Help! Reality Sinks In. Block Evap w/pics

[valleyman]

I insulated the front of the evap. and wanted to do a test boil with the pans. A couple of major problems I hope you can help.

1. I overlapped the lips of the pans and I got a bunch of fine ash in all four pans. I'm thinking I need to place a strip of rail gasket in between the pans and let th eweight of the pans hold it in place.

2. I got a good boil under the 1st and 2nd pans and small boil on 3rd pan and just warmed up water in the pan closet to the stack. The problem is that there's not enough heat reaching the back pans. I built up the inside hoping the flames would be nice and close but the flame isnt getting there enough. I mak have tear lower the inside so I can just stoke a bigger fire so the flame hits more direct like the front pans.

Suggestions are welcome
Thanks
Greg

[Haynes Forest Products]

Can you put angle iron between the pans to help support the pans and allow gasket material to lay on it? Next time you boil get a flat piece of steel and just set it on the top of the flue pipe and see what happens to the boil. It will take a few min to get the results so keep tweeking it.
With the pans hanging down to far into the arch you can create alot of turbulance and that can cause the fire to get off track and suck in the cold air. Keep in mind that there is differant types of heat in your arch. One is direct heat from the flames hitting the pans and the other is radiant heat from the fire. As cool air from the front vents coming in can blow the heat away from the front pans and yet they will get hot due to radiant heat because they are so close to the fire. Keep trying a combination of vents and flue vents. NO amount of testing and tweeking will help if you have a built in problem so start with the seals
Lastly every hole, gap and space that air can enter your arch during firing will allow cold air to enter and create a blanket of cool air between the hot fire and the pans so get the seals right.

[vtmaplemaker]

you could try a forced draft, or a longer stack.. these both will increase the heat created by the fire, and help to pull it towards the rear of the rig...

[Dennis H.]

Splitting your wood finer would also help alittle.

That is the same door that I use on my barrel evap and the size of wood that you are useing looks like twice the size as mine.
You will have to fire more often but it will cause one heck of a fire.
Also try to alternate the wood each time you fire, side to side then front to back. Like a log cabin. This will keep the wood open and let the air to get to the wood better than if it is just tossed in.

I couldn't tell but what are you using for a draft vent on the front? Are you using just the cast draft door? I think in my opinion you will need more draft opening than what that will supply. The stock draft door was ment for a wood stove for your house or garage not an evap.

[RileySugarbush]

You have basically the same set up that I used to use and it ripped along very well. The back pan was often boiling the best, but it takes long to get to that state.

If the fine ash bothers you, add small strips of steel between the pans for each lip to rest on as suggested. You will need to cope out on leg of angle steel so it can sit flat.

I also agree that the wood is far to big. Smaller splits will give a lot hotter fire, and therefore more draft which makes the fire burn yet better. All air in this rig should probably come in below the grates. Close the door and open the vents. Otherwise the draft will pull too much air over the fire and under the pans. If your vents are too small ( looks like they might be)then you need to find another way. Maybe the $20 leaf blower.

What you have there can work very well. Hang in!

[Haynes Forest Products]

Valleyman are the grates between the loading door and the bottom vent door?

[3rdgen.maple]

Sounds like alot of good advice. My thoughts are alot of the same. Smaller wood about the size of your wrist, Criss cross it like lattice, fire more often, open the draft (ash)door instead of using the circular ones to get more air under the fire. If you are getting ash in your pans I think that you are not getting a good draft in your stack. What diameter stack are you using, how much did you restrict the opening in the arch to your stack, and how long is your stack? If you get a good draft in your stack it should suck the ash up and out. So open up that draft door to get a better burn and allow more air into it for the stack to draw it out. I would try the smaller wood and opening that draft door first , if it works great if not then I would make some changes. Remember that back pan will be were you add the raw sap so essentially it is your preheater and will never maintain a boil. So concentrate on the other pans.
Last thing is how full of water did you have the pans?
Just when we think we are golden BAMMMM another delima, I feel the pain just keep at it and it all come together. Good choice on the test boil also.

[Gary R]

I agree with all these guys. smaller wood. I have the same door on mine. I left the ash door wide open all the time. Also, like 3rd gen. said, if your putting cold sap in the back pan, it will be hard to keep a good boil.

