V4 Heat Creep - Melted Plastic Above Hot End

[kartcrg]

I just upgraded to the V4 and am getting melted plastic between the filament drive and hot end during prints. This is with PLA at 200º. Do I have something set up wrong?

[Vandal968]

The feeder nozzle (cold end) is not supposed to touch the hot nozzle. On mine there is perhaps a 3/16" gap between the two. It looks like yours is touching which is no bueno unless it's just a weird camera angle.

cheers,
c

[kartcrg]

The feeder nozzle (cold end) is not supposed to touch the hot nozzle. On mine there is perhaps a 3/16" gap between the two. It looks like yours is touching which is no bueno unless it's just a weird camera angle.

cheers,
c

Thanks mate, thats what I figured. Problem solved.

[sthone]

Yeah once you have that gap between the two there is no such thing as heat cheap on the V4.

[kartcrg]

I wonder why the extruder fan is even necessary? Would happily ditch it and it's noise if it doesn't make a difference.

[sthone]

I wonder why the extruder fan is even necessary? Would happily ditch it and it's noise if it doesn't make a difference.

In my opinion it's not needed. I've been running one of my printers for the last 3 months without the extruder fan and haven't had any issues. The only thing is you just can't just unplug it as the extruder and case fan are both 12 volts and run in series. (they may have changed this on newer printers) I bought a 24 volt fan for the electronics case but the fan I bought almost seems louder than the two 12 volt ones so if sound is the only reason you are changing it it's not worth it unless you find a quieter fan.

-Steve

[kartcrg]

In my opinion it's not needed. I've been running one of my printers for the last 3 months without the extruder fan and haven't had any issues. The only thing is you just can't just unplug it as the extruder and case fan are both 12 volts and run in series. (they may have changed this on newer printers) I bought a 24 volt fan for the electronics case but the fan I bought almost seems louder than the two 12 volt ones so if sound is the only reason you are changing it it's not worth it unless you find a quieter fan.

-Steve

Good to know. Do you print high temp plastics with that printer? I also struggle to find any reason it might be needed, it's not like the extruder stepper / gearbox get that hot and the fan is well above the top of the hotend. I'm thinking ditching the electronics fan as well might be pushing it thought though? So maybe looking for a quiet 24 v fan is the way to go.. Unless there is 12 v pins somewhere on the rambo to run a fan off of?

[Tim]

Unless there is 12 v pins somewhere on the rambo to run a fan off of?

No, there's not, but it's easy to get a "buck converter" which is a tiny little circuit board with a voltage regulator and a few other components. Get a variable-voltage converter or a fixed 12V converter. Connect the "in" side to a 24V output from the RAMBo, and the "out" side can be connected to one or more 12V fans in parallel. The buck converters are so small that you can just toss a couple of them inside the electronics box---just wrap some electrical tape around them to make sure they don't touch anything on the RAMBo itself.

Once you have a 12V supply available, you also have a place to connect your LED strip.

[Matt_Sharkey]

I would say the extruder fan is somewhat necessary, it's the final nail in the coffin, so to speak, to prevent heat creep.

This is my speculation without owning a V4...

[sthone]

Good to know. Do you print high temp plastics with that printer?

I print mostly PLA on this printer (@ 215°) but checking it with one of those laser temp gauges against my other printer running abs and petg there are hardly any difference in temps between mounts, extruder motors, or filament guides.

I would say the extruder fan is somewhat necessary.

It's not... heat creep is pretty much impossible with one... If setup right there is separation between the filament drive and the hot end so there's no way for heat to creep up there. Granted my longest prints are 12 hours but like I said I haven't had any problems in the 3 months I've been running without a fan so I can say in my opinion the extruder fan is not necessary with the V4.

-Steve