In regard to Owen's question as to the heatgun distance from the green 
coffee beans, I start off by holding the aperture of the heatgun about one 
inch from the beans during the initial stages of heating.  As the roast 
progresses and I start to ramp up the roast, I hold it within about one half 
inch and even plunge the barrel of the heatgun into the bean mass and stir 
on occasion.  I move the distance of the heatgun from the beans back and 
forth depending upon the progress of the roast: too fast, and I move it back 
out a bit; too slow, and I move in closer.
The appearance of the beans and the sound of the cracks will be your best 
bet to gauge your progress.  You clearly do not want to scorch the beans by 
moving things along too fast.
A couple of other tips: I use a 64 oz size bowl for most of my roasting.  
This gives me a lot of surface area, so the bean mass is not too deep.  I 
believe this helps me to achieve an even roast and gives enough space for 
bean movement.  You should periodically check the aperture of the heatgun to 
ensure it is not clogged by chaff.  if so, a quick blow should remove it.  
You should not point the aperture directly at your face while it is blowing 
superheated air (insert smiley here).  In the Seattle area, the Wagner HT755 
is available at Lowe's Hardware; Home Depot carries the Milwaukee model, 
which is simply a rebadged Wagner HT 755.http://www.coffeegeek.com/forums/coffee/homeroast/23213are some of the discussions about this method on Coffeegeek.com that contain ">http://www.coffeegeek.com/forums/coffee/homeroast/28030http://www.coffeegeek.com/forums/coffee/homeroast/28975http://www.coffeegeek.com/forums/coffee/homeroast/23213are some of the discussions about this method on Coffeegeek.com that contain 
some good tips on technique.  Please let me know if I may be of any further 
help.
Michael G. Lloyd
Mill Creek, Washington  USA
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