Looks nice and this is the time of year to figure this stuff out:)

[red maples]

So from the pictures it looks like its about 4-5 feet with the 4 hotel pans. So your Ideal stack from my experience with the brick rig should be 6" and about 10 feet high. You will get a nice boil becase the pans are nicely nestled in the arch as apposed to being on top so that is a definite plus. the side of the pans won't cool down!!! If you overlap your pans then you will create a small air gap where the pan edges don't meet(if that makes sence) Because the edges of the pans are round and only have the very fine edge of the pan to sit flat. What I did last year was what haynes said. To make a tight seal I made a frame of angle iron and flat stock and riveted themtogether (beacuse I don't have a welder) with stainless rivets and some bolts and put in rail gaskets and it fixed the problem. another thing you can do is find a resaurant suply store and they sell stainless bars that go between the hotel pan in steam tables I don't know if they would hold up to the heat but you can try them. Also the gasket gets pretty gummed up from tranfering the sap from pan to pan but when I was done boiling I Cleaned the pans put the rail gasket in some water and hung it up to dry and that seemed to increase the life of it. the other things you need to think about is the draw off. Have a spatula to wedge under the pan to lift it up. and save a few gallons of sap or some water so that when things get low you don't burn your pans.

[JohnM]

My block arch seems like it always needs a little more air.

I find the best boil is with a blower pointed under the grates.

After loading wood I also crack the top door for a cleaner burn.

[3rdgen.maple]

Have a spatula to wedge under the pan to lift it up. and save a few gallons of sap or some water so that when things get low you don't burn your pans.


Just a thought but go to a hardware store and get some stainless door pulls and drill some holes in the lip of the pans on each side, install them and presto pans with handles.

[valleyman]

Thank you all for the suggestions. I'm going to take the suggestions about the steel frame and rail gasket.

I was already outside downsizing my split wood. I'm halving the splits again.

Haynes Forest,

The grates sits just below the fire door in between the draft door and the fire door.

I'm beginning to think I should of invested in a small evaporator!

[valleyman]

I forgot,
I'm also going to get the stack size taller and try the different draft options.
AM I OK with the duct pipe coming in from the rear? Will that just blow flame straight at the door? OR would I be better off opening the front ash door and push air directilt throughthat openning?

[Cabinet man]

I have a friend that has put a blower from the rear. He gets a lot of ash, smoke and flame in the face. I think that he put a foot switch on the floor so that when he opens the door he can shut it off. Not sure if it is above or below the grates. He is running a 22 x 66 and said it was a big improvement over no blower. I think that it would work fine if you can keep it below the grates. Looks like you are on the right track. Just keep dialing it in and you will have it where you want it.

[C.Wilcox]

Just another thought....how long did you let the fire burn before making your assesment on how well it boiled? I ran nearly the exact same setup this spring and I noticed that it took a long time for the arch to heat up. A long time as in a couple of hours of good roaring hot fire. I think all the masonry sucked heat from the fire, but once the brick got hot it took a much smaller amount of firewood to keep a boil going. Everyone has already said it, but smaller wood was key for me. I actually used only the branches from a dead elm for firewood. Nothing bigger than 4" in diameter. If you had just bought a small evaporator you would have denied yourself all the fun of building and obsessing over the one you have. :)

Just a warning from my personal experience about pan removal...if you pull out one of the pans quickly while the fire is raging along you might get a face full of flame. When you pull the pan the fire is going to reach for the in-rush of oxygen and that means it's coming right at you. That might have been because I didn't have a very tall stack and the draw wasn't what it should have been, but either way, I'd go easy at it the first few times to test how it will react unless you like answering questions at work about why you have no eyebrows.

[valleyman]

3rd Gen,

My stack is 6" diam x 8' tall with a damper in it. The opening from the evap to the stack is roughly 7" square opening.

Do you think I should expand the firebox by taking down another row of block that I have built up from the floor?

Current setup has the fire box about half the length, then there's abut a 16" wall up to the next level. From the higher level the bottoms of the back two pans sit about 2-3" above.

Thanks

[valleyman]

C Wil,
Thanks for face full of fire warning. Me being absent minded and caught up in the moment, I might of baked my face.

I did the boil on Saturday and it rained hard just after I stoked the fire. Less than Two Hours of burn time time because I was a cheapskate and I felt like I was wasting wood. Sounds like I needed to keep it going longer.
Greg

[RileySugarbush]

Valleyman,

If you add your blower it should definitely come in below the grates. It doesn't matter if it is blowing in from the front or back. Mine was from the back so it was quieter and out of the way. I put a firebrick a few inches in front of the blower duct to help direct the flow up through the grates.

For sure put a switch on it!

[danno]

That's about the nicest outside rig I have seen - good job!

Ditto what everybody else said about forced air and higher stack.

Regarding ash, if you can press the gasket between the two pans, you can get by without using a steel strip under that. I would not use the steel strip unless you need it for support.

