Weird issue - see attached pic  

guess

I can’t see your first layer but I would guess you bed is dirty or you Z offset is not ideal.  If that is the case, your fist layer is buldging off the bed and the nozzle is hitting it.  

Getting there

The weird thing is that I’d given the bed a proper clean with washing up liquid just five minutes before this.

Well, it behaved itself for the rest of the print, and I’ve started another one now.  I'll run some calibrations later and see if that shows up any issues.

user error suspected

Well, the Z-layer height - and first layer - were as I suspected pretty close to perfect.  But the next piece I printed was just as bad - possibly worse.  That's because I had loaded PETG by mistake (which I rarely use), and it wasn't hot enough for the layers to adhere properly - causing that lifting and dragging.

Gone back to the problematic grey PLA, knowing that the finish won't be perfect but it's not mission-critical. And I'll order more filament later. 

PETG

That explains the problem.  Keep us updated.  

Posted by: @richard-d

Well, the Z-layer height - and first layer - were as I suspected pretty close to perfect.  But the next piece I printed was just as bad - possibly worse.  That's because I had loaded PETG by mistake (which I rarely use), and it wasn't hot enough for the layers to adhere properly - causing that lifting and dragging.

Gone back to the problematic grey PLA, knowing that the finish won't be perfect but it's not mission-critical. And I'll order more filament later. 

Not really any better ….

Still pretty shocking behaviour from the current filament.  The first two or three layers in particular - but it makes a weird "fingernail running along a comb" noise from the hot end too.

Unfortunately I’m partway through a largish, multi day project that I want to finish with this particular colour.  Then I’ll strip the extruder (as it probably needs a clean out), take a look at some hot end maintenance, and consign this filament to the "do not use" pile.  Shame, as I like the colour and it was supposed to be the brand's "premium" line.

I am surprised

I am surprised it is the filament.  There are only a few that I cannot get dialed in.  

Posted by: @richard-d

Still pretty shocking behaviour from the current filament.  The first two or three layers in particular - but it makes a weird "fingernail running along a comb" noise from the hot end too.

Unfortunately I’m partway through a largish, multi day project that I want to finish with this particular colour.  Then I’ll strip the extruder (as it probably needs a clean out), take a look at some hot end maintenance, and consign this filament to the "do not use" pile.  Shame, as I like the colour and it was supposed to be the brand's "premium" line.

Dialled in?

I’m not normally fussed about trying to get things dialled in; PLA seems pretty forgiving, and normally I just print with everything set to the default.  But this particular spool of filament was a bit of a sod to print with last time I used it, too.

The retailer had a nice recycled PLA that was almost the same colour and which behaved perfectly.  So they discontinued it when I was still about 200grams short of finishing a multipart piece 🙁

A thought

Maybe what you have is not PLA.  It is not unheard of and I have seen it a few times.  

Posted by: @richard-d

I’m not normally fussed about trying to get things dialled in; PLA seems pretty forgiving, and normally I just print with everything set to the default.  But this particular spool of filament was a bit of a sod to print with last time I used it, too.

The retailer had a nice recycled PLA that was almost the same colour and which behaved perfectly.  So they discontinued it when I was still about 200grams short of finishing a multipart piece 🙁

You're probably right

A new delivery of filament -including the previously "discontinued" stuff, a swap to a different spool, and it's *perfect* again.