Can't believe it was a year ago that I started this topic. Returning to it, it looks like Dave had already looked at what I've been looking at on the last batch.
So, I've had it in my head for some years that the bulk of the conversion takes place when the methoxide is first introduced so I did a 3/27 test after the initial mix. Result was 0.7ml dropout. I usually do five mixes of around two minutes each, often over a period of days (depending on what's convenient for me) and did another 3/27 after the fifth mix. The result was exactly the same.
I ran the second stage and again tested after the initial mix and got a clear 3/27. I'm now wondering if multiple mixes are even necessary. Dave's results in the last post indicate that perhaps they are, but on the next batch I'm going to try just one mix on stage one and if the 3/27 test looks promising, go straight to stage two and test again.
I should add that the current oil is of good quality and glycerine washed. Both washing and mixing were done at ambient … currently circa 22°C. I'm using Frankinpump running against a new design of venturi ("design" is perhaps a misleading term!) which I think creates considerable turbulence and which I'll post more on when I can find some fittings to photograph.
If I get similar results on the next batch, I'll post up the details.
