First layer random under extrusion

[niophys 0]

Hi! Has anyone experienced under extrusion on first layer only?

The photo attached show the beginning of the print with some parts under extruded. If I let it print, the following layers will be fine.

I've re leveled the bed multiple times, and it looks good to me. Cleaned the nozzle, cleaned the feeder.

Not sure what to try next to fix this.

Any advice would be much appreciated!

Thanks, Mathieu

[SandervG 1,521]

Hi Mathieu,

How is your process and 3D printing experience going so far?

Just came across your post, and it looks like your bed is levelled to low. Especially in the back. This results in layers not sticking to the bed properly, and can be easily dragged of by a moving nozzle or string of filament. Did you know there are 3 thumbscrews on the bed?

2 in front, 1 in the back?

Is there a ticking sound at your feeder? Could you describe (or record) the frequency?

Good luck!

[dimitrisFeelform 1]

I have the same problem, is there anyone who has an explanation?

[gr5 2,265]

The bottom layer is thicker than other layers so it takes more pressure to get the filament out so you are more likely to get underextrusion. Also the software assumes the head is exactly .3mm off the bed when it is printing the .3mm layer but if your leveling is off by just .1mm then it might be only .2mm of space so again, that can cause a lot of pressure in the head trying to squish .3mm of filament into .2mm of space - the pressure builds up and up and eventually something has to give.

The solution is usually to print hotter and/or slower on the bottom layer. Try cutting speed in half again (you can experiment in the TUNE menu while it's printing) and try raising temp to 240C just for the bottom layer. Also consider moving the glass *away* from the nozzle by 1/3 turn on all 3 leveling screws by equal amounts.