Drop Flue Pan

[afretired]

I,m getting ready to build me a new arch but I am having trouble trying to get someone local that can bend the flue pan. Those narrow channels pose a big problem for most machine shops. As far as making the syrup pan and the rest, it's easy going. I'm really wanting a 2'X4' drop flue pan with 8-12, 6"-8" flues(channels). Any ideas on how to come up with one? Or how to bend it?

Dave

[brookledge]

I know you probably want to make your own but have you looked at used ones? I would think if you are paying someone (fab shop) and they don't make them every day it will end up costing more than finding one already made.
But if you do want to have one made then I'd keep looking around because the more flues you have the more surface area and higher boiling rates with out using any more wood. you are on the right track with the amount of flues you want. 3/4" to 1" is the space you should have between them
Keith

[afretired]

I wouldn't mind a good used one if the price was reasonable. One real big problem with living in central KY, there are not any used pans within a few hundred miles. I don't think the price to have the flues bent will be too bad if I can find some one to do it. I can fab the ends and TIG it myself. I've been looking for several weeks on the Internet for a good used flue pan and haven't ran across one, but I haven't given up yet.

Dave

[Sugarmaker]

Dave,
Big Eddy made a brake to bend flues. Search for it on here.
Regards,
Chris

[afretired]

Thanks for the information; the wheels are turning now. His brake was to simple, I'll have one built fairly quick.

Dave

[Big_Eddy]

I have made a flue pan too - it's on here somewhere as well. Sometime I'll need to post pictures of how I bent up my syrup pan with 8" sides using the same brake with a twist.

[afretired]

Big Eddy
I have been looking at your brake trying to get a good idea on how it works. Looking at your pictures it does exactly what I need. I'm a little confused though on how it works. Form the first set of pictures you show the scrap metal that you were practicing on sliding in through the back. I can understand how it bends the first bend up, much like a regular brake. But then in a later photo where you are actually fabricating the flue pan you have the SS metal in vertically. That is where I am confused.
Dave

[jasonl6]

Maybe you can look into an amish made pan and just weld it yourself. I know a few people that have done that around here. Attached is a local price list. Might be worth asking.

Jason

[Big_Eddy]

Big Eddy
I have been looking at your brake trying to get a good idea on how it works. Looking at your pictures it does exactly what I need. I'm a little confused though on how it works. Form the first set of pictures you show the scrap metal that you were practicing on sliding in through the back. I can understand how it bends the first bend up, much like a regular brake. But then in a later photo where you are actually fabricating the flue pan you have the SS metal in vertically. That is where I am confused.
Dave


Dave.
I folded an "accordian" shape. flat - down - flat - up - flat down ..... Every second bend I had to flip the sheet over. I bent all the flues first, then bent up the outside edges for the sides. I used a 4x8 sheet and the 8' made a ~ 18" wide pan with 6@5" drop flues and 9" sides

At all times - the long (unbent) end was to the front - so we were bending the long end up each time we operated the brake. (7' at the start - was hitting the ceiling)

To start, I had the sheet upside down with 12" into the brake (9"sides plus 3" flat before the first flue) I bent the material up for the drop of the first flue. Took it out of the brake and turned it over and made a second bend 5" from the first. Kept it in and brought the long portion of the sheet back level, pushed it back 1" and bent it again to form the bottom of the flue. Pulled it out, flipped it over adjusted 5" and bent it again. Brought it level, adjust 1", bend, then flip and repeat. For the second and future flue bottoms / tops, we had the previous flue down and spread over the bed of the brake from the rear (Hence the reason no bracing on the underside of the brake - a tradeoff between stiffness and access.) Once you got the pattern it was easy.

When I first built the brake - I used a piece of angle for the hold down. Once I got using it, I replaced that with a piece of 3/4" x 2" (2" vertical) with a 1" flat bar welded on the base. I needed the narrow hold down to get down in the bottom of the flues. Also - it needed to come off and on easily - not just lift slightly - once each flue was formed it needed to come off to remove the sheet.

Hope this helps.

[afretired]

Big Eddy
Thanks for the description and clarification. That cleared it up. I just couldn't get it in my mind the way you first described it and the way it looked in the picture. I have a box and pan brake but I couldn't get in shape to bend the flues. So I went to a large machine shop that we use at work who does a lot of fabrication, and they scratched their heads and wanted some time to try and check with some other shops. And here we have a guy in his garage builds a brake out of scraps laying around that you can pack under your arm that will do the job. Everyone is always looking for the difficult/complicated answer instead of the simple one. Thanks again.

