Bowden setups

Hi when I first got into reprap there was only 1.75 Bowden setups and no 3mm. As I remember it was more difficult. My question is what's changed as I'm building a kossel with a Bowden and would like 3mm as I have a lot of 3mm material will I run into any difficulties i Will eventually move over to 1.75 and I know I will have to calibrate again but I was hoping to calibrate with the 3mm first to use up my 3mm filament

Edited 1 time(s). Last edit at 03/07/2016 01:03PM by chris33.

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Check my rubbish blog for my prusa i3

up and running
[3dimetech.blogspot.co.uk]

My Prusa i3 used to use 3mm filament, originally with a direct drive. The X carriage used to bang around a bit due to the weight, so I tried 3mm bowden for a while. It worked reasonably well, but I could never get the quality I wanted so I went back to direct drive. Just recently I converted it to 1.75mm to match my CoreXY machine so that I'd only need to stock 1 size - but it's still direct drive (I modified the original extruder).

My CoreXY is 1.75mm bowden, but I'm still not getting the quality I desire, so I think I'll be moving that one over to direct drive as well, before too long.

I had a pgl35 direct on my i3 moved to a flexidrive to lighten the carriage, I will probably end up with the flexidrive on the delta I'm building but I have not designed a effector to fit it so sticking with Bowden for the delta build

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Check my rubbish blog for my prusa i3

up and running
[3dimetech.blogspot.co.uk]

If you get your filament locally they would probably trade your 3mm for 1.75. Mine did. I also gave up on Bowden. It just wasn't working and constantly stripped the filament.

I've tried various Bowden setups and unless the tube is very short i.e. 10cm like on a delta flying extruder it has a big impact on filament control, the tube can't be too tight as there is always some friction, and the filament can stretch/compress as its extruded/retracted.

Direct drive (or flexible drive such as flex3drive) will always give more precise filament control. Perhaps some type of filament movement sensor placed near the hot end feeding back to the extruder motor would enable bowden to be more precisely controlled??

As for 1.75mm versus 3mm, just for the fact that 1.75mm runs off the spool more smoothly, and requires less force to drive it into the hotend, it has to be the better choice.

Edited 1 time(s). Last edit at 03/11/2016 04:40AM by DjDemonD.