For a high boiling water insoluble organic oil (unsaturated ketone) what would be a good ratio  of solvent to expected product. Haven't used DCM much so not really familiar. It seems almost like chloroform. Have been using about 3ml per ml. Did a couple little terts and it seems this may be way too much. Is there a rule of thumb to use?

You don't really need much in this case. If it's a water insoluble ketone and you're extracting it from an aqueous phase, then you'll obviously be able to separate some of the ketone without a solvent, then just extract the aqueous 3x with a small amount of solvent.

You're talking about using like 1ml organic / 5mL aqueous... the best way to find these amounts is by trial and error. Keep track of your yields!

OK, Chromium thanks for the help. My CRC handbook does not show any azeos with DCM. It seems there should be some. Especially chloroform I would expect. Also this stuff absorbs acid like crazy. Aqeous phase is 50/50 v/v acetic acid. Should the acidity be neutralized before distilling off the DCM or is this just a waste of time? The product is the high boiling (250deg @760mm) ketone. I do want to reclaim the DCM. The last time I did this procedure I used PhMe and went straight to distill w/o neutralizing with no problems. But then PhMe forms a binary azeo with water. Anyway I know this is rather incomplete information to go on but any advice is appreciated.

By the way I extracted 5L liquor with 1.2L total DCM. 600/300/300ml increments. The third extraction had almost no detectable product using my rather crude analysis technique.

After extensive searching, damn I wish there was a library around here, here are the common azeos of methylene chloride which are sure to be helpful to many.

30.0%  acetone     57.6 degrees
11.5   ethanol     54.6
30.0   ether       40.8
8.0    ipa         56.6
7.3    methanol    37.8
51.0   pentane     35.5
1.5    water       38.1