How far 25' of copper goes.

[TerryEspo]

Playing around this eve with the kids out back and in the garge after supper, I took a few pics of things.

I quickly wrapped 25' of soft copper around my 6" pipe, 14 wraps is all it does.

Specs,,,3/8 soft copper, and that is a 12" long stove pipe. I thought I would need a 24" long for 25 feet.

Just an FYI if anyone wants to know how much they may need /want when doing a copper coil preheater.

7045

Terry

[maple flats]

It is very possible that many wraps will boil sap in the tubing.

[TerryEspo]

Hi Maple Flats....Last year I had the same copper but only 6-7 wraps, not insulated, old arch. The sap coming out was warm but not hot. That is why I went with new longer, plan on insulating, this year.

I hope you are right though, cause I can shorten it if needed, easier than making it longer.

How does a guy know if it IS boiling in the tube ?

I need to get the arch outside and really do a test boil before our sap here runs.

Input and/or criticism welcome. Its all helpful to me, lol.

Terry

[flying squirrel maple]

We had sixty feet tightly wrapped around six inch pipe with a seven inch over it only way we kept it hot was to throttle it back with a small valve before it dumped into the pan, but there was a fine line between hot sap and vapor lock😵

[TerryEspo]

Flying Squirrel,,,can you explain that differntly please.

I dont think I understand. You had to keep it hot how? Throttle back to fire? LOL, I dont get it,,,so sorry. Was 60 feet too much or you wanted more than 60 feet?

Thanks.

Terry

[flying squirrel maple]

Sorry throttle back the sap flow. If we left it to free flow the sap came out warm not hot so we just slowed the flow but like I said fine line between 180% and vapor lock.

[Ren]

Hey Terry, do you have a vent in the tubing between the stack and head tank? I once got side tracked and had sap start to boil in my tubing. It shot out of my vent with so much force that it hit the roof of the shack sending boiling sap everywhere. Not to mention that it sounded like a 12 guage going off. I will never do that again!

[flying squirrel maple]

The only problem with slowing the flow down was the rate of boil was faster than what was going in so when we started to get low in the pan we'd have to go wide open which would slow the boil way down

[TerryEspo]

Hi Guys,,,,no Ren, no vent, but could for sure if needed.

Flying Squirrel, thanks for clearing that up for me. I am shocked that 60 feet didnt get your sap hot on wide open.

Were you useing larger than 3/8 copper? If I rember right last year my 6 wraps around the 8" pipe (10-12 feet) on a slow fairly slow drip just got the sap kinda warm, not insulated,,,,slow drips though as the arch only did about 6-7 GPH.

I am sure how high the copper starts and stops on the pipe would matter also. The lower down, the hotter the pipe and copper will be.

Test boil needed.

Thaks to all.

Terry

[Ren]

I would put a tee in somewhere between the stack and head tank. This would allow any pressure to be released in the case of a moment of forgetfulness.Lol

[TerryEspo]

I will have to keep the vent in mind.
I really want a test boil to see what I need to do.
The vent wil be easy if needed. I love fooling with it.

Terry

[Spartazoo]

Newbie question... Are you guys wrapping this around the stack as a way of pre-heating the sap? Interesting...

[DonMcJr]

Just remember...I have one of them lazer Thermometers and my stack just above the Pan hits 500 Degrees F.

[TerryEspo]

Hi guys....spartazoo, yes, the copper tube is a cheap preheater,lol.

DonMcJr,,,,get that lazer and pointer at yer car/truck engine, lol,,,its got lquid running through it.

The key is the liquid is flowing. Last year I had the same set-up and the sap didnt get really really hot, yes it greatly improved it, but I want to tickle the dragons tail and get it close to 180 if possible.

I am thinking no insulation and 25' copper first test boil, then if I need hotter, will insulate that copper, if I need hotter still, add more copper and insulate. I highly doubt I will need all that.

I will get pics when I test boil.

Terry

[acerrubrum]

I've been thinking about doing the same thing as Terry. I think I remember hearing some formula someone had for doing this coil wrap but not sure. I gotta believe someone knows how many wraps in a given sized soft copper tubing for a 6 or 8" stack would get the sap good and hot, but not over boiling.
Anybody figured this out?
The boiling sap geyser gives me pause though!
Pat.

[TerryEspo]

I am not worried about vapour lock or boil, all we need to do it move the barrel that feeds the copper away a bit, or straighten the copper to run along side the pan and then drip, or snip a few feet off the drip end. No biggie in my opinion.

Test boil will give me the answer. I just want it hot coming out, all should be fine.

Terry

[Shiftman]

Hey All,

Interesting stuff. I have just fabricated a similar heat exchanger. Can wait to try it out. I have installed a damper on the inner smoke stack. When I got a hot fire I close the damper which forces the exhaust air out some perforations I have cut inbetween the two exhaust stacks; causing the exhaust air to directly contact the copper tubing. 71577158

[maple flats]

Look at the pictures of Johnny Cuervo's pre heater. He can control the temp by adding or removing springs to hold the loops against the stack. He has a real neat set up. Link: http://www.flickr.com/photos/57535094@N00/sets/72157601539320490/

[TerryEspo]

That is a neat set-up for sure.

