Cooling the feeder

[kris 29]

Hi

Has anybody considered cooling the feeder?

Tried several prints during the weekend. All prints failed fairly early on; at first material flow was OK. After a while every print experience underextrusion that would culminate in 0% material flow. As usual I suspected a clogged nozzle. Cleaned it...several times. Didn't help.

Finally I realized that the PLA filament had been flattened by the feeder. The feeder could still grab on to it, but with the new shape the filament would cause significant friction in the tube. No chance for the feeder to able to push it to the hotend. I had previously notice on my UM2's that the feeder wheel would get very warm because it is directly connected to the stepper motor. In addition, due to the climate we had close to 30°C in the room.

I then put a fan behind one of the printers to help cool the feeder. Problem solved.

I am no considering placing small fans to the rear of the prnter to help keep the feeder/ filament cool.

What do you guys think? Any similar experiences?

Cheers,

Kris

[IRobertI 521]

I haven't done it myself but I've heard of others who had your exact problem and fixed it by adding a small fan back there. I'd say go for it. Especially with the heat wave going on right now it's not a bad idea to help the printer cope.

[francfalco 39]

Same here - i had the feeder wheel 'flatten' the filament before it got into the Bowden tube.

Must have been the v hot weather we had in the UK recently - that won't last but a cooling fan on that feeder stepper motor does sound interesting...

[gr5 2,334]

I wish Ultimaker had provided a layer of insulation between the feeder shaft and the knurled sleeve somehow. They are in netherlands and if the temp reaches 25C they act like they are going to die of the heat, lol. They probably rarely run the machine that hot.

I have had the inside of my machine at 40C but only when printing ABS which doesn't get soft until around 100c.

There was a woman in brazil on the forums who had the same issue at 30C.

[kris 29]

I have purchased two 60mm fans and designed a printable fan mount.

My UM2's are all enclosed with acrylic and I will simple cut out a piece of the acrylic and mount the fan to blow directly onto the feeder. I guess it cannot hurt to cool PLA even below 30C. I have noticed that there is a small deformation of the filament even below that temperature. That causes unnecessary friction in the bowden.

[kris 29]

By the way; does anyone know if I can run an additional fan (12V) from the mainboard?

It has got a 3Pin Molex connector. If not I'll just use an external power supply.

[ultiarjan 1,223]

I mounted my 2 feeders (dual head) at the back of the machine and made a bracket with an old 60mm coollermaster pc fan, I run the 12V fan at 5Volt... it's super silent and still does a good job.

https://www.youmagine.com/designs/ultimaker2-rail-system-u2rs

@gr5 we had almost 40c last week and I'm still alive

[gr5 2,334]

@gr5 we had almost 40c last week and I'm still alive

 

That's pretty hot!

[kris 29]

Indeed, this solved the problem.

Cheers

[ultiarjan 1,223]

Nice,

here's a pic of my setup;

[neone 40]

same issue here (my first after a few prints).

I thought it was a nozzle prob so I tried changing filament, but it didn't move. Then I noticed the filament was jammed in the feeder.

ps it's 22C here right now so that can't be the issue I guess.