Print failure: second extruder hits the print.

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Fel.dufrenoy
Posts: 1
Joined: Sun Jul 12, 2015 9:26 am

Print failure: second extruder hits the print.

Post by Fel.dufrenoy »

Hello the Community!
I'm pleased to join the felix team.
I have a flexi V3.0 dual extruder coming from the DIY kit since the Jully 2015.

When I try to print a part, my second nozzle hit the print.
I'm using default parameters.
My bed is correctly leveled
My two nozzles are correctly leveled (with a paper between nozzle and bed).

In general, when printing reaches a height of 20mm, the second nozzle start to rip the last printed layer. Little by little, he just impact the piece being printed. This phenomenon produces an increase in Z that , at last, produce an impact which unstick the print from the bed.

Could you help me?

with regards

Sentinyl
Posts: 3
Joined: Wed Jan 27, 2016 3:33 am

Post by Sentinyl »

Fel.dufrenoy wrote:Hello the Community!
I'm pleased to join the felix team.
I have a flexi V3.0 dual extruder coming from the DIY kit since the Jully 2015.

When I try to print a part, my second nozzle hit the print.
I'm using default parameters.
My bed is correctly leveled
My two nozzles are correctly leveled (with a paper between nozzle and bed).

In general, when printing reaches a height of 20mm, the second nozzle start to rip the last printed layer. Little by little, he just impact the piece being printed. This phenomenon produces an increase in Z that , at last, produce an impact which unstick the print from the bed.

Could you help me?

with regards

Good morning (from Florida)!
So I work with 3 Felix printers at my work, and after messing with a V2.0, and two V3.0's with the 3.1 upgrade(s)--I think it is safe to say that this is why the Felix Pro 1 tackles this dilemma. From what we've seen, the dual extrusion for the 3.0 and 3.1 are not the best, in a sense--we found that when the filament for the first head stops, and the filament for the 2nd head begins, the 1st head still "drips" or leaks onto the print, which can be catastrophic if you are not there all the time. We run our printers day and night for prints, and we have to print 16 hour large volume prints often for projects. We can't afford to fail prints that often. We are even considering to get the PRO 1 because the heads actually move out of the way when the other is in use! That makes the dual extrusion far more worth it.

Because of this experience with the dual extrusion, I purchased a single extruder head setup.

BUT, to assist you with your problem, I would use calipers to measure the assembled extruders overall lengths. Make sure they are the same height. Otherwise it will have potential to grab on some residual strands and globs from the first head. My recommendation is to use the 2 heads only when you can keep an eye on the print (whenever the extruders exchange tasks).

kerog
Posts: 117
Joined: Mon Jun 09, 2014 1:54 am

Post by kerog »

To prevent dribbling, you need to let the extruder not in use go to a "rest" temperature, like 30-40 deg below print temp, as well as retracting a fair amount. In my experience, there is no slicer that does this really well, but KISSLICER does the best.

Also make sure your slicer is set to lift on moves, and printing a full-height skirt helps as well. The 3.1upgrade has a mechanism that helps you really dial in the relative positioning of the two heads and keep them firmly in place. Without it, the tips can move up and down a bit as filament retracts and extrudes. If you know what you are doing you can account for this when you level and it can actually be a help, but mostly it messes you up.

Hope this helps.

-Keith

venkel
Posts: 17
Joined: Thu Dec 17, 2015 2:29 pm

Post by venkel »

Simplify3D can cool the other extruder on tool change. Add this script to "Edit Process Settings / Scripts / Tool Change Script":

; XXX = set tool temperature
{IF NEWTOOL=0}M104 S140 T1 ; Set T1 inactive extruder to 140 C
{IF NEWTOOL=0}M109 S190 T0 ; Set T0 new active extruder to XXX and wait for temperature.
{IF NEWTOOL=1}M104 S140 T0 ; Cool T0 to 140 C
{IF NEWTOOL=1}M109 S190 T1 ; Set T1 Heat T1 to XXX

Change "140" to the desired parking temperature and "190" for the printing temperature. Sadly the variables [extruder0_temperature] and [extruder1_temperature] seem not to work.

Add a prime pillar or ooze shield to allow the nozzles to start up properly before printing.

Only problem with S3D is strange behaviour of the temperatures during printing of the skirt, but after that all works fine.

***********************************************

The FelixBuilder software does an even better job changing temperatures on tool change. And print speeds are individually set for each material, very nice.

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