Newby is back with boiling questions.

[wmick]

I appreciate the insight... Thanks.
I find it interesting, that with such an ancient art... there is still lots of room for theorizing and creativity.
Sure hope we get a few more votes though.... Tied up at two at the moment...

Fingers crossed that I might get enough sap to try one more boil this weekend...
Pretty sure I could pull off a pan modification between now and then...

[Russell Lampron]

Option 3 works for me. My front pan is set up like that but I have draw off/float boxes on my pan and I just swap the float from one side to the other when I want to change sides.

[Super Sapper]

I vote option 2, this will get the draw off channel over the hottest part of the evaporator. Running the other way you have a larger portion of your last channel sitting on the rail reducing heat transfer.

[Big_Eddy]

Mine is option 1. My last channel boils just a bit softer than the middle syrup channel, but I like that because it makes the whole evaporator less touchy. I never make syrup anywhere other than the last channel. I run pretty shallow (3/4") if I'm just boiling. A little deeper on a "work" from home day.

Looks like you now have some of all versions covered.

[wmick]

Anyone Care to Weigh in? Whats your favourite?
Thanks

Attachment 19932

#2 or #3 were my picks... As the response was not overwhelmingly weighted in any one direction, I'm going to take a chance on #3. A quicker and easier modification for me, as I wont need to change my pan-to-pan pipe, which has special milk-line fittings. I just need to add a couple 1/2" fittings for my thermometer and the draw off valve... and tack in some new dividers.... Should be quick.
Will let you know how things work out... It will be nip and tuck, whether I have enough sap to start a fresh run this weekend..
Thanks Again

[Sugarmaker]

I like both these and both should work and maybe even a little better than the current front corner draw off. depending on your pan construction and ease of changes could determine which way to go. Good luck!
Regards,
Chris

[wmick]

Just a little update.... Maybe not so little.
Did my last boil for this year... Roughly 1900L in 24 hours... so about 80L or 21 Gallons / Hr. I’m fairly happy with that... I know I could do better if I had better more consistent and smaller split wood... I burn a mixed bag of dead fall and culled trees.

Started up about 8AM Saturday, with clean pans and about 2/3 of the sweet from my previous run. I had finished off some of it, thinking I was done for the year, but changed my mind.... I poured the partially boiled sap into the syrup pan from the front, while the fresh sap was pouring in from the back end, attempting to simulate the gradient a bit... Not knowing the density of my mix, I was guessing at how long it might take to sweeten the pans.

I went with #3 modification on my syrup pan... and I was much happier with how the pan worked... All 4 sections had a nice rolling boil. I think that's a good thing.

I learned that my hydrometer does work. (after the fact), but seems like too slow of a process to check for syrup when the thermometer spikes to 219 in a hurry.

My temperature at the draw off went above boiling point fairly early in the run.... but it just hung out at about 216 forever??... I couldn’t seem to get it past that point.. And, Yes – I did check the calibration on my thermometer. At about 19 hours in, it quickly rose to the 219 and all hell broke loose... I had a hard time keeping the temperature down at 219... Drawing off as much as I could... The Level in the syrup pan was dropping.. and the pan seemed to be more air/foam than liquid... I was choking the fire to try and settle things down.. We survived it with no casualties except for about 18L of over-dense syrup... (all in one draw !!). Then it cooled down for a while. At about 23 hours, it happened again... except this time I was a little more prepared for it... and choked the draft back a bit right away. This, again, was approximately 18L drawn off in one quick batch. And this time I discovered a new problem..

The level in my float box was dropping slowly while I was drawing off. This likely could have attributed to the foaming/dropping issue I had the first time.... I overcame it by propping the float valve wide open.. and it was able to just maintain the level. Apparently I need some bigger lines and fittings from my tank to make up for a lack of head pressure when my tank level gets near the bottom.

So – all in all, this run produced about 36 L of syrup from the draw off,,,, and I kept about 40L of the densest sap from the pans for the turkey cooker.

I am somewhat frustrated that I haven’t figured out how to make this thing “Flow”, like I think it should… with a constant trickle at the draw off, rather than these periodic large batches… Oh well… I have 11 months to think about It… I’m sure I will learn a little more every year.. and with any luck, I will add a RO home-build to my list of complications by next…

This reasonably new hobby of mine scratches a couple itches. Great excuse to spend some time out in the bush in the non-hunting season…. My need to experiment, develop, build and improve machines and processes. And my love to share a harvest with family and friends. I sure couldn’t do it without the help and experience from you folks on this forum… What a great community. Hope you all had/are having a great season… Best of Luck.

[Sugarmaker]

wmick,
Doesn't sound like you did any thing wrong. I need to back and look at concept #3. Yes concept #3 should be good set up. You have been busy! Question did you completely seal all the partition seams to keep sap from mixing???
My guess is that your still kind of making syrup in a batch mode. My rig does that all the time. First draw is big. Then they get smaller and more controllable as time goes on in the boil but I rarely get a trickle beyond maybe 30 seconds when it has finally got all the big batch of syrup out of the system. Those initial large batches are somewhat common. It may never do a continuous flow. The term is more of a concept than a reality. The syrup is holding near the draw off until it gets up to temp. If the bubbles show that you have syrup a lot farther back in the system then the batch will be large and or the draw off temp may rise. You might try drawing off a full degree or more under temp for that initial large draw of syrup then check density and continue to adjust the set point temp as the draws get smaller and more frequent.
Just my 2 cents.
Regards,
Chris

[ennismaple]

With an elevated sap tank your flow through the float box will be higher (deeper sap depth in the pan) when the tank is full vs when the tank is nearly empty. We always need to adjust the float box as the levels drop in the head tank.

Do you have a float between your flue pan and your syrup pan? If it is just a partially open submerged valve you can get mixing back and forth which will kill your gradient. Most commercial evaporators have a float between the pans to prevent backflow and allow you manage different levels in your pans. We run 1" above the flues but 2" deep in the front pan but the sap drops about 6" as it enters the front pan.

[wmick]

wmick,
Doesn't sound like you did any thing wrong. I need to back and look at concept #3. Yes concept #3 should be good set up. You have been busy! Question did you completely seal all the partition seams to keep sap from mixing???
My guess is that your still kind of making syrup in a batch mode. My rig does that all the time. First draw is big. Then they get smaller and more controllable as time goes on in the boil but I rarely get a trickle beyond maybe 30 seconds when it has finally got all the big batch of syrup out of the system. Those initial large batches are somewhat common. It may never do a continuous flow. The term is more of a concept than a reality. The syrup is holding near the draw off until it gets up to temp. If the bubbles show that you have syrup a lot farther back in the system then the batch will be large and or the draw off temp may rise. You might try drawing off a full degree or more under temp for that initial large draw of syrup then check density and continue to adjust the set point temp as the draws get smaller and more frequent.
Just my 2 cents.
Regards,
Chris

Thanks Chris
No I did not completely seal around the dividers. They are just tacked in... This never occurred to me that this might be an important piece.... .. I can certainly seal them up for next year and eliminate one potential contributor. I certainly hope I can make some improvement to the flow/frequency... I would find it much more relaxing than waiting hours for the ensuing chaos... Unfortunate to wait for a year to test more ideas... however, I guess that's what makes it a treat.
Thanks for your help.