Adding steel to a cinder block evaporator [Archive]

Swingpure

07-20-2021, 11:16 AM

This is my first post. I am new to the maple syrup hobby/business and I am looking forward to this Spring when I can tap my first trees. I will start off tapping 16 trees on my property.

I plan to build a cinder block evaporator.. I will be poring a 6” concrete pad for it to sit on and will add sand on top of the pad. The pad is to help prevent any root fires as it will be built partially in a forest.

My side walls will be three and a half cinder blocks long and three cinder blocks high, plus a four inch solid block on top to ensure I have enough clearance from the bottom of my pans and the stove pipe..

I plan to have a 1/4” steel end wall that the stove pipe will come out of (the pipe hole centered about 15” off the ground). I will have cinder blocks behind it to help support it.

I also plan on having a removable 1/4 steel front wall, that has adjustable air intake holes near the bottom of the plate.

The goal is to also have steel to help protect the side walls. I forget the official name, but there are steel strapping that can attach to the side walls, that you can then attach your steel to, that will create an airspace between the steel and the blocks, hopefully helping to protect the cinder blocks. The steel would be 3” off the bottom and from the top to help create convection currents between the steel and the wall.

I will have 1 1/4” heavy duty steel grate sitting on some 3” bricks on the ground, to help with the air flow from the bottom.

Up top I will have four stainless steel 20x13x6” pans, which should encompass the entire length of the evaporator.

Am I looking for trouble using all of this steel, or is it a good thing? Any advice on any of this would be appreciated. I am still in the planning stages, but will be pouring my concrete pad likely next week. I have my pans, pails, lids, spigots already. The trees are already marked, as I have many other species of trees in my forest.

Thank you.

Pdiamond

07-20-2021, 08:02 PM

Welcome to the trader. You say you are tapping 16 trees. how many taps? Make sure your chimney is as high as possible and try to create a slope behind your fire box area. Kind of like a regular evaporator. this will concentrate the fire on the bottom of the pans more. I wish I could draw on this but if you look on the site you will see other evaporators and builds that will give you ideas. Make sure to keep it fun and have plenty of wood. You will burn a lot it not like heating your house. Do not use a damper in the pipe run it straight. Make sure you have plenty of storage for all that sap and really enjoy the end product, it's the best when you make it yourself.

Swingpure

07-20-2021, 10:01 PM

Thanks for the reply.

16 taps for the 16 trees. One tree is greater than 20” in diameter, so technically I could add a second tsp.

I guess I have a lot to learn about the slope. I was going to have wood burning for all 51 inches of pans and then was going to be my stove pipe sticking into the firebox, surrounded with some additional cinder blocks. Should I instead make a slope with sand, a foot or so away from the back wall leading up to the bottom of the stove pipe entrance?

Swingpure

07-20-2021, 10:29 PM

One other question. I have watched many You Tube videos on cinder block evaporators. Some simply stack the blocks and others mortar or cement the blocks together. Is there a real advantage in mortaring/cementing them?

I saw some very expensive high temperatures resistant mortar. Can you use just concrete?

Super Sapper

07-21-2021, 05:46 AM

A 24 inch deep firebox should be enough for that size. You can then slope up to within 1 or 2 inches of the pans or just do a straight wall up. The reason for reducing the area under the pans behind the firebox is to keep the heat against the pans otherwise it will short-circuit under the pans. As far as mortar, I would hold off for the first year as it will be easier to make adjustments and most likely you will have to replace cracked blocks.

Swingpure

07-21-2021, 11:05 AM

I guess where I get confused with the talk of a slope and directing the heat, my plan was to have burning wood virtually totally under all of the pans, with the flames licking the bottom of each pan. My exhaust port for the stove pipe, will come out the end wall and out and up. It sticks into the firebox about five inches. All the rest of the fire box should have burning wood.

aamyotte

07-21-2021, 01:42 PM

What the others have mentioned about the slope is that the rear section under the pans would slope up. The firebox itself is the width of the evaporator x 16" to 20" deep. Then you have a back to end the fire box, this back stops below the pans to force the heat to the bottom of the pans as it makes it's way to the chimney. Hopefully the attached photo works (first time posting a photo). I have a home made evaporator with buffet pans on a barrel. I added brick inside the barrel to create the 'back' of the fire box.

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Pdiamond

07-21-2021, 08:11 PM

good photo

Pdiamond

07-21-2021, 08:16 PM

I would go with some sand maybe. You will get some that crack because of the heat. Have you given any thoughts about any kind of shelter while you boil? You don't want to be out in the rain/snow and try to boil down sap. Just some more food for thought.

Swingpure

07-22-2021, 07:37 AM

I am going to make a temporary, removable shelter, made out of wood frames and a wood half wall and a tarp for a roof. The cold is not an issue because if I was not making syrup, I would be on the ice, ice fishing. It would be good to be able to keep precipitation off of the work area.

berkshires

07-22-2021, 10:25 AM

Welcome Swingpure! I've only been doing this a half a dozen years, and I never built a cinderblock arch. I did build my own arch (out of an old wood-burning stove), so I did learn one or two things the hard way. I'll answer your post point by point.

This is my first post. I am new to the maple syrup hobby/business and I am looking forward to this Spring when I can tap my first trees. I will start off tapping 16 trees on my property.

For your first year, depending on how much time you have to devote to it, that seems like a manageable number of taps. I'll get more into estimating boiling times later.

I plan to build a cinder block evaporator.. I will be poring a 6” concrete pad for it to sit on and will add sand on top of the pad. The pad is to help prevent any root fires as it will be built partially in a forest.

My side walls will be three and a half cinder blocks long and three cinder blocks high, plus a four inch solid block on top to ensure I have enough clearance from the bottom of my pans and the stove pipe.

That sounds reasonable to me so far, but maybe folks who do cinderblock arches can weigh in on how high the sides should be and what they should be made of.

