homemade piggy back pans

[cshaw]

Have a homemade 2 x 6 drop flue pan and have last year's 2 x 6 homemade
flat pan. Want to use the flat pan over top of the drop flue as a preheater.
Any thoughts on how to do that ? How would you make a drip or catch plate
to collect the condensation inbetween the two pans ? Any information greatly
appreciated.

[Mike Czok]

The united states department of agriculture forest service had a great pamphlet on how to build your own pre heater that might answer your question It's easy and inexpensive and works great . I believe the pamphlet number is mr#442

[mfchef54]

mike,
Do you have a web site for that pre heater?

[Jerome]

mfchef54 try this one I think it is what you are looking for http://nrs.fs.fed.us/pubs/4640

[birdmancf]

Reading that will be an easy way to get back to sleep when plans of sugarin' are keeping me awake.

[cshaw]

Thank you for the link on the pre-heater. Do not have time to make the
copper pipes,etc this season. If I can make something to hold my old flat
pan above my drop flue pan, what would the recomended distance between the two plans be ? And would I slightly tilt the top pan for the condensation
to drip to one side of the pan or am I better off putting a catch plate inbetween angled to slant the consensation run off ?

[Big_Eddy]

If it were me - I would make a simple Angle Iron frame that supports your flat pan about 2" above the flue pan. I would make one side 1/2" higher than the other, and I would offset the flat pan 1" to the low side. That way the condensation will run to the low side and drip off to the side. You're not going to lose any heating effect as a result of 1" offset, and a 1/2" difference in height in a preheat pan will have no effect.

A shield under will just reduce the pre-heating. You can still collect the runoff water if you want it by putting a collection tray under the low edge.

If you then cover the flat pan - this is likely going to be almost as effective as a fancy tube preheater - especially if you have baffles in the flat pan. With baffles - I would run about 3/4" deep on the deep end or inlet and 1/4" on the upper side (outlet) to get nice hot sap exiting. Without baffles - I would run 2/3rds full to minimize the mixing effect.

My 3 cents.

[Smitty]

mfchef54 try this one I think it is what you are looking for http://nrs.fs.fed.us/pubs/4640
That is a great web site, any one looking to build a preheater, they should see this.