All of sudden, I started having all sorts of problems with first layer adhesion. Since I’ve been using 3DLac on my glass build plate, this has never before been an issue. Try as I might, I just couldn’t get beyond the first layer which was a horrible stringy mess and refused to stick to the build plate. I won’t go into details of what I checked as it would be a long and boring read, but finally I decided to take a look at the nozzle itself. This is Diamond hot end, so it’s one great lump of brass. This is what I found.
That used to be a nice, round 0.4mm diameter hole. Here is another picture
That is a 0.8mm diameter drill bit inserted into what was once a 0.4mm diameter hole.
The nozzle has done many hundred of hours of printing but never with any abrasive filaments. Mostly just PLA. Of course, not every print has gone perfectly and there have been occasions when the nozzle has scraped across the previous layer.
I don’t really know what caused it, just general wear and tear I guess but the issues I had with printing were not a gradual process. One day all was well and the next day all was far from well.
I had a spare which I have fitted and now everything is back to normal. So I guess, if things go awry and you’ve checked all the obvious, take a look at your nozzle……….