I plan to have a 1/4” steel end wall that the stove pipe will come out of (the pipe hole centered about 15” off the ground). I will have cinder blocks behind it to help support it.
Seems to me you'd have more stability if you had the pipe coming off the top of a cinderblock, rather than out the back of an end-wall.

I also plan on having a removable 1/4 steel front wall, that has adjustable air intake holes near the bottom of the plate.

I wouldn't bother with adjustable air holes. You want a big opening that's open all the time. You need to have the same area of opening coming in as you have going out. So if you have a six inch stovepipe, that's 29 square inches. You need the same space for air in the front. If the arch is 20" wide, you will need at least 1 1/2 inches open along the whole width. Any less than that and you're starving the fire. Some folks add a blower to further increase the amount of air going to the fire, but you can get into that later if you decide to do that.

The goal is to also have steel to help protect the side walls. I forget the official name, but there are steel strapping that can attach to the side walls, that you can then attach your steel to, that will create an airspace between the steel and the blocks, hopefully helping to protect the cinder blocks. The steel would be 3” off the bottom and from the top to help create convection currents between the steel and the wall.

Your cinderblocks can tolerate the heat much better than steel. You do not want steel strapping in the fire, particularly if it's structural in any way. It will warp and fall apart. Anything in your arch made of metal (with the exception of the grate) needs to have the inside surface protected with insulation, and the outside surface exposed to air to help it cool. If it's in the middle of the arch, unprotected, with no air on the outside, it's going to get chewed up in no time. And the only reason why the grate can take it (sometimes - some people go through grates pretty quickly) is because it has cold outside air flowing up through it.

I will have 1 1/4” heavy duty steel grate sitting on some 3” bricks on the ground, to help with the air flow from the bottom.

Sounds good. Make sure your front "door" is set up so that all the air coming in is directed under the grate. Then have something that closes off the airflow on the far side of the grate, so the air can only take one path - up through your wood. Otherwise cold air will take the path of least resistance and go around the wood. That will cool down the inside of the arch and allow the fire to be starved for air. And as others said, the firebox - the part where the fire is (and the grate) should only be like 18 - 20 inches deep. So you only want wood from the front door, going back about 20 inches.

Up top I will have four stainless steel 20x13x6” pans, which should encompass the entire length of the evaporator.

Once you get this optimized, you should get on the order of one gallon per hour boiled off per square foot. So you've got about seven square feet. A good week mid-season may get you five or more gallons per tap. So that's eleven hours of boiling time. If you have that kind of time to put into boiling, you should be fine.

Am I looking for trouble using all of this steel, or is it a good thing? Any advice on any of this would be appreciated. I am still in the planning stages, but will be pouring my concrete pad likely next week. I have my pans, pails, lids, spigots already. The trees are already marked, as I have many other species of trees in my forest.

Thank you.

Yeah, all that steel is a mistake. :) Can you say more about what you're trying to accomplish with it? I'm sure we can help you figure out how to do what you're trying to do without the steel in the arch.

Also, figure out the inside of your firebox before you go any further. If you look around on here you can find examples other folks have given on how to make a "ramp" in your arch. If it were me I'd probably just add cinderblocks behind the grate, and fill in gaps with vermiculite or insulation or something. You're aiming for probably 1 1/2 inches between the bottom of the arch and the pans.

Have fun!

Gabe

Swingpure

07-22-2021, 06:13 PM

Thanks Berkshire for the detailed reply. I wish I read it earlier as I just bought $50 of steel for the walls and floor and I was so proud of my design. I was worried that having never read about steel in the firebox, that it was a bad idea. The whole point adding the steel, was to protect the cinder blocks.

Looking at the concrete block evaporators on line, it always looked like they had a fire the length of the concrete and open flames touching the bottom of each of the pans. Only having burning logs for the first 20” or so is a radical change of thought for me.

I will have to totally rethink the whole design, including moving the chimney to the top.. I still may be able to use the steel to help with the slope. I will also have to change the concrete pad it will sit on, as it will have to be deeper.

Thanks for the response.

Pdiamond

07-22-2021, 07:49 PM

Depending on how much steel you purchased. You may be able to use it in the future towards the building of an arch and then get yourself really setup with a good stainless steel pan. Of course by then you'll be thinking to yourself, hmmm, now how can I grow my operation just a little bit bigger.
By the way I will tell you that this becomes an addiction, an itch to grow, etc., etc,. Always though keep it fun and share with others.

Swingpure

07-22-2021, 10:15 PM

22395

I totally redesigned what I was going to build. This crude drawing is what is between the two side walls. The back wall will now be concrete blocks and there are blocks inside to aid the slope. I will include a steel plate that will go from the grate up to the top of one of the blocks to act as a slope. I will have another steel plate that will go from the last pan to the end of the concrete wall and the stove pipe will come out of that.

The front wall will still be a metal plate, that I will lift to the height of the grate to allow air in. I will play with the exact height when the times comes.

It will be interesting to see if I get addicted to making syrup and how many taps I will have in year two, but we are still at least 7 months away from year one, but I will be ready for it..

Super Sapper

07-23-2021, 05:30 AM

For one it is not too late to get out before the addiction hits. After my first year with 12 taps cooked over a fire pit I was going to make a block arch. That turned into why not make a steel one as I had the rest of the year to get it done. First I figured a 2 X 4 would work but why not a 2 X 6 as long as I am building one. That went from going to do 40 taps to 126 taps. From there is went up to 425 a few years later and then I concentrated on being more efficient and am at about 400 now. This site is a great resource and you will learn a lot.

Looking at your drawing it looks like you have the pans dropped into the evaporator. I would only have the bottoms come in contact with the heat and flames. By setting them in deeper you will scorch the sides of the pan above the sap level.

Swingpure

07-23-2021, 07:04 AM

Looking at your drawing it looks like you have the pans dropped into the evaporator. I would only have the bottoms come in contact with the heat and flames. By setting them in deeper you will scorch the sides of the pan above the sap level.

