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Suddenly Flow rate not enough

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My ultimaker was running fine. But the last two prints i had trouble because the filament that comes out of the hot end is now too thin ( this happens after the first layer). I have the fear that this is the first sign of a so called plug. If i increase the temperature (from about 200 to 215) and also the flow rate (from around 210 to 213) then i get my normal nice prints back. The problem occurred with two different filaments (red and green UM PLA) .

When i try to extrude by hand this works fine and i do not need any force to do that.

So is this a first sign of a plug at the hotend or just some variation in filament thickness?

I do not have calipers to meassure that. Is there any way to test for a plug? Or do I have to open the hotend?

Thanks in advance,


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Your only way to reliably check for a plug is to take apart the hot end. I've had ones where manual extrusion still worked, but whilst printing the flow is just too small. You only have to undo e four large screws and lower the peek away from the tube, not take the whole hot end apart. Read the wiki page before you begin. Once you have it back together put a small mark on your Bowden just where it passes through the top piece of wood of the hot end, then you can later monitor to see if it's slipped and thus almost certainly has a plug.

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