Dave

[afretired]

Tonight I finished making the bender that Big Eddy designed. I did a trial run on a piece of scrap SS and it seemed to work fine. I used the blades off of snow plows that I had laying around. A neighbor works for the road department and had some old points that had been taken off and dropped them by a while back. They were just what I needed to use for the main parts of the bender. The front edge was even wore down to about a 70 degree angel making it posible to overbend the SS to allow for spring back. After the thanksgiving I'll go to the steel yard and get the stainless steel sheets and get started making the pans.

[Sugarmaker]

Dave,
Your flue brake is a piece of art compared to the brake I built!
I used Big Eddy's plans too, with some modifications, for my 5 foot + brake, but dialed my build back to the point I think I told folks I had about $5.00 invested. (really not sure it was that much:)) My brake was not perfect, it had some give in the middle. But I was satisfied enough that I used it for all the bends on the WRU that I built (another thread). I would not have been able to tackle that project without it.
Good luck on building the flue pan if it looks as good as the brake it will be a nice pan! Nice to have the right tool to do the job.
Regards,
Chris

[afretired]

Before I start cutting and bending the SS sheet metal I need a little advice. Sitting here in the middle of KY there are not any evaporators around here for several miles, in fact I don't know how far. To top it off, I haven't ever seen one in person, so I need some help. Right now the plan for the flue pan is to make the flues 6 inches deep and one inch wide, that's about as tight as I can make it. So with 10 flues and a 2 inch lip around the sides the pan will be 23 inches wide and I plan to make it 48 inches long.

First question: How deep should the sides be above the flues? The metal will work out good at 9 inches, is this deep enough?

Second question: Since I am making a continuous flow pan, I plan to make it with three channels. down, back and back down. Do the dividers need to be as tall as the sides? Also, will a small opening at the end (2X4) be enough for the sap to go into the next channel?

Third question: I read a while back that the sap actually seperates by density and the higher sugar content (sap/syrup) while cooking floats ontop of the lesser density sap and flows over the flues into the next channel. If I said all this right, is this true? because I cannot think of any way for the sap to flow from the bottom of the flues into the next channel.

Dave

[Haynes Forest Products]

On my store boughts the inside dividers are lower than the sides. As far as the opening for the liquid to travel from channel to channel 2X4 is fine at the flue level...............the space between the end of the flues and the ends of the pan. remember that you will close off 1 on each end and leave 1 open that will give you the continous flow. You will also have the space above the flues that allow the sap to flow thru the channels so the space is bigger....................the channel space in the flue and the space above.

As far as higher sugar content floating on the less dense that might be true when its getting hot...........I dont know BUT when things are kick a*s boiling there isnt any seperation its all mixing and moving. As long as the flues are full and there is enough sap above the fles to keep boiling and mixing things will move along. The reason it move is to fill in the low area created by the evaporation. Afretired I was confused how it all worked when I had a pan sitting in front of me:confused::confused::confused:

[allgreenmaple]

Tonight I finished making the bender that Big Eddy designed. I did a trial run on a piece of scrap SS and it seemed to work fine. I used the blades off of snow plows that I had laying around. A neighbor works for the road department and had some old points that had been taken off and dropped them by a while back. They were just what I needed to use for the main parts of the bender. The front edge was even wore down to about a 70 degree angel making it posible to overbend the SS to allow for spring back. After the thanksgiving I'll go to the steel yard and get the stainless steel sheets and get started making the pans. That is most impressive, & obviously works very well. A very well put together bending unit, my hats off to you sir.

[afretired]

I've been working on the flue pan. Here are a few pictures showing what I have been getting done. It is going well, though TIG welding the thin SS is a little more difficult than I first thought. Check out the rest of the pictures on Photobucket.

I've got to get back to work on the sugar house.

David

http://s742.photobucket.com/albums/xx69/afretired/Maple%20Syrup/Bender/

[jimbo752]

Nice pictures! Really shows how the bender works well- What is your plan for welding the ends? I assume you will fusion weld the corners, but will you use one piece that you cut out to the profile of the flues? Im going to build a similar pan myself, and am glad i found this thread, you guys have figured out a lot of the things ive been trying to do in my head- keep up the good work!