Virtually every cinder block evaporator I have seen on line has the lip of the pans on the edge of cinder blocks, and the pans sunken down below the top of the cinder blocks, including the gentleman I bought my pans from. My impression it helps to seal the heat in.

As I build it, I may raise tbe last pan or two a couple of inches as they will only be 1.5” above the heat flow.22396

aamyotte

07-23-2021, 11:01 AM

I think the pan can be recessed to keep the sides warm however there should be something at the base of the pans to stop the fire from running up the sides of the pan. This can be achieved by using 8" wide block for the arch and 6" block for the top course. This allows the pans to sit on the 8" block and block the flames. The 6" block would need to be cut on the height if you are using 6" tall steam pans.

Swingpure

07-23-2021, 02:31 PM

In the attached pictures from on line, this person just offset the top row a half inch or so, to try and keep the flames off the ends of the pan.

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I also see how he used some blocks instead of any metal plates to act as a ramp with an initial flat wall.

Wannabe

07-23-2021, 06:18 PM

Yeah keep the pans dropped down in. It will boil a LOT better. You'll get some scorching on the sides but it doesn't affect the taste like you think it would.

Swingpure

07-24-2021, 06:20 PM

Wannabe

07-24-2021, 06:41 PM

Sometimes I wonder if I overthink the design of the evaporator. This video with this high energy, cheerful woman certainly simplifies things and makes the process seem even more wholesome.

http://YouTu.be/uCts2DqzkJo

Yep, you can throw a lot of money at this 'hobby' if you want. Or you can keep it simple and have fun (and spend a lot more time boiling).

berkshires

07-27-2021, 11:06 AM

berkshires

07-27-2021, 11:31 AM

I'm just curious, have you looked at all the other threads here on building a block arch? There's a ton of good info that covers a lot of these issues. Here's a start: http://mapletrader.com/community/search.php?searchid=7998589

Cheers,

Gabe

Swingpure

07-27-2021, 08:54 PM

I have read a ton of threads. Unfortunately your link did not work. To be honest sometimes it is confusing as there seems to be many ways to skin the cinder block evaporator cat. I have made many changes since I first posted this.

I have poured my concrete pad to protect the roots and will cover that with several inches of sand. I am going to wait to talk to some experts at CDL when they reopen in August. I pretty well have my final design in my head, but just want to talk to them to do it the best I can. I know adding firebricks would make it better and last longer, but that adds hundreds of dollars more for the brick and proper mortar.

berkshires

07-28-2021, 12:43 PM

Sorry the link didn't work, but it sounds like you've already poked around a bit. I think this arch is not too dissimilar to what you have in mind, and he's been boiling on it for 20 years, so it can't be all bad LOL

http://mapletrader.com/community/showthread.php?12045-How-to-Building-a-block-arch.

If it were me, I'd do something like that ^^^

GO

berkshires

07-28-2021, 12:47 PM

I pretty well have my final design in my head, but just want to talk to them to do it the best I can. I know adding firebricks would make it better and last longer, but that adds hundreds of dollars more for the brick and proper mortar.

I agree you probably don't need firebrick to get going. What did you think of my suggested modifications?
http://mapletrader.com/community/attachment.php?attachmentid=22403&d=1627401964

GO

Swingpure

07-28-2021, 10:39 PM

The metal plate and stove pipe in your link is almost exactly like I will be doing. Interesting about the solid blocks. I just got my remaining cinder blocks this morning and will go with them this year. I just went out and took some pics using the flash. I still have to cut the front plate to fit as a door.

Today besides getting the cinder blocks, I built a frame to hold 3.5” of sand over top of my concrete pad and will have sand outside the frame as well. Once that is in place, I will start placing the cinder blocks in place on the sand, over the pan. I still have to cut my grate to fit. I also cut a metal sheet in half and will have it on the sides. I still think it will help protect the cinder blocks, but if it fails, I will simply remove them, at the first sign of failure. I will also add concrete to fill in the gaps at the ramp, so it is solid and helps with the airflow under the rear pans.

I am going to up my tree count for tapping from 16 to 20. That should get me into enough trouble for my first go at the maple syrup making addiction.
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aamyotte

07-29-2021, 07:21 AM

I would recommend making a test boil with water to iron out any kinks once you have it built. It will give you the time to make modifications as necessary.

Super Sapper

07-29-2021, 10:47 AM

You may want to add a little obstruction just before the stack to divert the heat to the outside so it does not short-circuit up the middle.

Swingpure

07-29-2021, 08:57 PM

I would recommend making a test boil with water to iron out any kinks once you have it built. It will give you the time to make modifications as necessary.

Thank you I will give that a try as soon as I get my stovepipe plate made!

Swingpure

07-29-2021, 08:58 PM

You may want to add a little obstruction just before the stack to divert the heat to the outside so it does not short-circuit up the middle.

Thanks, I would not have thought about that, I will do that.

Swingpure

07-30-2021, 09:45 PM

Today I hauled with my ATV and bush buggy trailer the sand, from a local pit, that I put on top of the concrete pad. I placed 3.5” of sand on top of the pad. I then placed the concrete blocks in their proper place. Tomorrow I have to cut to length the metal sides, the floor grate and the door, with my angle grinder. I have to find the right side block to slow the airflow to the stack. I am relying on a neighbour to cut a hole in a plate and add a collar for the top plate for the stove pipe, then I can do a trial boil.

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SeanD

07-31-2021, 07:32 AM

I'm enjoying reading about your progress. I wish I had been doing so much prep in the summer. I always seemed to decide (and often still do) on better ways to do things in January!

What's the purpose of the sand? If you have a level, frost-free surface like a concrete pad to work on, use it. One of the benefits to getting into a sugar house for me was getting off of the ground. Earth wicks moisture no matter how much you try to protect it and it adds ice cold moisture to your firebox. The pad also makes shoveling ash out easier. Maybe consider using that sand as an additional fire barrier around the pad and build and burn right off of the concrete.

Sean

Swingpure

07-31-2021, 12:38 PM

What's the purpose of the sand? If you have a level, frost-free surface like a concrete pad to work on, use it. One of the benefits to getting into a sugar house for me was getting off of the ground.

