"mtshine,

When you do a reflux run the fractions should have more distinct boundaries. If you run full reflux for 45 minutes (or more) at the beginning of your run, and you're not using excessive power, and you draw off heads slowly, you should be able to detect the end of heads with your nose alone. But if you're collecting in multiple jars (highly recommended) it doesn't really matter since you won't be making cuts for another day or two anyway (after airing). The only reason it would matter is if you want to increase your collection rate once you're in hearts, which is certainly valid.

When I say draw off heads slowly (after equalizing), I'm talking just a few drops per second. When I started out I would do three things wrong:

1. I used far too much power.
2. I didn't let the column sit in full reflux long enough.
3. I drew off heads way too fast.

Once I corrected my technique I was able to get a pretty good compression of the heads, and this made the heads cut easy to find. Without equalizing and drawing off heads slowly, there was more smearing ... so it was sometimes difficult to decide where to make the cut. And if I got greedy, I'd end up having to run it again.

In any case, I never run the rig based on temps. I record temps. And I watch for changes as clues to what's happening. But I never use them as a basis for making decisions. For me, it's all about managing power and collection rate. So that of course means that I don't use temps to make cuts during a reflux run. The nose and palate seem like much better tools for that job ... and they both work better after a day or two of airing and diluting a sample to around 30% or lower.

Regards,
--JB"

Indeed...X2, even - I now use the same logic for all. Stopped basing it off temps and rely totally on small jars, nose and a few days time to tell the tale. I was unsure at first because I'd read so much about temps and crap, but once I tried it, I was sold on it. I record temps too-for each jar, but only for reference later.

Thanks for the reply JB,

Operating temps,
I usually use the temps to give me general conditions; I was hoping that temps might help me make cuts; it appears that the temps just get you in the ball park, and experience makes the game worth playing,

I used to drink beer and wine and left the spirits alone; it's time for me to get out, as was suggested by others, and try the various spirits on the market, I guess that's some experience I might enjoy,

Reflux time,
I usually run in reflux around 30 min. I placed a thermocouple about 12 inches up from the base of the column. By the time my head temps gets up where I need to be concerned, I dump it into reflux and it takes about 30 min to get the column temp down to ethanol evap. temps. I think now that you mention it; 45 minutes would just fill the column further down. Hope I'm making sense,

Collection rate,.
My collection rate can be frustrating, the ball valve is a pain in the ass,, found a needle valve today on eBay and hopefully future collection rates will be predictable as appose to chance and a lot of fooling around.

Breathing time,
Been letting it sit under a coffee filter for 24 hrs, read that somewhere, now that I think about it, I forgot about a batch and after three days, I checked and it seems to me that there was an appreciable difference. I'll extend the airing out session to 3 days and then let the nose do its work,

Collection volumes,
Been collecting by the pint after the fores, will start collecting in 1/2 pints for the first 2 pints, should be thoroughly in to the heads by then and will make the cuts in the first 1/2 pints,

Thanks again for your input JB; I appreciate your assistance,

MT