I've been working on the flue pan. Here are a few pictures showing what I have been getting done. It is going well, though TIG welding the thin SS is a little more difficult than I first thought. Check out the rest of the pictures on Photobucket.

I've got to get back to work on the sugar house.

David

http://s742.photobucket.com/albums/xx69/afretired/Maple%20Syrup/Bender/

[afretired]

I already have the ends welded in that half of the pan. I did like Big Eddy and cut individual plugs for each flue. The bender does a real good job, but to cut a single end, cut out to fit each flue, then everything would have to dead-on. Otherwise it would be a nightmare trying to weld it with any miss-fitting at all. This afternoon I'll try and get a picture on here showing the ends.

David

[Sugarmaker]

David,
Looks like the beginnings of a drop flue pan. Nice work! the brake seems to be doing the job well!
9 inches for the depth of the pan should be Ok. Especially if that works for your materials.
Lots of boiling action and very high bubbles in the flue pan so deeper is better. Front pan doesn't have to be quite as deep. 8" might work good. Most factory pans are same depth flue and front I think. My old King style has a deeper back pan than finish pan.
I have three partitions, making 4 channels in the front pan allowing the sap to enter at the rear on the right and exit at the rear on the left. Yes 2 x 4 opening is plenty big enough. Some Leader pans have flow gates at the flow through ports. I have round holes that can be plugged If I want to make a large batch of syrup.
Sap is boiled and as it gets denser the syrup is pushed in front of the sap, moving towards the draw off, or the spot farthest away from raw sap entering the system.
If you buy a hand held refractometor <$100 you can have fun checking the sap as it increases in sugar content as it gets closer tot he draw off point.
Regards,
Chris

[Big_Eddy]

Great to see that my original post is helping others to make their own flue pans. You might be interested in the new thread I started that shows making a syrup pan using the same brake with a twist.

[afretired]

Ready to weld the two halves together. Back gassing (purging) helps the inside of the welds.

Sugarmaker thanks for the info, I may need to talk with you in more detail a little later.

Big Eddy keep up the good ideas.

David

[Bernie/MA]

Has anyone used a pressbrake to build a flue pan? What kind of dies are required?

[jimbo752]

Id like to see the new thread, how do i find it?
Thanks
Great to see that my original post is helping others to make their own flue pans. You might be interested in the new thread I started that shows making a syrup pan using the same brake with a twist.

[Sugarmaker]

David,
That sure is starting to look good for the flues. Nice welding work! And I like the custom clamp design to hold the flue and the end plate.
Is the "box" inside allowing gas to be in the joint during welding?
Question? Are you going to design and build a drain into the bottom connecting all the flues and allowing it to exit through the side of the arch?
BTW my old custom Amish built King pans only have 10 flues of about the same size. Still boils pretty good!

Chris

[Sugarmaker]

jimbo,
http://mapletrader.com/community/showthread.php?t=10036
or look under homemade equipment on main page and look for 60 minute pan thread.
Chris

[Bucket Head]

David,

Nice job on the pan. People are not going to beleive you when you say its homemade. Have some in-process photo's in hand when your showing it, lol.

Steve

[afretired]

SugarMaker
I started welding the flues using a piece of aluminum tubing for a form/heat sink and I wasn't real happy with the back side of the welds. So I welded up the ends and drilled a series of small holes in the edge and added a small fitting to pipe argon into. The argon on the back side really cleared up the welds. As far a a drain, I have thought about it, but haven't came up with a easy way to do it. Do you have any ideas/pictures on how they are done on "real" pans?

Bucket Head
It's not a slick as the pictures show. Unless you are like my dad and about blind, they will believe it's home made. BTW you have some real good pictures on your site that will help me a lot. I hadn't ran across a good picture of a float valve, and you had just what I needed. thanks

David

[Bucket Head]

David,

I'm happy to hear my photo's are a help. Thats why we "homemade" guys post them. I found your photo's to be very interesting. Your photo's will help many folks when they attempt a pan. I liked the Vise-Grip flue holding tool- I wish I had that when I did my flues. I cut pieces of wood for spacers and clamped everything together. And yes, the wood was very charred by the end of the project. The wood smoke was worse than the welding smoke!

What gas and what diameter tungsten are you using? There are several "mixes" out there for stainless and every welding supply will recomend a different one. At least thats been my experience when it came to gas on the MIG with the stainless wire. A couple of weeks ago I purchased a TIG unit like yours so I was wondering how it was set up. Thanks.