I was worried the heat from the fire would hurt the concrete. The sand is to help protect the concrete. The sand is firm and contained. The whole area will be protected from any snow.

Today I added the metal sides. I can remove them easily if I find that they are a negative. My hope is that help retain more heat and protect the cinder blocks somewhat. I also cut and placed the grill to fit. It sits on some smaller concrete blocks. I also cut the metal front door and added two wood handles to make it easy and safe to move.

I have a little more sand to add in the “slope” area and I am now at the mercy of a neighbour to cut a hole in a metal plate and add a collar for the stove pipe. The distance from the front of the evaporator to the inside of the back wall is 5 feet. Does that mean that my stovepipe should be 10 feet tall?

In September I will make the bones of a temporary sugar shack.

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aamyotte

07-31-2021, 08:58 PM

If you have enough sand you should fill the block cavities with sand. It will help hold the heat in the firebox.
Once you test fire, you might want to try raising the grate closer to the pans to see how it increases the boil rate.

Z/MAN

07-31-2021, 10:36 PM

I think you are going to have to lift your grate up a few inches. If not it will plug up with ashes and coals and the draft will not be able to come up from below your fire.

Swingpure

07-31-2021, 11:08 PM

I think you are going to have to lift your grate up a few inches. If not it will plug up with ashes and coals and the draft will not be able to come up from below your fire.

Thanks, I will put another layer of blocks below it.

Swingpure

07-31-2021, 11:45 PM

A few questions about stove pipe for my evaporator.

Is regular galvanized stove pipe (good to 1000°) okay to use?

I can make the hole in my metal plate for the stove pipe, 6” or 8”. Are both good? Is one better?

Can I use a 45° angle in the stove pipe run, or does it have to be dead straight?

Thank you.

Swingpure

08-02-2021, 05:55 PM

I am glad I am building this well before the tapping season, as you learn from your mistakes. In hindsight, I should have seen this one coming.

Normally when people do their cinder block evaporators, they just find a flat piece of ground and build it on it, often just before sap season. In my case I really did not have a unused place to build it on, other than off the edge of a parking area in the bush. Hence, I did the extra step of making a concrete pad for it to sit on, to protect the roots of the trees. Then I did another extra step of adding 3.5 inches of sand on top of the concrete pad, contained with a wood frame. All was good when I placed all of the cinder blocks on the sand.

Then it rained. The rain water had no where to go with the concrete pad below it and the wood sides bordering it. The sand all turned into a sloppy mess and the cinder blocks started to get off kilter. Seems like an obvious result now.

I have removed all of the blocks and have removed all of the sand. I am going to let the area dry and I will rebuild it with some changes.

The cinder blocks will sit directly on the concrete. In the fire box area, I will lay a piece of metal over the concrete. I will then lay a layer of fire bricks on top of the metal and will mortar it in place. Then will come my four inches of bricks to raise the grate off the firebrick floor.

On line if you look at 98% of the cinder block evaporators, they are uncovered. I would like to cover mine, with a gazebo like structure, with half walls. The sole goal is to keep precipitation off the pans and me while I am working there and perhaps have a place to sit in a sheltered corner.

To help facilitate the stove pipe going outside the roof of the structure, I will have the opening of the stove pipe at the end of the evaporator, instead of on top. Seeing a tip on another old post, I will make a concrete form 18”x20”x7.5” with the 6” stove pipe sitting inside. The bottom of the pipe will be 8” from the bottom of the block and 6” from either side of the block. I will add steel to the form to give the block some additional strength.

Swingpure

08-03-2021, 08:42 PM

I rebuilt the cinder block evaporator directly onto the concrete pad. I cut some metal for the floor of the firebox and I placed fire brick on top of the metal. I have to cut some pieces of the fire brick tomorrow to make for a tight fit. I added some 15x15 concrete patio stones to fill in the open area of the edges of the “slope”.

I poured the concrete block with the stove pipe placed 8” above the bottom of the block. The block will be very heavy as it took 3 bags of concrete to fill the form, but it will sit perfectly at the rear of the evaporator.

Because the stove pipe exits out the back of the evaporator, it allows me to add a hot plate at the rear to have a fifth pan to preheat the sap. By the weekend I may be ready for a test burn, boiling some water in the pans.
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Pdiamond

08-04-2021, 06:24 PM

That's looking pretty good. Let us know how the boil goes.

Swingpure

08-05-2021, 04:02 PM

No pictures today, but I drilled and bolted on angle iron on the firebox bottom metal plate in order to hold the firebrick snugly on it.. Also cut to fit, the firebrick for the firebox area.

The metal bottom plate and the firebricks are not in place yet, as in the next day or two the +180 lb vent block needs to be moved into position and it will be a beast to move. I may get help from a friend with a tractor.

On a side note, I went to CDL near Barrie for the first time, that is a Maple Syrup meca for the area. I picked up my pails, lids, spigots, filters, a hydrotherm and a cup for it. I also ordered a refractometer from Amazon today.

Pdiamond

08-05-2021, 06:38 PM

Please get help with that big block. Do Not hurt your back. more hands are better in this situation. Trust me

Super Sapper

08-06-2021, 05:02 AM

If you are putting a metal plate on the bottom it will warp quite a bit unless anchored or enough ash to insulate it. I would go without it as it will not provide much if any insulation for the concrete.

SeanD

08-06-2021, 07:55 AM

Ditto on the metal plate on the concrete. The concrete pad will handle the job better than you think. When I worked up my operation in stages, my last year on a block arch was on the concrete floor of my partially finished sugar house. Even with my evaporator now, the ash and coals drop onto the same spot with not issues. If you really want to play it safe, but still give yourself flexibility to modify, lay some half or full fire bricks flat on the concrete pad. That will do more than a metal plate and you have the benefit of repurposing the fire bricks to brick the evaporator you are eventually going to get. Based on the level of maple addiction I read into your posts, I give you two years tops.

