How much sap til draw off.

[Ryan August]

Hey, just curious if anyone has a educated guess. I have a 2x4 pan, 3 passes. I run 3/4 to 5/4 inch depth. How may gallons of sap do you think I need to run thru till I start to draw finished product. Last years seemed like I was close at about 70 gallons. ANy ideas?

[Urban Sugarmaker]

Here is a link to Big Eddy's explanation. If you do some more searching on here you might find more.

http://mapletrader.com/community/showthread.php?15663-Calculation-for-Sap-before-draw-off&p=174567#post174567

[wnybassman]

Hey, just curious if anyone has a educated guess. I have a 2x4 pan, 3 passes. I run 3/4 to 5/4 inch depth. How may gallons of sap do you think I need to run thru till I start to draw finished product. Last years seemed like I was close at about 70 gallons. ANy ideas?

Based on that information I would guess around 70 gallons :)

[Ryan August]

thanks wynbassman. The 70 gal seemed close but always needed to finish a little bit more on the propane burner. I think my pan thermometer may have been mis calirbrated. Operator error? At one inch on the math from the link listed is puts me about 100 gals of sap. At one inch I have just about 5 gallons liquid in the pan. So I think I may work on the thermometer and be more patient this year.

[wnybassman]

I think the biggest factor would be sugar content of sap going in. 1.5% would be greatly different than 3%. Keep boiling until the hydrometer says it is ready to draw off.

[mellondome]

thanks wynbassman. The 70 gal seemed close but always needed to finish a little bit more on the propane burner. I think my pan thermometer may have been mis calirbrated. Operator error? At one inch on the math from the link listed is puts me about 100 gals of sap. At one inch I have just about 5 gallons liquid in the pan. So I think I may work on the thermometer and be more patient this year.

Boiling point of water changes all the time. You need to determine the boiling point of water before each boil to be able to draw off by temp.

[Sugarmaker]

Sugar content being 2% then yea 70 gal.:) I just wait for it to come to temp and as mentioned, begin to draw. Are you concerned about how much sap you have in reserve? Or just curious? Sugar content would be the biggest factor. Also this happens once in the season at start up, after that we always have some syrup in process so the gallons to push it through is considerably less. We sometimes have 2-3 hours before we make the first draw on the first sap. We boil at about 110 GPH so on our rig that might mean 200-300 gallons to sweeten the pans. Yea I like 70 ish gallons. You have a 2 x 4, it boils at about 15 gph. 15gph x 5hrs = 75 gal of sap.
Regards,
Chris

[Ryan August]

thanks all
yeah really just more curious than anything. WOuld like to eventually get away with drawing off finished product and sometimes I get in patient and cant beleive how much sap I put in and still have not drawn off. The hydrometer always tells the final story of when it is syrup and ready to go to bottle.

[Noah's Ark]

I also have a Mason 2x4, I would say the 60-70 is a good number. With the blower, good dry wood and preheated sap you can boil a little better than 15gph but not really consistantly. I don't like to start up until i have over 100 gallons on hand. Kind of a waste of wood and time to get it to a good boil then shut down because i am running out of sap. I use the temp as a good gauge to start checking with the hydrometer. Last year was my first year with the evaporator so take the 60-70 with a grain of salt from me. It seemed like the first run of sap was a higher sugar content last year and I remember drawing a little sooner than I thought I would (closer to the 60 gal mark).