I guess you would have to constantly check to temp of the sap before you adjust the springs though. Then once adjusted, you would need to check again to see if you need to re-adjust, lol.

Tomorrow is my test boil and I will see the temp with a large fire and blower going, when the fire gets lower, I will know the sap temp is lower. I will have a soda instead of adjusting too many things.

I wont fire that idea though, I wont know till I try my own set-up.

Thanks.

Terry

[wildlifewarrior]

How many gph do you think this could add to a system? 2-5gph?

Thanks
Mike

[jrgagne99]

Ren, How much depth did you have in your head tank? When mine starts to "boil in the coil" (I always say this like "Bungle in the Jungle" by Jethro Tull), I can hear it venting water vapor up through the head tank. In essensce, the head tank is a big vent.

[TerryEspo]

I think I read here at Maple Trader that preheated sap helps not to kill the boil and adds about 1/2 GPH to evaporate.

Please someone correct me if I,m wrong on that.

It seems low, but over hours it adds up, kinda like the drips from our wonderful trees !!


Good luck.

Terry

[ForFun]

Terry,

I am in the process of doing this same copper tubing 'pre-heater'. Just curious how your test boil went and what the temp was coming out of the tubing..

Thanks,
Keith

[TerryEspo]

Hi Keith:

Well, no easy answer,lol.

I have not had enough sap to really give good facts yet.

But, I will say it will work. I think I need to insulate the copper coil if I get a good 50 - 100 gallons at once to boil.

My problem was that in order for the coil to supply the amount of sap needed to replace what I was evaporating the sap was not hot, If I slowed the flow down to have the sap hot, it was not fast enough to keep up. In a way thats good, it means my machine is boiling real good, but I want hot sap.

If I remember right, if I allowed the copper line to fill as fast as it could, wide open, that was a bit too fast, I did have to slow the flow down a bit.

EDIT......I also played with a divider, just sits in pan, not welded, just palce it anywhere I want. I put it at the last 3" of my 58" pan, the boil stopped at 55" but cold sap was coming in at the last 3". That worked fine for me too. END EDIT

I need another good sap run to really fine tune the copper pipe.

I will make to 25 feet work, just finding out what works best.

Terry

[ForFun]

Thanks Terry for replying.....

That was my first post on this site, AWESOME people with GREAT advice.
I've been reading forums on here since the summer of 2010 and that is when i decided it would be a great adventure to do with my father who had just retired a few years earlier. He has 100 acres of hardwoods and loves being out at his "land". Figured he could boil during the day and i would stop out and help finish when i got off work. I purchased 50 taps n pails in February of 2010 and was pretty pumped up to get started. Well, my dad ended up having a severe stroke early in the middle of March just when we were gonna start tapping. That ruined everything...but i still went out and tapped about 20 trees just to do it and it gave me something to tell my dad about when i visited him in the hospital. I started cooking sap down later that month on a turkey fryer in my driveway and was timing about how much would boil off in an hour and kept adding and adding all day. I figured i would add again one more time, fill it up and head up to the hospital to visit my dad. Figured i had plenty of time to visit. Well, the first thing i learned is that the sap in the fryer gets more and more concentrated as i added and cooked, thus not taking as long to cook down as it did earlier in the morning. When i came home from the hospital, and turned in the driveway, all i could see was nothing but a pile of glowing, molten aluminum burning on the driveway......Needless to say, my first year at this was a complete Disaster!!! I still ''putts'' with it on my own with my 2 daughters, have about 75 taps/bags this year and cook on a 2x3 pan over a concrete block arch. I don't have a chimney pipe, so the smoke from the fire just kinda billows back into the sap and gives the syrup a hint of smoke flavor. Everyone else likes it, but i'm not all that crazy about it so this year, i will have a chimney coming out of the blocks and plan to make the copper pre-heater so that i can contentiously add hot sap slowly instead of adding it cold. Hopefully this will cut down on the hours i'm out at the 'land' cooking down.
Sorry for the 'winded' reply, but i just wanted to again thank you for the quick response!!

[TerryEspo]

Hey FORFUN:

Winded replies are welcome here at Maple Trader, bring them on.

Your reply is full of emotion, I hope you dad is fine, man that must be hard to deal with.

Great you have your two daughters involved, they will always remember these times with dad.

I admit I giggled a bit about the molten aluminum !!!

75 taps is a pretty good number to work with for not really being into it that much, good for you.

The copper preheater will work for you I am sure, a 2x3 pan will not outrun your copper feed pipe. And, for sure get a stack of some kind just so you can stand close to the boil and enjoy the smells and sounds !!:lol:

Good luck and keep us posted, we all love pics here too.

Take care.

Terry