UM2: Under-extrusion on first couple of layers

[RFrancis 0]

I have an old Ultimaker 2 which hasn't seen any use for a couple of years. I've now brought it back into use because I'm selling it.  I'm having problems with under-extrusion for the first couple of layers. After that it seems to print well.

 

I attach an example of three separate test prints, where we've played with various settings. (We is me and the buyer)

 

The filament is Formfutura PLA, bought in 2015, with the printer!  I dried it on the build plate for about 8 hours.

 

The printer has an Olson block, and for these tests it had a previously unused 0.6mm nozzle.

 

We cleaned the feeder and slightly increased the tension (it was at the lowest setting) and replaced the PTFE coupler. Those actions were in-between these tests and clearly that didn't make much difference.

 

 The buyer is going to buy some new filament and see if that is the solution. Other than that I'm at my sits end to figure out what's wrong.

 

Any ideas?

 

Thanks,

Richard