3d Solex Printcores material throughput to low

[Muselmann 0]

Hello,

I operate an Ultimaker 3 at my Workplace. We bought a 3D Solex Printcore about a year ago as a replacement and the prints were good.

After we updated to Cura 5.0 we encountered problems of underextrusion and worst of all the Feedwheel grinding itself into the PLA Material.

I tried everithing i could think of.

I cleaned the feeder - didn't help

I replaced the nozzle - didn't help

I replaced the Printcore - didn't help

I updated to 5.1 - didn't help

I downgraded to 4.13.1 - didn't help

 

I am pretty shure , that the Printcore or the nozzle is the problem.

I made a testprint with an Ultimaker Printcore and the print went fine, with no problems.

I also noticed that when loading the Ultimaker core, that the ammount of plastic pushed through the nozzle is higher, compared to the Solex core and when i pust by hand the ultimaker nozzle is easyer to push through then the Solex.

 

My suspicion is that the 3 internal holes in the nozzle are obstructing the flow to a point, where printing is possible for small or short prints. But to be honest i am shooting into the dark here.

 

Does anyone have an explanation or solution to the problem, e.g. lowering the printspeed to a point where the low throughput is compensated for.

 

Kind Regards

Musel

 

Pressure setting of the Feeder

Grinding on the Material during printing with no support and as little retraction as possible.

Grinding on the Material, when Material is loadet into the Printhead and getting pushed through the nozzle.

[gr5 2,235]

The 3 holes definitely improve flow - there are some great videos from "CNC Kitchen" on youtube basically proving that it's much better.

 

It's good to have some tricks to isolate the problem.

 

Trick 1: Test feeder.  It's probably not the feeder but it might be so let's eliminate the feeder right off.  The feeders do age - there are some plastic parts inside that can completely wear out.  So lift that lever and pull back the filament so that it is half way down the bowden.  Now go into the menu system and get to the MOVE feature where you can move the material - move the material and then fight that by pulling hard down below the feeder with the other hand.  The feeders typically fail at about 7kg of force where the filament slips backwards but anything over 4kg should be plenty.  Maybe lift a 5kg weight (if you can find something - or maybe a few liters of water?) to compare the force or I've kind of squeezed a 5kg weight against the filament below the feeder such that the filament is basically holding most of the weight.  Make sure the feeder can advance the filament forwards while being held back by 5kg.

 

Trick 2: now test flow.  See how fast you can extrude through the nozzle.  Typically you can get the filament to go from the nozzle down to the bed (when all the way down) in about 10 seconds with a 0.4mm nozzle.  If it takes > 20 seconds then there is a problem somewhere.  Again - in the move menu, it will heat the core.  wait for the nozzle to heat up and then turn the knob to get the filament to move.  Try to find the max speed.  Put a kink in the filament just outside the nozzle so you can see how long it takes to get down to the glass.  Slowly adding movement with one hand constantly to try to achieve max speed (if you move too fast with the feeder it can actually slow down a bit).

 

1) Please post your project that definitely failed.  If you don't mind sharing the STL.  Go to "file" "save project" and post the resulting file here.  Just so I can see if you are printing too fast or something I wouldn't normally expect.

 

2) Make sure the fan is working in the print head - the center fan.  It should start spinning as soon as either core is above around 60C.

 

3) Is the problem only on the right core?  You only show a photo of the right feeder.

 

4) Is this PLA?

[Muselmann 0]

Hello gr5,

thanks for the fast reply.

 

The project was a ER Collet holder from thingiverse. In my attempt to troubleshoot i reverted to the standart print profiles to be shure its not a setting problem.

When i was loading the Material i noticed that the material was moving in a  stop and go motion and made a scraping noise untill it entered the guide tube of the Printcore. (see Video)

I had just cleaned the Bowdentube and Feeder, so it schuldn't be dirt.

 

The fan starts blowing at 60°C as intendet.

 

I just made the same flow tests on the left core/Side and even with the Solex Core.

At the moment the Core setup is original Ultimaker Core on the left Solex core on the right.

the extrusion seems to be fine in both cores.

 

We use PLA  from ICE

UM3_ER16_15-collet_box_v8.3mf video_20220825_162414.zip

[gr5 2,235]

Everything looks fine.  I can't see how it can possibly be the firmware

 

So there has certainly been some occasional issues with 3dsolex cores (there are sometimes issues with UM cores as well- I'm not saying they are better or worse the UM cores) where there are problems just above the heatbreak - there is teflon under the aluminum heatsink and that teflon should be the same diameter as the heatsink just below it.

 

You can cut the teflon tube a little short or a little long.  If it's too long and you compress it then it squeezes the filament a bit which is actually typically ideal.  You don't want semi-soft filament expaning *above* the heat break.  If it does and then cools a bit then you get underextrusion just as you describe.  Or you can have trouble removing the filament after the print is over if the heat sink diameter is larger than the diameter of the "trumpet" just above.  Or even the top 5cm of the heatsink can be smaller.

 

So basically you want the inner diameter of the core to be really the same all the way until you get below the heat break and then it doesn't matter.  Or preferably slightly smaller in diameter just above the heatbreak than the diameter above and below the teflon.

 

Have you had any trouble with removing filament after a print?  If so then i'd say that's the problem.

 

I guess I'd contact 3dsolex and maybe ask if they can send you a different core or something.  sales@3dsolex.com usually works.

 

[Muselmann 0]

Thank you gr5 for your help.

I will try to figure it out. now i have a point to start from

 

Kind regards

Musel

Edited August 30, 2022 by Muselmann