Swingpure

08-06-2021, 06:36 PM

Thanks for the tips on the metal plate.

I have firebrick already cut to fit, that will go on top of the metal plate and hopefully will insulate it. There is angle iron on the metal plate that holds the firebricks in place.

If the metal plates on the sides or bottom, give me any trouble at all, I will remove them.

I might wait a couple more weeks before doing a fire test. I want the special vent block to be more cured before exposing it to heat. I will likely try and get I to position on Sunday, if I can get my friends tractor here.

Swingpure

08-07-2021, 01:18 PM

Today I got the heavy vent block in place by dragging it in boards, partially with the use of the winch of my ATV and partially by pulling on it with straps. It fit perfect. Once that was in place I was able to cut to fit the hot plate. It was just meant to be a filler between the pans and the vent block, but I think it can work to preheat some of the sap. I have no idea of how hot it will get, but I will move the handles of the pots away from any intense heat.

The pictures do not show the firebrick or bottom grill that go above the bottom metal plate. (Beats me why the pictures sometimes show up sideways, I purposefully held the camera vertical to prevent that.)
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berkshires

08-07-2021, 01:57 PM

Looks good! Just as well you got rid of the sand. Not sure how you would have cleaned out ashes without cleaning out sand at the same time.

I would try to find a small steam pan and cut a hole in your metal plate if you want a warning pan. Or if you really just want to use pots then cut holes in the steel plates so the pots can sit over the holes.

GO

Swingpure

08-07-2021, 07:03 PM

I would try to find a small steam pan and cut a hole in your metal plate if you want a warning pan. Or if you really just want to use pots then cut holes in the steel plates so the pots can sit over the holes.
GO

Thanks. My plan is to try and get another steam pan, the pots are the back up. I will likely try it without making holes, then if that does not work well, I will add the holes.

I am going to do a test boil with water, but I have decided to wait three more weeks to do it, to give the newly poured vent block a greater chance to cure and get moisture out of the concrete.

I fitted all of my firebricks and added the spacers and grill. I felt like I was all dressed up for a party and no where to go. I almost can’t wait for Spring now. I have many of the accessories I will need, just a few more things to get.

I also have to build my shelter (a poor man’s sugar shack), but that is a nice to have.

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Pdiamond

08-08-2021, 06:43 PM

You have done a really fine job of building that block evaporator. I wish you nothing but the best.

Swingpure

08-19-2021, 02:53 PM

I have made my final changes, adding angle iron to the metal side plates, to just slightly raise the steam pans so that I can grab them easier and I added 4” wide flat steel bars between the steam pans, so that the flames do not go up the sides.

Depending on when the expected thunderstorms hit Saturday, I hope to do a water boil test of the evaporator. I just have to further split some dry popular and I have pine wood scraps from a housing addition, that I will burn in the test. I will also put on 6’ of the eventual 12’ of stove pipe for the test. It is so hot here with the humidex, I am almost half way there to the boil.

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Swingpure

08-21-2021, 05:19 PM

I had my test boil today. It was both a real success and a failure, but that are what tests are for.

The fire started right away and immediately smoke was coming out of the stovepipe. I did not have to add a lot of wood before the fire was roaring. Within 8 minutes one of the pans was starting to boil and under 10 minutes two of them were at a good full boil. The rear hot plate got warm and worked well.

The failure was the metal steel sides. I know I was warned about them. Now they did protect the cinder blocks and I think they helped with the heat retention, but they did slightly warp and they pushed out the top forward cinder blocks, almost causing the one steam pan to fall into the fire. They are now permanently out, but I will have to reinvent a way of keeping the lip of the steam pans up enough to grab them.

It was hot out during the test. With the humidex it was 40° C (104° F). I am sure it will different out during the sap season.

I will do one more test boil without the metal sides, but with whatever I come up with to keep the pans up an inch or so.

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Wannabe

08-22-2021, 08:36 PM

Have you thought about trying to attach handles to the top lip of your pans so you don't have to try to 'prop' them up?

Z/MAN

08-22-2021, 11:04 PM

You can use firebrick to both protect your block and sit your pans on them. You will learn that super hot fire you will have, will do many bad things to steel after a few/ many hours of boiling sap.

Swingpure

08-23-2021, 05:36 PM

Have you thought about trying to attach handles to the top lip of your pans so you don't have to try to 'prop' them up?

I thought about that and if what I did today does not work, that will be plan C!

Swingpure

08-23-2021, 05:56 PM

Today I made some changes to allow the lip of the steam pan to stay above the concrete blocks. I added wider 2” stones on the third course that stick slightly into the fire box area. The pans can sit on the ledge created. I added two courses of other two inch stones for the ends of the pans and will likely add a third, once I go back into town again to get them.

I have the steel plates under the pans to help prevent the flames from going up the long side of the pans, but they add no real structural value. I will remove them, if there is any negatives with them.

I will likely do another boil test on Friday when the temperatures are supposed to be lower for a day.

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Swingpure

08-23-2021, 06:09 PM

You can use firebrick to both protect your block and sit your pans on them. You will learn that super hot fire you will have, will do many bad things to steel after a few/ many hours of boiling sap.

I have fire brick on the bottom, but if I put it on the sides, my understanding is I would have to concrete in the cinder blocks so that they do not move. Also the cost of the special mortar that can withstand the heat is super expensive.

I am not sure when you concrete together the concrete blocks, how easily it would be to replace one of the blocks if they break.

Z/MAN

08-23-2021, 10:05 PM

I have fire brick on the bottom, but if I put it on the sides, my understanding is I would have to concrete in the cinder blocks so that they do not move. Also the cost of the special mortar that can withstand the heat is super expensive.

I am not sure when you concrete together the concrete blocks, how easily it would be to replace one of the blocks if they break.

I have a home made 2x3 arch that I lined with firebrick when I built it about 12 years ago. I stacked the 1/2 firebrick splits with no mortar and they are still stacked all these years later.

