If you check the crafting forums there are a lot of theories about HQ synths and how to enhance the chances of getting one. There are several consistent theories (please keep in mind this is a summation of what I have read, and is not meant to be construed as actual fact. Nobody, in fact, knows EXACTLY what all these factors do except SE):
1. To HQ more often, you should craft on a Full or New Moon
2. The day of the week matters. To summarize the most popular theories:
a) Crafting on the day with the same element as your synth=fewest breaks
b) Crafting on the day your synth element is weak against=more breaks, but more skill-ups.
c) Crafting on the day your synth element is strong against=more HQ synths, but less skill ups.
3. There is a theory that facing a certain direction enhances HQ chances. Each avatar has a certain direction in the constellation chart, so you should face in the direction fo the avatar that matches your synth.
4. The more you are above a recepie in level, the more common the HQ synths. This seems to cap at a certain point, which is about 50%.
For me theory 4 is the only one I can verify is at least close to accurate. I am woodworking 67, and I can HQ arrowwood lumber (a level 2 synth) about 50% of the time. These can be HQ 2,3 or 4. I have not noticed a significant increase in my HQs since I hit 50, which would seem to bear this out. I generally don't get too many HQs on a synth until I am at least 20-25 levels above the recepie. I'll see them, but they are pretty uncommon.
The others theories are interesting but I don't know exactly how much they play into the equation or not. They may have a lot of influence, they may have a little, they may have none. I do seem to notice more HQs using the days of the week theory than on the directional or moon theory, but I haven't written anything down so it may only be perception.
Hope this helps!
Edited, Sat Jan 29 13:48:40 2005 by widenorg