Improving the MMU2 by changing the orange PTFE tube
The orange PTFE tube has been discussed several times in this forum but I think it deserves it’s own thread now.
Long story short I changed the orange PTFE tube and the 5 small ones in the MMU2 unit with cheap ones of ebay with 2.5 inner diameter (and translucent).
My unit works now waaaay better. In the past I always had to optimize the ramming settings for less stringing and tips with smaller diameter. Since I can now focus on the strings it is a lot easier to find the right settings.
Re: Improving the MMU2 by changing the orange PTFE tube
Agree.
Things I changed:
1. The long tube (orange) to 4/2.5 size tube (transparent is good for trouble shooting too)
2.The short tube in the extruder filament sensor cover to 4/2.5, no other hardware change there.
3. The upper tube connector (festo) changed to a wider bore one because I found that it is narrow and the metal edge is sharp. Now the PTFE tube can pass through completely through the connector to be in direct contact with the selector surface.
4. Loosen the bondtech gear tension a bit so that the filament can be pushed into it easier, making less grinding of the filament inside the MMU.
Principle: all bottlenecks has to be wider and smoother. The above steps make obvious improvement.
Things to do:
1. add springs to the screws of the front cover of the selector ?
2. dial in slicer settings.....
Re: Improving the MMU2 by changing the orange PTFE tube
4. Loosen the bondtech gear tension a bit so that the filament can be pushed into it easier, making less grinding of the filament inside the MMU.
That seems to be my last problem. Getting rid of grinding. Every 20-30 hours I have to clean the unit from all the small filament pieces. Occasionally I also have to check the two M3 screws in the idler body because they get unscrewed over time.
Re: Improving the MMU2 by changing the orange PTFE tube
4. Loosen the bondtech gear tension a bit so that the filament can be pushed into it easier, making less grinding of the filament inside the MMU.
That seems to be my last problem. Getting rid of grinding. Every 20-30 hours I have to clean the unit from all the small filament pieces. Occasionally I also have to check the two M3 screws in the idler body because they get unscrewed over time.
With the adjustments I mentioned, now I get much less filament dust though not completely clean.
The latest firmware also help I think. As far as I understand, it will disable the extruder motor so that the bondtech gear are free to turn when the filament hit the point.
The tension screws holding the bondtech gear together should be set loose enough that you can observe the trap door open up when the filament hit the gear.
To further decrease grinding , i am considering adding spring to the front panel cover of the selector which acts as a buffer during loading sequence. I just have to find some springs and screws....
Re: Improving the MMU2 by changing the orange PTFE tube
.....
1. add springs to the screws of the front cover of the selector ?
.....
I think thats a must have for reliability
Re: Improving the MMU2 by changing the orange PTFE tube
I ordered some extra springs from prusa, but they seem to strong. In general it seems to me that this grinding problem can be solved with the motor driver settings.
Re: Improving the MMU2 by changing the orange PTFE tube
I ordered some extra springs from prusa, but they seem to strong. In general it seems to me that this grinding problem can be solved with the motor driver settings.
Have you tried using springs from ball pens ? As far as I remember, the one invented it use springs from ball pens.
Re: Improving the MMU2 by changing the orange PTFE tube
I ordered some extra springs from prusa, but they seem to strong. In general it seems to me that this grinding problem can be solved with the motor driver settings.
Have you tried using springs from ball pens ? As far as I remember, the one invented it use springs from ball pens.
I refuse to use springs from pens on this highly sophisticated 3d printing machine 😀
Re: Improving the MMU2 by changing the orange PTFE tube
Where did you get the 2.5x4 tubes? When searching Amazon and different local vendors (Germany) I can only find 2x3 and 2x4 tubes. I would prefer ordering locally instead of using something like Aliexpress if I can avoid it (long delivery times..).
Re: Improving the MMU2 by changing the orange PTFE tube
Where did you get the 2.5x4 tubes? When searching Amazon and different local vendors (Germany) I can only find 2x3 and 2x4 tubes. I would prefer ordering locally instead of using something like Aliexpress if I can avoid it (long delivery times..).