Swingpure

08-23-2021, 10:09 PM

I have a home made 2x3 arch that I lined with firebrick when I built it about 12 years ago. I stacked the 1/2 firebrick splits with no mortar and they are still stacked all these years later.

So you simply stacked them against the wall and they stayed stacked while adding wood?

If so, I will get more firebrick.

Is the bottom of the sidewall firebricks on top of the floor firebricks, or do they touch the floor, with the floor firebricks against them? (The floor firebricks sort of holding the bottom of the wall firebricks in, if that makes any sense?)

Swingpure

08-24-2021, 08:06 AM

I have a home made 2x3 arch that I lined with firebrick when I built it about 12 years ago. I stacked the 1/2 firebrick splits with no mortar and they are still stacked all these years later.

I went outside and checked and it turns out that two firebricks, one vertical and one horizontal, fits tightly under my extended brick and has the added benefit of mostly protecting the underside of the extended brick. The weight of the extended brick holds the firebricks tight.

By adding the firebrick, I would have to reduce the width of my grate by 2.5” and by extension, the firebox itself would lose 2.5” of area. I am not sure how big of a factor that is.

On the bonus side, it should really help to protect the cinder blocks and perhaps make for a hotter fire.

It would take 21 blocks to do the side, and another 6, to protect the flat face of the slope.

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aamyotte

08-24-2021, 08:36 AM

One thing I have read on the forum is that people with block arch fill the block cavities with sand to help make the block last longer and it also helps retain the heat.

Swingpure

08-24-2021, 09:31 AM

One thing I have read on the forum is that people with block arch fill the block cavities with sand to help make the block last longer and it also helps retain the heat.

Thanks. I was was worried the sand would get wet from precipitation and when it froze, that it would expand and crack the blocks. I know sand should drain any water, but I sure have seen some pretty wet sand.

aamyotte

08-24-2021, 10:59 AM

Thanks. I was was worried the sand would get wet from precipitation and when it froze, that it would expand and crack the blocks. I know sand should drain any water, but I sure have seen some pretty wet sand.
that's true our climate can do nasty stuff to concrete. If you put a tarp over it when not in use it would keep the arch relatively dry and also keep the snow out if you don't have your shelter over it all winter.

Swingpure

08-24-2021, 06:16 PM

I added fire brick to the side walls of the firebox and just have to trim the end pieces. I also added a third course of pavers up top.

The pans fit snugly, the lips are easy to grab, and no flames can really come up any of the sides. I am happy with the design.

Once the fire brick is trimmed, it will be good to go for another test.

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Z/MAN

08-24-2021, 10:05 PM

That looks great! I would now add a couple more firebrick for the grate to set on. Adding these against the wall will make it a lot easier to clean out the ashes.

Swingpure

08-25-2021, 05:42 AM

That looks great! I would now add a couple more firebrick for the grate to set on. Adding these against the wall will make it a lot easier to clean out the ashes.

Thanks. The floor of the fire box is currently all fire brick. The only area not firebricked, is the front face of the “slope”. There is sand in the two leading cinder blocks of the slope. I could add firebrick for the bottom 9” of the “slope” face.

Swingpure

08-26-2021, 08:06 PM

I had my second boil test and I will give it a C grade. The fire started right away, smoke started coming out the stovepipe right away, but flames started coming out between the door and the the steam pan. It was partially self inflicted as I did not have the steam pan tight to the edge, but there is still a gap there. I will have to come up with a better door.

The first two pans came to a brisk boil pretty quickly. The third pan barely got a boil and the fourth pan never boiled and was just steaming. I gave them boiling grades in the attached picture. I have to figure that so much heat was coming out the front, that it was not flowing to the rear and out the stovepipe, as much as it should have.

Also another self inflicted mistake was after I had removed the pans, I could see I had no ashes whatsoever in the last six inches of the firebox. I did not push the wood far enough back. That certainly would have helped with the third pan.

In both tests, the 2nd pan in from the front boiled first, the 1st pan was right behind it and the third pan was quite a bit later before it sort of boiled and the fourth was the slowest. Even if I improve the flow to the rear. The first two pans will boil the most, followed by 3 and 4. Assuming that I get 4 to boil, would you, put the fresh sap into pan 1, then 4, 3 and then 2 to make the nearup?

Now to design a door. I have it all in my head. Hopefully sealing off the front, will force the flow of hot air to the rear and boil the fourth pan.

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Swingpure

08-26-2021, 09:20 PM

In the first picture I took off the web, the person only had one row of blocks as the “slope”. Mine has four rows of blocks as the “slope”. If I reduced it down to three, or down to two rows, I would have a lot more fire directly under the pans.

Is that a bad thing, to reduce down to 3 or 2 rows?

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Super Sapper

08-27-2021, 05:16 AM

18 to 20 inches deep should be good for the firebox. As far as your boil, it seems that you need more chimney pipe to increase your draft. Fire out the door, low boil in back pans and no ash in the back of the firebox all point to insufficient draft.

aamyotte

08-27-2021, 05:37 AM

I have seen a thread on here somewhere which said that chimney height needs to be double the length of the total pan length for good draft.

Swingpure

08-27-2021, 07:24 AM

Thank you both. I do have 9’ more pipe ready to put on, but was saving that for when I built my removable “sugar shed” in the spring and attach the tall part to the top of the structure, but I guess I need to add more pipe now for the tests.

I will not change the length of my “slope” until I do another test with a longer stove pipe and an improved front door. I am going to start on the door later today.

aamyotte

08-27-2021, 09:17 AM

berkshires

08-27-2021, 09:52 AM

Others said exactly what I was going to say: You have insufficient draft. Two things about that:

1 - The more draft you have, the hotter your fire. Think coals in a firepit on one side of the spectrum and a blast furnace on the other side. One can melt iron, and the other can barely toast a marshmallow, LOL. The main difference between the two is how much air is going to the coals.