Steve

[afretired]

Chris
I'm new to the TIG process, though I've had the machine for a few years. When I bought it I was needing a stick machine to weld old farm equipment, and I wanted the capability to TIG. My MIG (Miller 210) works great, but for rusty steel you need a stick machine. I figured when I needed the TIG, I would teach myself. Well that time has come. I'm using 1/16 tungsten and 100% argon gas, and -DC. I've had a hard time over the last few weeks learning how to TIG the thin stainless. As long as I have a heat sink I can get by, but without it, it's tough.

It looks like the stainless you used is thicker than what I used (22g). How did you bend it, and shear/cut it?

Well we have snow and freezing rain this morning, so I guess the sugar house will be put on hold and it's back to the flue pan.

David

[Big_Eddy]

Stainless TIG is 100% argon. MIG uses TriMix and other blends. For the thin stainless (20-24 gauge) a heat sink will help a lot. For a corner weld, get the tightest fitup you can and just fuse the 2 together, no filler. If you need filler for the inevitable hole or two, 0.024" MIG wire is the best option.

Weld a bit hot and move fast to try to avoid letting the heat build up - will reduce warping.

Welding with the joint vertical (downhill) will also help as you are moving away from the heat and chasing your puddle.

Backpurge to prevent sugaring.

Some guys make it an art - I'm not one of them. I did a lot of practice pieces before I started my pan.

[Bucket Head]

Just for comparison, does anyone know how the factory pans are welded? I know they fuse the joints, at least for the most part anyway. I know they back-gas them. What else?

The back-gassing fixture is'nt really absorbing much heat, so the factories are getting away without any heat sink device. If I'm remembering correctly, there is a tungsten that is smaller than the 1/16". Its measured in thousanth's- forty thousanth's stick's in my head but I may be wrong. A smaller tungsten would help out. Once we all figure this out, all the TIG welding Mapletrader's WILL be artists at it!

As for my pans, their 16ga. stainless, MIG welded with .025 wire. Yes, thicker steel than most pans, but they boil! Don't get me wrong, I still had to stitch weld them and be VERY careful, but overall it went well and was not a problem for me. A good friend of mine sheared and bent the pieces to my specs. and I welded everything here. I would'nt hesitate to reccomend that ga. steel and the MIG process to someone that might build a pan and is not comfortable with, or does not have acess to a TIG welder.

Like I said, we'll get this thin stainless TIG stuff figured out.

Steve

[Sugarmaker]

David,
The round copper drain was already soldered on to the bottom of the stainless flues when I got my pans.
Ideas: if you could reach between the flues and weld then you could weld on a small square piece of stainless to the rear end bottom of the flues. then drill a hole through the flue into the tube. This would require welding four spots on eat each point where the tube crossed each flue. Getting this sap tight might be a trick? Need to get someone to take a good picture of the drain attached to the flues on a new factory pan.
How ever you attach it remember to have it very secure to resit the torque from tightening and or loosening the drain extension coming out the side of the arch.

Cutting:
Yes my material for the WRU project was much thicker .030 to .050 thick. I cut the material with a food grade electric skill saw 7-1/4 blade turned around backwards. Also many cut off type blades in a 4-1/2 inch hand grinder. Don't try this at home! This was not cutting, this was very noisy whittling! Lots of burrs to clean up too. It was great fun.
Bending:
I'm cheap! I built a $5 brake in the style of Big Eddy's and went to bending. No its not perfect, neither am I, if I waited for everything to be perfect I would get even less done.

Chris

[Paperman]

Any updates on the completion of the pan? Im really interested on how you finished off the ends of the pan. Not the flue ends but the corner where the flues tie into the front and back "walls" of the pan. Seems it would be a pain to fit right. Great looking. RK

[NYMaple]

I'm curious about the brake... I don't quite understand how the thing hinges. Does anyone have a sketch.

It seems like I could just use a piano hinge beneath the angle piece. Is this right?

I've read all of the descriptions and looked at the photos, but without seeing one work I just can't get it to sink in!

Thanks!

BTW - Great looking project!

[Paperman]

Take a view of my thread. http://mapletrader.com/community/showthread.php?t=10535

In post 5 it shows a few pics of the hinge.

[NYMaple]

Great --- thanks!