Continous flow pan port plugs?

[Birddog]

I'll be using a Mason 2x3 with a continous flow pan for the first time this season. I've read that a person should plug the opening between the dividers when done for the day to keep the "gradient" between channels. What do people use for these "plugs"?

Thanks for any input?

[Ausable]

Hi Larry - Although I use tapered plugs and collars on some of the dividers on my homemade continuous flow pan (pans) I hesitated to answer - hoping someone with factory made continuous flow pans would jump on your post and explain it all to you. Now that I understand how a basic continuous flow setup work and have boiled on mine for four seasons I have a big problem - I have never saw a continuous flow pan - other then my own - except one many years ago - when I had know real idea what was going on or what I was looking at. I understand there are also gates for the same purpose. I would be glad to explain to you what I have and how it works if You are interested. Just holler. -----Mike-----

[SeanD]

It may not be worth the extra effort and cost. It's a lot easier to establish and maintain a gradient than you think. That said, I will say that I still take a picture of it at least once per season.

I have a 2x3 back pan and a 2x3 front pan. At the end of the night I flood both pans up to 2" and and then shut the back pan off from the front with a valve. So my front pan is like your pan.

I don't close the gates in the dividers in the pan. I just let the front 2x3 pan mix together. The next time I get going, I slowly open the back pan back up as the front pan comes to a boil. The gradient is reestablished in about 10-15 minutes and I'm right back where I left off. I'll even add that my dividers are tack welded in, not continuous.

The other factor is cleaning. When I have a couple of days between boils, I drain the front pan to clean it. So, it all gets mixed together again anyway. After I clean the pan, I pour the sweet back in and fire it up. Not long after I open up the valve to the back pan, I have the gradient again.

Give it a try for a boil or two, then see if you need the plugs.

Sean

[eustis22]

how are you cleaning it, vinegar/hot water?

[Ed R]

With a pan that size I doubt that you would need to plug it. Just draw off some "sweet" at the end of your boil then add it back in after you have a nice rolling boil when you restart.

[Ausable]

Larry - I think You have received good advice. I was slow about saying much as I have know idea how many sections a Mason 2x3 has. I would guess 3 or 4. If You are also using a sap preheater of some kind - You might locate an isolation plug or gate in a center divider or the last divider. That said - I have a homebuilt - flat bottom 2' x 5' continuous flow. I use two isolation plugs and my pan has two sap sections 12' x 24 " and 3 syrup sections 8" x 36". The divider openings without the plugs are 1 1/2" square. The isolation plugs and collars are round and 1 1/2" across and are located between the last sap section and the first syrup section - and between the second syrup section and the last syrup section. We welded flat stock handles to the back of the plugs to make them easier to use and to insure they stay in place when needed - welded flat stock behind and back on the plug so it can be inserted and removed but when inserted - held in place with a wedge - LOL - Hey it works. My Son - who is a machinist - came up with the tapered plug idea and did all the fabrication. My Grandson - who is a very good welder - welded it all together and not a single leak to this day. Our biggest problem was ignorance of continuous flow evaporator pan design - So we all dug around for any information we could find and came up with the rig I use. It has some shortcomings - but I really like it as I only make between 8 to 15 gallons of maple syrup. Being able to pull the fire and keep my pans sweet does make the next startup faster. Much quicker than Batch Boiling as I did for many years. -------Mike-----

[Birddog]

Thanks to all for the good advice. I wish I had some welding skills, I'd just fabricate something to plug the gates. How water tight do they(gate plugs) need to be to do any good? Would it be safe to use either a piece of copper or aluminum for a gate plug? Maybe just draining it and adding it back in after it starts to boil is the way to go. So far all I can do is watch water boil - lol

[Ausable]

Ed R gave You good advice. If it will be awhile before I can boil again - say a week. I'll scoop out the partially boiled sap, halfway syrup and almost syrup and place it in separate marked containers. Cleanup my pans and cover and use it when I'm ready to crank up again. The reason for the plugs is to keep things separate as it will all blend together as the sections cool if left inter-connected. The idea is to save some time on the next boil. On starting off - a continuous flow is nothing more than a big batch pan as the whole thing has sap in it. As You boil and boil some more - things begin to change as the water boils out of the sap and you add sap in your first sap section to maintain level. In the Syrup sections the sap is changing color and foaming up or forming large shiny bubbles in the last syrup section. time to draw some off - into a test cup and check with a syrup hydrometer. If You have an automatic drawoff (I don't) it does it for you. To avoid all of this on the next boil - We leave the pans "sweet" so we can start where we left off. ----My Plugs do not leak by - Usually as things cool down and the isolation plugs are in place - it becomes necessary to scoop things forward to have a safe level prior to leaving things unattended. Once the fire is out and things cool down - I cover my pans - that are left sweetened - to keep out insects, debris, or worse mice - if about. It is hard to say - You must do this and that - as all our rigs are different. But - We can all make Good Maple Syrup and have Fun doing it. -----Mike-----

[maple flats]

I also don't plug, in fact most often, when I return the next day I draw the syrup pan totally,push the remainder to get it out and then I clean the pan (or this year I'll swap pans as I bought a second 3x3 front pan). Then I pump the blend back in and start a fire. I usually am at draw off temp in about 30 minutes, the gradient is re-established.
A few years ago, I attended a seminar session by Glen Goodrich on this. He had a method where he drained from both sides at the same time (into 2 different pots, (pot A is most dense, pot B is least dense), until he had about 1/3 of the total in each. Then he drew the balance into a third pot (C). After cleaning the pan, he reversed the flow by adding pot C in the center first, then pot B where he was now using as the infeed box. Then He added pot A at the draw off box. He then started the fire. I used that method 2 or 3 times but found it to be unnecessary on the 3x2 pan I had at the time. Now I just do as I described at the top of this post, the gradient sets up rather fast that way.