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Initial print issues

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Hello

I've had my Ultimaker a few months but am only really getting time to work on it now. I seem to be having some flow issues, or at least that's what I think the issue is.

So far most of my results look like this (using Netfabb btw at a temperature of 210C) - http://imgur.com/a/lYINA.

This is just the first few layers of a print, but as you can see, the structure is not very solid. This was a standard quality filled object, on higher quality settings the outside (ignoring the top) of the prints are usually great, almost perfect, but the inside is still so sparsely filled that the objects break apart as they are removed from the print area.

I have checked that when the plastic is not being forced into the hot end, the printer extrudes nearly the exact amount of plastic that is asked from it. I have not accurately checked this when it is being pushed into the hot end though.

So my main question is, does anyone recognise what I'm doing wrong?

Thanks for your help.

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Hallo,

in the Slicer you can set the infil in %. That the inside is not solid, is normal. It saves material. But you can set the infill to 100% if you like.

I see a different Problem. Your belts are not tighten. Your infill will not touch the one side and go over the wall of the other side. Tighten all belts will fix this.

The first and last 1-2 Layer must be solid.

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That looks a lot like some of my failed prints. My prints fail when the extruder chews away or breaks the filament. I've bumped up the temp to allow the PLA to flow better, about 5C at a time, and closely monitored the feed while I'm printing, adjusting the tensioning screw as necesssary. This has given me about a 80% sucess rate, with the occasional fail from unknown causes, probably filament inconsistency.

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My prints look like this if the filament is not taken in by the extruder.

The extruder bolt grinds away part of the filament and there is not enough force to push the filament into the bowden tube.

In my case it happens when the filament diameter gets above 3 mm. Also in this case I can not push the plastic in by hand anymore. Meaning open the extruder and try to push the plastic manually.

What I do then is remove the filament and measure the thickness, cut away the too thick part and start again.

I discovered this when investigating how much filament is transported on several extruder settings. I began with an empty bowden tube and started feeding. After a while the extrusion stopped grinding away the plastic. The end (or beginning) of the filament was in the middle of the bowden tube just were it is most curved. When I took out the plastic and measured the diameter It was 3.1 mm.

Also using netfab but at 230 C. This gives a nice shiny surface.

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Another thing poped up in my mind.

The tensioning screw for adjusting the force of the filament agains the hobbed bolt ( as suggested by prather).

One time when I tried to adjust the screw in order to start the extruding again it was very tight when I turned it.

But still no Extrusion. I took the thing appart and discovered that the screw was not even pushing agains the plastic.

The plastic screw is mounted with a Nylock nut. When turning, I just felt the force from the nylon in the nut and not from the plastic against the hobbed bolt. What I do now is opening the extruder using the plastic clip so I can see the screw pushing the plastic out and then close the extruder again.

I also measured how much the tensioning screw needs to be turned inwards before the plastic is hit.

Mine is at 12.2 mm

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