My earlier revelation that I had solved the extruder jams I was experiencing with filament produced by my Filastruder were premature.
I have had all my subsequent prints fail:
Here the extruder jammed.
And here it jammed, after putting down several poor quality layers first.
I was getting a bit disheartened by this stage. Then I realised that I had been extruding filament from some random ABS pellets I bought from ebay. I had got 5Kg from CraigRK on emaker some weeks before, so I decided to try these pellets instead.
What a difference it made. The filament produced was much smoother and did not feel as brittle. And the first print I did came out as good as any I have made with commercially produced filament.