I would not increase the size of your firebox until you have test fired follwing the advise you have received. In you pic, it shows a couple of logs burning gently. That's a hotdog or marshmellow fire, not a syrup fire. As others have said, smaller wood, fill the box half way up and let it RIP. Forced air and higher stack will help with that.

[valleyman]

Hey. its me again.

I can get a hold of some angled steel used for utility shelving. The kind with all the pre drilled holes for adjustments. Do you guys think it would last if I placed rail gasket over it? Or will it be a pile of warped metal after my first boil?

Can you tell I'm obsessing again. Let me know if there are support groups out there for our type? My wife and kids think it's time for some therapy.

[red maples]

Its not obsessing, Man you've been bitten by the maple bug and have the maple sickness.

some states have a maplehaulics meeting in the summer, I missed the one for NH, this year. I here its like "Quote from KenWP" bunch of guys standing around an evaporator with boiling water in it. Hi my name is Bob I'm a maplehaulic it's been 6 months since I tapped a tree or boiled sap I almost slipped up this morning and filled up the evap. pans with water and filled it kindling before I realized what I was doing.:lol:


good idea to put handles in the top of the syrup pan.

I don't know if those shelving rails would be thick enough because with good maple syrup fire its burning quite hot the door on the front of an evaporator will glow red which takes about 1200 degrees F or more for that to happen.

One other thought about loosing heat from the concrete blocks. Could you line the inside with refactory cement???

[valleyman]

Red maples,
No kidding, I am feeling sick now that you mention it. : )

Actually, I have the sides and back lined with full brick and the floor lined with splits (half brick).

I just got a price on 18' cut to the lengths I need and it would run me about $75 for 3/16 or 1/4" rail OUCH. Little more than I expected. I'm gonna sniff around for some old stuff before I commit. Yeah, I like the handle idea. They will be a huge help.

[C.Wilcox]

Valleyman-

The purpose of the gasket is to prevent the ash you saw in your pans right? Are you certain that the ash is leaking into your pans from underneath or is it possible it's drifting down from the top of your stack? I also overlapped the edges of my pans and had small amounts of ash in my syrup; some of which was from underneath (especially when I burned pieces of softwood) and some was from above. In the end, it didn't change the flavor of the syrup one bit. I tried to keep the big stuff from getting in, but pretty much ignored the small stuff. If you're planning to sell I would continue to fret over it, but if it's for personal use, don't get too caught up. Just filter your syrup, while it's still hot, through a clean T-shirt and it will remove all the bigger particles and leave you with a nice clean product.

Keep in mind that if you use a blower you will get a much hotter fire, but you might increase your ash problems as a lot of it will get forced out of every available crack and up the stack as well. I read a great post on here a while back where a guy advised people to build a fire in their evaporator like they were trying to "destroy it with fire!". So encourage your arsonist tendencies and give it another shot. Find every small stick and piece of kindling you can and feed it in there as fast as it will burn.

[valleyman]

C. Wilcox,

Yeah, that what I'm hoping the gasket will do. The ash was coming up through the small gaps, I could see some flame dying to get out too. The stack was cranking pretty well too but I didn't actually see ash coming from the stack.

I'm not planning on selling it but I do plan on giving it as gifts and bartering for some honey from my beekeeper friend so I want to produce a clear and tasty product. I plan on putting up some kind of temp covering when I start boiling for real.

Smaller wood coming up! Yet another good reason to stay outside and keep me from all the other "real" work that needs to be done around the house. You do know we have are priorities in order right? Just ask all the wives out there.
Thanks for the help.

[Haynes Forest Products]

Remember that a piece of angle iron with hole is not very strong because of the holes. Look around for a bed frame they are good enough for this app. The tighter the seals the better the rig will boil. Dont start excepting small imperfections in the system they will all add up and then when you read about someones rig that is kicking butt you will wonder why.

Its like vacuum leaks in the woods 1-2-3 next thing you know you need 100CFMs to get 10HGs

Remember that your sealing out the ash coming out but also the cool air going in so do it right and do it nice:rolleyes:

[valleyman]

Haynes,
You're doing half my thinking for me. Thanks for the bed frame suggestion. I like your idea about perfection. Even if it's only a block evaporator, I do want it

[3rdgen.maple]

Valleyman I would take the damper out of the stack or leave it wide open. Let it draw some of that ash out the pipe. As far as taking down another row of brick, go for it a bigger firebox means more wood and more wood means more heat right. Pipe diameter sounds good height well not so sure I got 15 feet on my 2x6 and it works very well. Im thinking maybe a mapleholics meeting at your place. Everybody bring some stuff they think will help you out, you provide the boiling soda's and food.:o

[valleyman]

You guys are most welcome to come down to CT. Maybe if my wife sees the conviction in all of you, she wont think I'm such a nut job.

