me a zip. I guess I’ll do the zip myself, since it seems to let me download the individual STLs just fine. I’ve got a Chimera hot end that’s just been gathering dust that wouldn’t be tough to adapt to this, and I’ve been running Bowden on my MP3DP for years now.

So… What about part fans? :slight_smile:

It still prints pretty bad, maybe you guys can help, I keep getting hashing patterns in the tops and bottoms of things, the walls are solid, but anytime its solid filling there is spaces. I tried a lot of things, raising the heat helped some but its still not quite right. picture of the problem below.

I tried raising the feedrate, tightening the motor spring, lucubrating the bowden tube, slowing it down to a crawl, raising the heat, all of which helped slightly but it seems like a bigger issue is causing the real problem.


I’m actually using octoprint to control the neopixels, they become a progress bar while printing, change colors based on states, like heating and leveling or idle [the knightrider animation ;)]

AH-ha! I figured it out, needed even more heat, and better retraction settings to deal with the side effects of that more heat!


edit: no wait…still kinda gapy… but def better.

Have you calibrated the extruder at your new temps? It looks like it is definitely under extruding.

Are your temps crazy high? Maybe you have the wrong thermistor table in the firmware?

I don’t follow this exactly, but I do use this guide as a reference when I’m setting up my machine, just to make sure I’ve thought everything through:’s_Calibration_Guide#Nozzle_Temperature

The parts on calibrating the temperature and esteps are pretty close to my methods.

Seems the problem is the thermistor, as proved by checking it with a thermometer laser. Trying to figure out what the thermistor number is for this model, that will probably solve everything I’d assume haha

So, adjusting the thermistor helped a lot, no longer a mesh see through print, but the top still has that hash pattern on it. suspect this is some secondary issue.

Nozzle diameter or extrusion width could be set wrong, if the model dimensions are coming out relatively correct.

thats what I was thinking; but the nozzle diameter is set correctly. the filament diameter is correct as well.


Its almost like the layers aren’t being smashed together like normal and are sitting on top of each other, I tried adjusting layer thickness (I know this probably wouldn’t fix it) but it had zero effect.

Can you post another pic or a few? Did you calibrate the esteps?

The bottom might be squished (bed levelling issue) and you’re still under extruding. They should behave in a similar way.

Ryan’s suggest about nozzle size is a good one too. You don’t have the slicer set to 3mm filament, do you?