Trouble prining solid infil

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Capella_Ben
Posts: 88
Joined: Thu Aug 08, 2013 10:01 am
Location: Queensland, Australia

Trouble prining solid infil

Post by Capella_Ben »

After having problems with my V3 head (it actually lasted pretty well) I bought a V4.

The V4 looks better, especially as the tip is replaceable and it uses grub screws for the heater and thermistor.

However I am having problems printing solid infill. Perimeters prying really well and stick to the heated kapton really well. When it gets to the solid infill, the head seems to touch the previous line and drags it up and it all comes off.

The PLA seems to be extruding well.

Any ideas? Maybe change the extrusion width?

Ben
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Last edited by Capella_Ben on Sun Jan 19, 2014 9:26 am, edited 1 time in total.
Ben
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Felix 3.0 (upgraded from 2.0)

Capella_Ben
Posts: 88
Joined: Thu Aug 08, 2013 10:01 am
Location: Queensland, Australia

Post by Capella_Ben »

Image

This photo is not too bad. Most of the time it looks worse than that. But you can see where a section has come off the bed.
Ben
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Felix 3.0 (upgraded from 2.0)

Capella_Ben
Posts: 88
Joined: Thu Aug 08, 2013 10:01 am
Location: Queensland, Australia

Post by Capella_Ben »

I just noticed that after a failure, the kapton feels a little slippery where the PLA was. Now I always give the bed a really good clean with acetone, so it was perfectly clean to begin with. But when I take the failed print off the bed, it seems a little slippery (maybe even greasy underneath).

I'm going to try an ABS print to see what that does.
Ben
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Felix 3.0 (upgraded from 2.0)

andrewsi
Posts: 130
Joined: Mon Dec 23, 2013 1:26 am

Post by andrewsi »

Thoughts: Have you readjusted the z-limit for the new head? Any chance it's too high off the bed?
Also, that section on the left looks kind of messy, are you sure the flow rate is right/have you checked the actual average filament diameter and let the slicer know?
__________________________________________
Andy Silverman, Technogeek in Seattle
Felix Tec4 Single-head

Capella_Ben
Posts: 88
Joined: Thu Aug 08, 2013 10:01 am
Location: Queensland, Australia

Post by Capella_Ben »

andrewsi wrote:Thoughts: Have you readjusted the z-limit for the new head? Any chance it's too high off the bed?
Also, that section on the left looks kind of messy, are you sure the flow rate is right/have you checked the actual average filament diameter and let the slicer know?
Thanks for your suggestions.

I have adjusted the the Z limit and the bed. The bed is really level and the head is a paper widths height off the bed at home.

I haven't changed the flow rate. The filament diameter is pretty good. I have tried a few different spools to be sure.
Ben
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Felix 3.0 (upgraded from 2.0)

Capella_Ben
Posts: 88
Joined: Thu Aug 08, 2013 10:01 am
Location: Queensland, Australia

Post by Capella_Ben »

ABS is a problem as well. After a while the hot end will jam and the extruder wheel will strip the ABS and it will stop flowing. If I give it a bit of a push I can force it through and it continues on as normal.

I have tried increasing the temperature from 245 degrees to 260 and it still seems to do it every now and then.

As I have changed the thermistor (and indeed the whole hot end) could it be that the main board is having trouble reading the temperature?

I was thinking on modifying the firmware to use the pins for the second extruder and trying that. To do that I think I will need to modify pins.h in the Marlin firmware.

Any thoughts?
Ben
..
Felix 3.0 (upgraded from 2.0)

Capella_Ben
Posts: 88
Joined: Thu Aug 08, 2013 10:01 am
Location: Queensland, Australia

Post by Capella_Ben »

Here is a video of the problem. https://www.youtube.com/watch?v=_FeWu0my7lo

Any help would be appreciated. This is driving me insane. :?
Ben
..
Felix 3.0 (upgraded from 2.0)

Capella_Ben
Posts: 88
Joined: Thu Aug 08, 2013 10:01 am
Location: Queensland, Australia

Post by Capella_Ben »

If I remove the hot end from its mount I can manually push some PLA @ 195 degrees through. It take a little pressure, but it's what you would expect. I can do the same for ABS at 245 degrees.

While the hot end was out, I tested the extruder's grip on the filament. If I run it through at 100 mm/min and try to stop it by holding it, it is pretty hard to stop. I adjusted the tension and it was pretty strong.

So if the hot end is OK and the extruder is OK, maybe it's the alignment of the two?
Ben
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Felix 3.0 (upgraded from 2.0)

andrewsi
Posts: 130
Joined: Mon Dec 23, 2013 1:26 am

Post by andrewsi »

Just wondering if you had tried lower temperatures for your ABS too, e.g. 230ish? From looking at your video, I'm also wondering if slowing down your infill speed might have any effect. I mentioned it earlier, but how consistent is the diameter on the filament? Slic3r, in particular, claims to be somewhat sensitive to entering as exact an actual filament diameter as possible, not just the nominal 1.75mm.

I found an interesting web article which showed some measurements that for direct-drive extruders like Felix's, tightening the bearing down more actually reduces gripping power from the max possible because some of the motor's energy is expended on pushing against the bearing. The optimum tightening level is actually much closer to the point of disengagement from the bearing, which seems to agree with the (minimal) guidance in the Felix usage manual. Not that this is necessarily your problem, but it does speak against the value of the natural tendency to crank the extruder down harder and harder on the filament trying to get the max possible grip to solve jam issues.

Sorry I'm not being of more help, but I'm a relative noob myself.
__________________________________________
Andy Silverman, Technogeek in Seattle
Felix Tec4 Single-head

Capella_Ben
Posts: 88
Joined: Thu Aug 08, 2013 10:01 am
Location: Queensland, Australia

Post by Capella_Ben »

I have done a lot more testing and it seems that this problem is to do with too much moisture in the filament. It's been pretty humid here and it seems to be having an effect.

After a bit of careful drying in the oven I can see better results. I have a 1Kg bag of desiccant on order, after looking at this video I should be able to get it under control: http://www.youtube.com/watch?v=V3LpN7WA0pw
Ben
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Felix 3.0 (upgraded from 2.0)

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