2 - In addition to the amount of heat generated, the amount of draft will also regulate where that heat goes. Too much draft and your stovepipe will glow cherry red, because you have so much heat getting pulled all the way back out the stovepipe. Too little and, as you see, you'll get no boil in your back pan(s).

Regarding the door: Whatever else you do, I'd suggest buying a chunk of fire blanket and strapping/bolting it to your door. It's kind of fluffy, so it'll help you get a good seal against your front pan, it'll keep the heat from being lost through the door, and it'll keep you from singeing yourself every time you get close to the door. It's not too expensive, and it's amazing stuff. Here's a link to the 1": https://www.amazon.com/Insulation-Morgan-Ceramics-CM-Ceramics-Instructions/dp/B015GD0QCW. They also sell 2" if you want it.

Cheers,

Gabe

Super Sapper

08-27-2021, 11:01 AM

The other part of the draft that I forgot to mention is to have enough opening under your fire to let air in. It should be close to equal in area to your stack diameter. Chocking off your incoming air will decrease your draft also.

Swingpure

08-27-2021, 12:08 PM

If you look at the commercially made units, they have a small firebox at the front and a long ramp. As you say best to test with the chimney first. It's much cooler to test now too.
Another note, are you using seasoned hardwood for the test as well? The wood can have an impact on the amount of heat you are generating changing the results.

Thanks. Yes I am using seasoned wood for the test.

I will try6 additional feet of stove pipe, a better front door, placement of fire wood all the way to the back and the front tray all of the way to the front. It would be great to see the rear tray boiling.

SeanD

08-27-2021, 03:23 PM

Those are all good improvements - except moving the fire all the way to the back. Keep the fire up front and see if you can get the draft to pull the heat back. It's normal for the pans right above the fire to be the hottest and boil first and for the back pans to take the longest to come to a boil. Tweaking your setup to get the back pan boiling from a fire up front is the goal. There are a bunch of backyard sugaring threads on the MT about that. I remember some of my own.

Your air going in appears ok. A 6" stack has an area of 28" or so and it looks like you have that under your door. As others have said, lengthen your stack. With a good draft, you won't need a super tight door. If you have flames reaching for cracks in your door or coming toward you when you open it to fire, you need more draw from the back. Fire wants air.

One factor you won't see with a test boil is that your cold sap will be getting added to your pan furthest back - so that pan will always be working harder to boil than the others. Don't sweat that. I think some people fail to take that into account when calculating boil rate for their steam pan set up. Subtract around 2 gph (one pan's worth) from your total to get a more realistic number. In theory, 4 pans should give you 8+ gph at its peak, but in reality, it will be closer to 6+ gph.

The other thing you won't get from a test boil, but will work in your favor in a longer boil is the build up of coals and overall heat in the firebox. If you get plenty of air going in, your fire should rage and need to be fed every 6 minutes or so. At the 6 minute mark, the wood currently burning is still going, but it's mostly used up. It's light and almost like charcoal, but it's still going. I push that backward and the new wood goes in its place. The original wood finishes itself off in the next minute or so and provides the back pans some extra heat as the new wood gets going.

Okay, one last pro tip that will also help shorten your day. The whole firebox stays crazy hot for hours when you are done for the day. That's just lost heat if you don't use it, so plan ahead to "flood" your pans at the end of the night. Take off your finished syrup then fill your pans up all the way with raw sap. While you go inside to finish off your batch, that raw sap will boil for a little while then simmer then just steam for a couple hours. Go back every so often to make sure the levels don't get too low. Eventually you'll get a feel of how close an eye you need to keep on it before you can leave it. You'll knock out a few extra gallons that way.

Swingpure

08-27-2021, 05:17 PM

Okay, one last pro tip that will also help shorten your day. The whole firebox stays crazy hot for hours when you are done for the day. That's just lost heat if you don't use it, so plan ahead to "flood" your pans at the end of the night. Take off your finished syrup then fill your pans up all the way with raw sap. While you go inside to finish off your batch, that raw sap will boil for a little while then simmer then just steam for a couple hours. Go back every so often to make sure the levels don't get too low. Eventually you'll get a feel of how close an eye you need to keep on it before you can leave it. You'll knock out a few extra gallons that way.

Great advice, thank you. The last one I had not heard before and would not have thought of.

My test boils have been relatively short, with basically only one load of wood in it, so as you mentioned I have not taken advantage of the long term heat. I will push the coals to the back.

I will make a better door.the thin metal one I was using was already starting to warp.

SeanD

08-27-2021, 06:48 PM

The warping is hard to avoid, but the insulation Gabe/Berkshires shared goes a very long way to keeping it under control. It's amazing what that 1" of insulation can do. Unprotected, it will get dinged by the wood a bit, but you'll get through one season for sure.

Swingpure

08-27-2021, 08:12 PM

Regarding the door: Whatever else you do, I'd suggest buying a chunk of fire blanket and strapping/bolting it to your door. It's kind of fluffy, so it'll help you get a good seal against your front pan, it'll keep the heat from being lost through the door, and it'll keep you from singeing yourself every time you get close to the door. It's not too expensive, and it's amazing stuff. Here's a link to the 1": https://www.amazon.com/Insulation-Morgan-Ceramics-CM-Ceramics-Instructions/dp/B015GD0QCW. They also sell 2" if you want it.

Cheers,

Gabe

So the blanket is on the fire side of the door?

Thanks

Swingpure

08-27-2021, 09:19 PM

My friend also suggested that with it being hot and humid out, that it would affect the draft as well. He said it would have worked better in cooler weather. Cooler weather is on the way.

I have added 6 more feet to the stove pipe. It is about 108” tall now, double the 51” steam pan length. I have another 3’ pipe I can add.

The fire blanket in Amazon is not available at the moment in Canada. I am not sure quite how to attach it to the concrete door I am planning to use. I purchased a 24”x36” patio stone, that I am going to cut into pieces to make the door and surrounding frame.

I likely will have another boil test in a few days when we get cooler weather.

