help with flow

[mcsap]

This is my first year using a pan with partitions (second year overall). How do I establish and keep a flow going from back to front? Today was the first boil and it seemed like I always had the 2 middle partitions with the hottest boil (out of 5) and front always seemed to slack off. Was my fire simply not hot enough?

Also, with a 5 section pan like this (2.5 x 4 feet), should I be able to draw syrup from the front, or near syrup, or should I finish on a separate burner? That's what I did tonight, time for bed now :?

Thanks,
John

[ibby458]

We used a 2 1/2 x 5 partitioned flat pan up until this year. If you keep adding your fresh sap on one side at the biggining of the channel, your syrup will come off the opposite side. Everytime. (If your partitions run lengthwise. If they're sideways, adjust these suggestions accordingly)

Is your arch bricked? How is it made? WE had that problem the first year. THe fire would roar up the center, making the middle channels boil like crazy, with few bubbles in the side channels. THere's 2 things that may help. Keep pushing your fire to the sides of the arch, and fire in the center with your fresh wood.

My arch had a section in the back that "collected" the fire/smoke, and funneled it to the stck. Instead, the fire just roared up the center and out the pipe. I found a rock just big enough to fit under the pan that blocked off a good portion of the middle of the smoke path, forcing it to go around to the sides before getting out. I was using forced draft, but if you don't, be careful you don't block off TOO much draft. We used stove door gasket rope as a seal between pan and arch. Ceramic blanket strips are even better, and help a lot in keeping the sides boiling.

We also found that it helped ALOT to preheat the sap. For a couple years, we put an all metal chair tight to the arch on both sides, and put a stockpot full of sap on each side, always topping off the arch with the hottest sap. ((Later on, I got lazy and used a pump to put sap in cold. Less work, but it did slow things up in the boiling department)

Lastly, we found it was helpful to keep the sap level as low as you dare. I ran it only 1/2" deep. My wife is braver, and kept it closer to 1/4". (Pan HAS to be 100% perfectly level in all directions.) Boils fast, but there's no margain for error. I must admit that she's never burned a pan, but I did. Twice.

We always cooked it a couple degrees PAST syrup, but continued to draw off until it was a couple degrees UNDER syrup. THey mixed in the bucket ans was pretty close. We always filtered it twice, the last time to a pan on the kitchen stove for adjustment and reheating for canning.

Good Luck!

[mcsap]

Thanks. Sounds like I wasn't being brave enough. I was reading some of the other posts about sap depth and thought I should stay above an inch to be safe.

I wasn't sure if I needed to draw off some sap from the front once the boil got going to establish a flow or not. I'm using an old oil tank as an arch and I cut a barrel in half and put in the rear to kind of get the "arch" effect. Seems like I need to make the fire in the front bigger and hotter. I've got enough sap (after collecting this AM) to give a try again today.

John

[brookledge]

John
Youare not going to really see the flow in an evaporator that size. Just as ibby458 said continue to add the sap in the same location and as it is concentrated it will work its way to the end. Having the middle sections boil real hard is ok because the last section it is better to have alittle less heat. That section is where you draw off and tends to foam up more. So a little less heat is ok on the side.
Also I don't know if you are able to reverse your flow but you should do that as the nitre builds up in the last section. By reversing the flow the nitre will be kept to a minimun by the raw sap which tends to disolve most of it.
Keith

[mcsap]

Thanks Keith. I thought I had it going OK today, with a good boil in the front part and middle sections; then I tried levelling up the pan a little, got distracted and burnt the middle section. Bummer. I wasted a bit of sap and the best part of the day. I guess I'll try again later this week after a bit of scrubbing.

My pan is partitioned from front to back rather than side to side, so I run sap in the back end and draw off the front. I'll get the hang of it yet.

John

[maple flats]

My 2 x 6 has a flue pan and a syrup pan and I have drawn near syrup off in the past. This year I have drawn syrup off continuosly however it is a mighty fine line for flow. On my set up I often get a faster boil in the 2 center sections than the outer 2. Only when every thing is perfect does it even come close to looking like a full boil in 7 of the 8 sections on my rig with the section being filled from the preheater showing a slower boil but still a boil. The drier the wood the better it boils and most of mine is the best i have ever used but a little wood still has room to improve on dryness for future seasons. I have already started cutting for next year but have not made much progress yet. It would be best if all was cut now for 07 and even 08 for that matter.

[ibby458]

Sorry to hear you scorched your pan. I hope it wasn't damaged. I found that a Mouse sander with a scrub pad installed instead of sandpaper helps a lot to get it clean again.

We had our flat pan on an oil tank arch one year. THe fire ran too far under the pan to get a good boil. We filled the back half with dry sandstone, covered with sand until it only left an inch of so under the pan for the fire/smoke to get out. That worked, but held a LOT of heat. Make sure you have plenty of sap on hand when you start shutting it down.

No matter what you boil with, every unit has their own quirks. Keep at it, and you'll find the best way to keep yours doing it's best.

Good Luck to you!

[mcsap]

Thanks for the encouragement. The pan wasn't ruined, I just learned an easy lesson the hard way. :oops: I might do what you described for next year and build up the back of the arch a bit more. Actually, the half barrel I stuck in there seemed to be getting the job done in terms of channeling the fire under the rear of the pan, but there was still a gap of about 6 inches or so.

I think part of my initial problem was one of expectations. I thought the sap in the front pan would concentrate faster than it was. Now I can't wait for the weekend to give it another try! At least I've come up with a few questions to ask. Seems I always have to get into something before I really find the right questions.

John

[WESTVIRGINIAMAPLER]

John,

Mapling is always a learning experience no matter how long you do it. You just try to learn from your mistakes as experience and mistakes are the best teachers.

You will have it roaring and the longer you work with it, the better you will get at it! :D

[ibby458]

Oh Yes. Flat pans can be frustrating in their speed of boiling. It wasn't unusual for us to boil for 4-5 hours before the first draw-off. (Starting with a clean pan and cold sap.) It's a bit quicker if you shut down with some near syrup left in the pan to start with the next day, but it'll never approach a real evaporator with flue pan. (Although that can be frustrating to get the first syrup off, too.)

Hope your trees are running better than mine!

[mcsap]

Thanks for all the encouragement and insights. Finally had some success today--actually drew off some syrup! :D Yes, it did take about 4 good hours and it wasn't all that much since I had to leave enough sap to shut down, but it worked with no burning of the pan.

Haven't had much sap this week and nothing ran here today, never got above 30 and was windy. This coming week looks good, but of course, I'm tied up next weekend until Sunday afternoon :? . But, I can take off that Monday, should be filled to capacity by then.

Hope you guys are doing OK.

John