SoliForum - 3D Printing Community — Extruder spits too much filament

Re: Extruder spits too much filament

2015-10-09T09:33:38Z

Dear all,

Thanks a lot for all your responses ! After levering the bed, I had some other troubles but this time, described in the wiki. I fact, I didn't use my printer for a long time and it does need a complete re-calibration.

Now the result is much better. Still not perfect but really more better! I will try to find someone in Belgium who can help me to calibrate it to make it perfect.
For the moment I am happy to be able to print again :-)

Many thanks again !

Re: Extruder spits too much filament

2015-10-01T14:46:27Z

Two other things to note.

First, I had a 3D model that was just slightly tilted by a very small amount and would not sit flat on the build space. It is hard to find and hard to fix. I found it by zooming in and looking at the first layer with the gcode viewer.

The other issue may be that your bed is not level. I have three 3D printers, and none have a completely level bed. While a glass bed usually fixes this, a thin piece of glass can warp on a warped bed.

Re: Extruder spits too much filament

2015-10-01T05:59:11Z

The Teflon blocks both for the X and right y carriages are supposed to be snug. To tighten them loosen the screws both top and bottom and pinch them together with your fingers. While holding them snug tighten the screws.
I repeat... The Teflon blocks are to be snug. They are not spring loaded and were never designed to allow the extruder to move up and down. If your printer is snagging the previous layer and skipping steps it's time for some serious calibration.

Re: Extruder spits too much filament

2015-09-30T18:59:47Z

Ah, I didn't notice that acrylic extruder. Yes, the teflon blocks are in both X and Y on your machine. I disagree, however: you want it tight. Any slop in the hotend is bad. It's better to skip on raised portions (which has never happend to me) than have slop.

Re: Extruder spits too much filament

2015-09-30T17:43:00Z

When you adjust the bed use small movements. 1/4 turn down for the parts that do not have enough filament, 1/4 up for the parts that have too much (only if adjusting down does not work).

Re: Extruder spits too much filament

2015-09-30T17:32:33Z

Try lowering the bed first and see if that helps. Also do a steps per mm and cube calibration if you haven't already done so.

If after moving the bed down a bit and checking your extruder calibrations, you might want to check for slop in your carriages, which rides on teflon blocks on the right side. Grab your carriages (left and right) and try to move them up and down. How much slop is there? If it can move quite a bit, you can tighten the grip on those teflon blocks by tightening the screws; they just float on the rod.

Re: Extruder spits too much filament

2015-09-30T09:10:07Z

Thanks for your reply. I will try to move down the bed and see what happens.

To be honnest, I don't really understand the things with the Teflon... Do you advice me to try something else than to move down the bed? If it is, can you be a little more explicit about what I have to do?

Re: Extruder spits too much filament

2015-09-28T15:57:50Z

I tend to agree with wardjr. Certainly looks like the bed is either not leveled correctly and/or is too close to the nozzle. If there is not enough room for the filament to extruder, pressure builds up. Particularly at turns where large amounts of filament extrude, you might wind up with the pressure over-extruding the way you are seeing. Then, once the pressure is relieved, you are still printing too close to the plate. That is why you are seeing almost nothing in the areas between. Wardjr is right that normally there is some give with the Teflon blocks. With a high enough infill, this might correct itself a few layers up. However, the unevenness will continue through the print.

Re: Extruder spits too much filament

2015-09-28T14:34:23Z

It is difficult to see with that filament but I would suspect your nozzle is simply a little too close to the bed on that first layer.
Then, given the fact that the original carriage runs on two Teflon blocks on the rear rod. As the pressure builds in the nozzle it tries to lift the nozzle off the bed. If the Teflon blocks are loose enough it will allow the nozzle to lift slightly and cause what you are seeing in the photo.

Re: Extruder spits too much filament

2015-09-28T06:43:31Z

Nobody? :-(

Extruder spits too much filament

2015-09-24T13:57:51Z

Dear all,

When the model requires a long rectangle, the extruder will always spits too much filament during a part of the model (at random). As an image is better than a long message, I post you two photos of the same model printed at different times.

It always happens during the first layer and there are so much plastic that the printer shakes when the extruder comes back (and I am sure that it is not good for the machine).