I may go to 10'. I did put a hardware cloth screen up top in the rain cap. Should that cause any ill effect? Maybe the rain cap is starving me of air flow.

greg

[red maples]

see that ask a question and you'll get 10 answers!!! I got my angle iron from the local salvage guy think I paid like $6 for the everything!!! I get lots from him pallets too...if ther're clean and what ever else.

[Dennis H.]

The rain cap may be also where some of your ash problem is coming from.
The 1st year I used a rain cap for about 5 mins! it caused alot of ash to fly back down and into the pan. I got ride of it and problem solved.

The hardware cloth shouldn't cause any ill effects. I am also looking at adding some to my stack to help cut down on some of the sparks flying.

Adding a fan, I think, will make the biggest improvemnt to your boiling rate.
I have mine coming in from the back under the grates.
Word to the wise, duck!! I lost my eye brows a few times!! So I would advise to get down low before you open the door to add wood.

I do agree with the others that it will take some time to bring the whole evap up to temp. The more mass that it made out of the longer it will take, but once it is up to temp it will be able to maintain a more consistant boil.

[3rdgen.maple]

I would recomend keeping the rain cap. I don't want rain in my arch rotting it out. Then again you got block. Test it and take the rain cap off see how it goes. Take that cloth off and see how it goes. I have never had any kind of screen on my stack and do not have problems with sparks coming out the stack that I notice. How much clearance is there from the top of the raincap to the top of the pipe? maybe it is too low on the stack choking it.

[valleyman]

There is about 2-3" clearance that is open. There's more room than that cause of the dome but that's about it. Sounds like I'll keep it on when not in use the, remove it for boiling weather permitting.

The evap is in the backyard and I have some trees that overhang close by so I think I'm going to try to take the cap off and place some screen over the top.

6 bucks. That's great. I'm getting the word out for bedframes and I'll continue to look for scrap.

I told my wife about the meeting and she thinks you're all a little nuts!:lol:

[danno]

[I told my wife about the meeting and she thinks you're all a little nuts!:lol:[/QUOTE]


We resemble that remark:)

[3rdgen.maple]

Nuts? Naw just committed maplholics. 2 to 3 inch clearance is too small raise that rain cap. When I was a younger lad I installed pellet stoves when they first got big and had to get certified to do so. I was told and followed that regulation back then that your raincap had to be as high as the diameter of your pipe in order to get the proper amount of draft. So a 6 inch pipe would need a 6 inch clearance.

[red maples]

maple trees have nuts??? can you eat 'em sell 'em are they sweet like maple candy??? :lol: :lol: just kidding!!!

[swierczt]

I had many of the same problems when I first built my barrel evap w/ a 2' x 3' pan 12 years ago. Could not get a good boil to save my life. Here's what I did to get my little barrel up to 15 gal/hr (on best days).

- Jerry rigged rain cap with a hinge to be wide open 8" pipe when I was boiling, and close when I'm not.

-Added a blower w/ a manifold below the fire and mainfolds above the fire to get the second burn. Kinda looks like an exhaust manifolds on and engine along the top of the evaporator.

-Cut the size of the firebox in half (half the barrel). Raised the back of the firebox to only 1" below the pan to force the gases and smoke right against the pan before going up the stack.

-Insulated the door and 1" rope gasket material between the bottom of the rails and pan. Keeps smoke and soot inside.

-Cut wood down to to bigger in dia. than my wrist, no longer than 12". Keep the wood pile small in the evaporator, the door closed and add wood every 7 min.

This works for me, but I'm sure everyone has there own tricks!

[valleyman]

Swieczt,
Thanks. I like your ideas. I'm going to cut a bunch of the sheet metal away from the raincap to open her up as much as I could, just leaving the supports, Then I'll hinge it like you did.

I'm cutting all my wood down like you and everyone suggested.

I'm going to re design my base stack and I'm going to add rails and gasket.

As far as the gasket, you used rope instead of the ceramic material. Any particular reason?

Your barrel rig sounds pretty hot man. We should get a picture post going with all the homemade jobs.
Greg

[swierczt]

I used a rope gasket b/c that's what they had in the bargain bin at the True Value store at the end of the season a few years ago. I used to use ceramic, but every time I'd take the pan on and off, and when I would tip it to get all the goods out (when the fire was out of course) it would fall apart...I tried the rope and it's held up better than the ceramic. I'll try to get some pictures up one of these days...I had a huge brach fall on my sugar shack and damage the steam vent, roof and stovepipe. Once things are straignted out, I'll post some pics.

[Fred Henderson]

Home type fiberglass insulation can also be used.