UM2 popping noise when printing rafts

[Kirbs 0]

When I print rafts with my UM2 ive noticed a popping noise created randomly as it goes around.

I've honestly got no idea what's causing this but it doesn't sound great.

 

Many thanks in advance

[gr5 1,026]

That sounds very familiar.  I think you have the black feeder on your ultimaker and it's skipping backwards.  Watch the feeder while this noise happens - you should see it jerk back.  It's not going to damage your printer.

 

The problem is you might get some underextrusion for a few seconds afterwards.  If so you can fix this whole problem by moving the bed a little farther from the glass so you aren't squishing so much.  I'm not a big fan of that solution because then the part won't stick as well.  

 

You could also raise the temp a bit on the bottom layer.  Or get a more powerful feeder (like the meduza feeder ($19 USD in my store in USA/canada - thegr5store.com), the bondtech feeder (much more than $100), or the plus upgrade from ultimaker (around $400 I think USD).

 

Or you could make the bottom layer 0.1mm thick instead of the default which is around .3mm thick.  That's a good option as well.

 

[Kirbs 0]

Thank you gr5, I had the first layer hight set above what it should have been, turned it down and is working flawlessly.

Thank you