Re: Improving the MMU2 by changing the orange PTFE tube
Where did you get the 2.5x4 tubes? When searching Amazon and different local vendors (Germany) I can only find 2x3 and 2x4 tubes. I would prefer ordering locally instead of using something like Aliexpress if I can avoid it (long delivery times..).
That was quick 😮 And apparently I am also blind. Thanks a lot!
Re: Improving the MMU2 by changing the orange PTFE tube
Where did you get the 2.5x4 tubes? When searching Amazon and different local vendors (Germany) I can only find 2x3 and 2x4 tubes. I would prefer ordering locally instead of using something like Aliexpress if I can avoid it (long delivery times..).
That was quick 😮 And apparently I am also blind. Thanks a lot!
Btw. the festos have an inner diameter of about 2.3 mm. I used a 2.5 mm drill to increase the festo id.
Re: Improving the MMU2 by changing the orange PTFE tube
I have been looking in the US for 4mm x 2.5mm PTFE tubing and it just doesn't exist here. Has anyone in the US found this anywhere?
Re: Improving the MMU2 by changing the orange PTFE tube
I think this PTFE tube with 2.5mm id is the way to go for me. I ordered one and will see if it solves my problem. Thank you.
My youtube channel about the Prusa I3 MK2 https://www.youtube.com/channel/UCz-zQZcKcvEDdd9C9hOKYWg
Re: Improving the MMU2 by changing the orange PTFE tube
I have been looking in the US for 4mm x 2.5mm PTFE tubing and it just doesn't exist here. Has anyone in the US found this anywhere?
You can see a lot in Amazon just like this one:
DealMux 2.5mm x 4mm PTFE Tubing Tube Pipe 1 Meter 3.3Ft for 3D Printer RepRap https://www.amazon.com/dp/B072SKTRV1/ref=cm_sw_r_cp_api_i_74UgCbEJ0ZJE9
Capricorn also carry 4x2.5 tube(blue). I wish they have orange
Re: Improving the MMU2 by changing the orange PTFE tube
I have been looking in the US for 4mm x 2.5mm PTFE tubing and it just doesn't exist here. Has anyone in the US found this anywhere?
You can see a lot in Amazon just like this one:
DealMux 2.5mm x 4mm PTFE Tubing Tube Pipe 1 Meter 3.3Ft for 3D Printer RepRap https://www.amazon.com/dp/B072SKTRV1/ref=cm_sw_r_cp_api_i_74UgCbEJ0ZJE9
Capricorn also carry 4x2.5 tube(blue). I wish they have orange
Every 4x2.5 tube on Amazon ships from China. I don't want to wait 6 weeks.
Capricorn tubes are 4x2 as stated on their website and in their shop.
Thanks, anyway. I guess I'll just need to order some from Europe. The shipping will be expensive but I can have it in a week.
Re: Improving the MMU2 by changing the orange PTFE tube
Sorry, I checked again and found no 4x2.5 for Capricorn. Probably I mixed up because I was searching for orange 2.5mm at Aliexpress, China Amazon equivalent.
Re: Improving the MMU2 by changing the orange PTFE tube
I bought it from http://a.co/d/cdIlt25 . It says white, but it is translucent enough so that I can see filament through it (even white filament).
Re: Improving the MMU2 by changing the orange PTFE tube
I got this one on Amazon with prime shipping: https://www.amazon.com/gp/product/B07CBR9M6J/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
Re: Improving the MMU2 by changing the orange PTFE tube
I got this one on Amazon with prime shipping: https://www.amazon.com/gp/product/B07CBR9M6J/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
I bought it from http://a.co/d/cdIlt25 . It says white, but it is translucent enough so that I can see filament through it (even white filament).
Funny, I bought some from a UK vendor on Ebay and then saw this. Ordered this as well. Can't have too much PTFE tubing around. I did every search imaginable on Amazon and this never showed up.