1 Topic by sonrix

  • sonrix
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Topic: Can t get a constant filament diameter

Hello,

I am extruding ABS at 182degree Celsius on a vertical mount.
I have no filawinder, but the system hangs free in the room and the filament may fall freely without touching anything but the floor.

The filament diameter constantly shifts up and down from 1,69 to 1.82. I had more constant extrusions a few days ago.

I suspect one of two reasons:

I think that it is the gears worn out. (After maybe extruding only 15-20 Kilos of filament in total)
Or the system has not enough power to heat up and power the motor on a constant rate.

Has anyone tried using a better powersupply?
And what can I expect from filastruder.

I plan to inspect the gears tomorrow and change out the grease.
Also I want to take off the nozzle and see if there is any problems there.

But so far I never had good quality extrusions. Any cheap filament is way better than what my machiine has produced.

2 Reply by sonrix

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Re: Can t get a constant filament diameter

Ok, the gears and the coupler (auger or what you call it) are fine.
There was a bid too few grease in it which accumulated at one spot but that was no problem to fix.

I will see how the nozzle looks like next.

3 Reply by sonrix

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Re: Can t get a constant filament diameter

Ok, Nozzle is ok too...

Can it be the motor? Or the power supply? Or both?

4 Reply by slistack

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Re: Can t get a constant filament diameter

whats the distance from the nozzle to the ground?

5 Reply by sonrix

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Re: Can t get a constant filament diameter

65 cm.

Motor looks ok too. But I had the cooler for the motor more blowing onto the gearbox instead of the motor after shifting from horizontal to vertical.

That may have caused shifts in diameter once the motor got hot.

Also the thermocouple may deserve a better fixation. It was clamped to the nozzle. But the clamp is pretty large and the thing may not have been as fix as desired. I will use the capton tape first and then a clamp instead.

With heat and space for micro movements, that may have caused problems as well.

6 Reply by sonrix

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Re: Can t get a constant filament diameter

Ok, now I have fixed the thermocouple with high temperature silicone to the mounting hole and used capton tape. But extruding still results in variing diameters. I will do a longer test.

But I think that there may either be too few power on the motor for constant extrusion. Or the pellets may have taken too much humidity. I have dried them before use though...

Or what was your idea about the mounting hight? Should I try more distance or less distance?

7 Reply by elmoret

  • elmoret
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Re: Can t get a constant filament diameter

65cm is too low, you're causing the filament to create too sharp a bend, putting veriable tensile force on the molten polymer.

Filastruder - the robust, inexpensive filament extruder
E3Dv6 All Metal Hotend - the premier 3D printing hotend

8 Reply by sonrix

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Re: Can t get a constant filament diameter

ok, I found the 1,5m recommendation and have installed it so that the nozzle will be 1,55m from ground. Test will run tomorrow.
All thanks for answering.

Maybe the troubleshooting is helpfull for someone else.

9 Reply by sonrix

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Re: Can t get a constant filament diameter

Ok, ran it from 1,55 meters nozzle distance to ground and it needed about 14degree Celsius less heat.

The messurements still were wide spread. In between 1,65 and 1,8.

But I finally examined my digital messuring tool. And by wiggling around and adjusting the spring loaded leg that presses the filament I was able to get every mesurement close to 1,75 and down to 1,65. (Made in China)

So the conclusion of all this is: It may not be the filastruder. And the filament may be totally ok. Even the ones before. But I need a more precise messuring tool.

Anyway the higher nozzle position is good as far as I can tell. The filament lays down in a much wider radius with less curving and probably is totally stiff before hitting ground.

Also the lower temperature needed produces less fume and needs less electricity.