Ultimaker Go first layer print problem

[JimT 8]

I have an Ultimaker Go and it is not printing the first layer correctly. (See photo.) It appears that the filament stops extruding in places. The feeder motor makes a clicking sound when this happens. It only happens on the first layer. Other layers print correctly. It never happens when printing the first layer of the outer wall, only when printing the first layer within the outer wall. I tried raising the temperature to 230 and lowering the print speed to 75% on the first layer, and that helps a lot, but it doesn't completely stop the problem. (The photo was taken at 210 degrees and 100% print speed.) I've had the same problem with different colors of PLA from different vendors. Relevelling the bed didn't help. I've also tried the atomic method to clean the nozzle and that didn't help either. Can anyone tell me what's wrong and how to fix it?

Edited January 18, 2018 by JimT

[gr5 2,167]

How old is this printer?  You might need a new teflon part if you've been using this for a while (hundreds of hours).

 

Anyway the bottom layer thickness defaults to 0.3mm so assuming the future layers are .2mm or .1mm obviously you are printing significantly more plastic on the bottom layer.  That is part of the issue.  The other issue is how much you are squishing the filament into the bottom layer - leveling.  I know you said you re-levelled but there are many choices as to where you position things for the bottom layer.  I personally like to level such that the bed is extra close and I get extra squish.  But that also means I have the danger of happening what I see here.

 

Anyway I have a um2go with the original black feeder and I always do 0.3mm on the bottom layer and I squish the bottom layer badly so I think something is wrong with your printer most likely.

 

How old is it?  You can check hours printed in the menu system.

[fbrc8-erin 272]

Also, what's your first layer printing speed?

If you go into the Tune menu and slow down your gcode during the first layer, does the first layer print okay?

[JimT 8]

2 hours ago, gr5 said:

How old is this printer?  You might need a new teflon part if you've been using this for a while (hundreds of hours).

 

Anyway the bottom layer thickness defaults to 0.3mm so assuming the future layers are .2mm or .1mm obviously you are printing significantly more plastic on the bottom layer.  That is part of the issue.  The other issue is how much you are squishing the filament into the bottom layer - leveling.  I know you said you re-levelled but there are many choices as to where you position things for the bottom layer.  I personally like to level such that the bed is extra close and I get extra squish.  But that also means I have the danger of happening what I see here.

 

Anyway I have a um2go with the original black feeder and I always do 0.3mm on the bottom layer and I squish the bottom layer badly so I think something is wrong with your printer most likely.

 

How old is it?  You can check hours printed in the menu system.

I've got 544 hours of print time on my printer. The problem seems to have gotten worse recently. Is there a way to tell for sure that I need a new teflon part?

[JimT 8]

2 hours ago, fbrc8-erin said:

Also, what's your first layer printing speed?

If you go into the Tune menu and slow down your gcode during the first layer, does the first layer print okay?

I always use the default print speed. Lately, I've been using the Tune menu to reduce the speed to 75% and increase the temperature to 230 at the start of the print, and then return those values to normal after the first layer has printed. As I posted, that helped, but did completely solve the problem. 

[fbrc8-erin 272]

The UM2Go uses a PTFE coupler, which I usually recommend replacing around 500 hours, but you can go ahead and take apart the printhead and inspect your coupler. I wouldn't expect your coupler to be as discolored as this, since these had been printing ABS, but if you look at the ridges on the inside and the fact that the interior is widened out on the two dark ones and compare it to the new coupler on the left, it should give you an idea of how they look with wear and tear. 

 

[JimT 8]

3 minutes ago, fbrc8-erin said:

The UM2Go uses a PTFE coupler, which I usually recommend replacing around 500 hours, but you can go ahead and take apart the printhead and inspect your coupler. I wouldn't expect your coupler to be as discolored as this, since these had been printing ABS, but if you look at the ridges on the inside and the fact that the interior is widened out on the two dark ones and compare it to the new coupler on the left, it should give you an idea of how they look with wear and tear. 

 

Thanks. I'll check it out.

[JimT 8]

Are there any other parts that should be replaced after 500+ hours?

[gr5 2,167]

I don't think so, no.  Clean all the rods and add one drop of oil to each one.  I was going to say "clean the glass in the sink completely" but you probably don't have the heated bed kit.  Make sure you clean blue tape with rubbing alcohol before you print on blue tape.

 

I'd get the ptfe part from fbrc.com where Erin works.  I sell these also but I'm out of stock.

[fbrc8-erin 272]

We've got couplers in-stock over at fbrc8.com; you'll want to search for TFM coupler though rather than PTFE. A little more durable than PTFE; it's what's used in the UM2+.

[yellowshark 153]

Well it is strange that the walls are fine but not the infill. To me that suggests you are printing the infill at a faster speed. You do not say what speed you are printing at (.i.e. 100% of what?) nor if your infill speed is different to your wall speed. The clicking suggests a feed problem. One thing is for sure and that is if you have to raise the temp. to 230 , at a reasonable speed, then you have something . On the other hand if you are printing at 100mm/s that is probably your problem, although I am not convinced that would cause clicking if the walls are at the same speed.

[JimT 8]

23 minutes ago, yellowshark said:

Well it is strange that the walls are fine but not the infill. To me that suggests you are printing the infill at a faster speed. You do not say what speed you are printing at (.i.e. 100% of what?) nor if your infill speed is different to your wall speed. The clicking suggests a feed problem. One thing is for sure and that is if you have to raise the temp. to 230 , at a reasonable speed, then you have something . On the other hand if you are printing at 100mm/s that is probably your problem, although I am not convinced that would cause clicking if the walls are at the same speed.

As I wrote previously, I always use the default speeds.  For the UM2Go, that's 30 mm/s for both the bottom layer and the outer wall.

[yellowshark 153]

Thanks, sorry but I started life with another slicer so I have never investigated standard settings. You should be able to run that at < 210, even <200. You might be surpassed at how much difference running the first layer at 20mm/s can make too. You are getting good advice on the UM hardware so stick with it

[gr5 2,167]

After you replace the teflon part with a TFM, if you still have issues let us know here and I'll post my big list of possible underextrusion causes.