Swingpure

08-28-2021, 01:37 PM

So I added 6’ more of stove pipe. Cut from a 24”x36” patio stone, an end piece for the forward edge of the evaporator, so that pan#1 could sit tight against and minimize the heat that could escape that way. From the same stone, I cut another piece for the door and it sits firm and pretty snugly. Perhaps in the future I will attach a fire blanket to it.

I took the advice of pushing the coals back. ( more on that later).

A big change in pan #3 (third from the front). It actually boiled vigorously first, followed by pan 2, then 1. #1 was a little slower, because when I pushed the coals back and put in new wood, I left really nothing for it to get the new wood raging, so lesson learned.

#4 never did come to a vigorous boil. It got lots of bubbles and almost boiled, but never quite did. It confused me a little with #3 boiling so hard.

I guess I still have a draft problem. Not sure if the fact it was hot and humid again and the wind was blowing back to front, was the difference or it it something else. The door is sitting on cinder blocks, that have it about 1/2” above the grill. I am not sure if that has a negative effect. Lots of smoke was streaming out the chimney. It definitely did not get red hot. I did not use a fan today, like the other day. Eventually I will make a decent blower for the spring.

The two preheat pots got plenty hot and had some small bubbles, but did not boil, but I did not expect them to.

The three steam pans will certainly boil a lot of sap, I just have to figure out #4. I know if I removed one of the four rows of the cinder block slope and made the fire box deeper, that would solve it, but there is likely a smarter solution.

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Swingpure

08-28-2021, 02:36 PM

One thing that might help pan#4, that I noticed when I took off the pan. I had metal plates at the long edges of the pans to keep flames from going up the edges of the pans. With “4 being totally above the slope, there are no flames to worry about. Just a little thing, but it would drop it a 1/4” and the heat would fully, directly go on the whole pan and not some to the metal plate. I figured the pan got to within a degree or two of boiling, that could be some of the difference.

I also did a lot of goggling on warmer weather affecting draft and the consensus is hat it can have a big impact, so I am not going to worry about it until the next test late October before the snow flies..

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berkshires

08-28-2021, 05:59 PM

So the blanket is on the fire side of the door?

Thanks

Yup. After your fire has been burning a while I would think that paver you're using for a door is going to be a hot boulder to have to move every few six or seven minutes. I'd go with steel with insulation.

Gabe

aamyotte

08-28-2021, 09:06 PM

My friend also suggested that with it being hot and humid out, that it would affect the draft as well. He said it would have worked better in cooler weather. Cooler weather is on the way.

I have added 6 more feet to the stove pipe. It is about 108” tall now, double the 51” steam pan length. I have another 3’ pipe I can add.

The fire blanket in Amazon is not available at the moment in Canada. I am not sure quite how to attach it to
I attached my fire blanket to the steel by welding roofing nails with the head to the steel. Then I was able to push the insulation through the nails to impale it and keep the insulation in place. Then I added 2" x 2" plates with a hole in it over the nail snug to the insulation and tack welded the plate.

Swingpure

08-29-2021, 07:22 PM

Okay, one last pro tip that will also help shorten your day. The whole firebox stays crazy hot for hours when you are done for the day. That's just lost heat if you don't use it, so plan ahead to "flood" your pans at the end of the night. Take off your finished syrup then fill your pans up all the way with raw sap. While you go inside to finish off your batch, that raw sap will boil for a little while then simmer then just steam for a couple hours. Go back every so often to make sure the levels don't get too low. Eventually you'll get a feel of how close an eye you need to keep on it before you can leave it. You'll knock out a few extra gallons that way.

I can see this can give you a head’s up on the next day’s boiling, if you have not boiled all of the sap that day. I had been thinking as I was getting closer to shutting down, that I would empty a pan into another once and replace the sap with water. If you have boiled all of your sap, you would do this, but if you have not boiled all of your sap, this would be a big advantage for the next day.

You could be finishing that day’s sap, while still boiling off some water for the next day’s sap.

Once again, thanks for the tip!

Swingpure

10-15-2021, 10:48 AM

It was mentioned to me that the 2” thick concrete block I am using as a door, would be quite hot to move as the evaporator got hotter. I added two handles that I originally had on my steel door. I actually tried mounting the steel door onto the concrete block, which I was able to do, but it was too heavy. The concrete door, I just have to slide to the side, so with the handles, it makes it much easier to do. The concrete door sits pretty air tight on the top and sides.

I added the fifth pan, as a preheat pan. It was four inches deep, versus the six inches deep of the other pans. I had raised the level that the fifth pan sat on by two inches, so I had hoped it would sit level with the other pans, and it fit perfectly.

Monday morning the temperatures are supposed to be 5° C (41° F), which should be representative of temperatures, when I boil in the spring. I will be doing one last boil test Monday morning to see how the draft works at that temperature, and will see how pans 4 and 5 boil. In the summer when I tested it, when it was really hot, and the draft not in peak conditions, pan 4 almost boiled, but did not. My big hope in this test is that pan 4 boils. Pan 5 is a preheat pan and if it comes close to boiling, or boils, that would be a major improvement in my overall efficiency. If I can ever get to boiling 8 gallons per hour or higher, that will help me get through the volumes of sap I may get.

Thanks to everyone for their advice to me. It’s ironic at the start I had a lot of steel in the evaporator, steel interior sides, steel back and front and a steel floor. Now the only steel I have in it, is on the floor of the firebox, which has firebrick on top of it.

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Swingpure

10-22-2021, 07:10 PM

Reading the title of the thread, it almost should say removing steel from a cinder block evaporator.

Today a parcel arrived from CDL it was a ceramic blanket strip, 1” thick, 2” wide and 25’ long. I got it mostly for the concrete door to have a better seal. On the fourth boil test there was smoke coming out around the door edges. It is one way I can make the evaporator a little better. I will have to find the best way to glue/attach the strip to the concrete.

I have way more ceramic blanket strip than I need, so I am going to try and MacGyver something, so I can use the strip to help seal off the pan area as well.

Swingpure

10-25-2021, 05:51 PM

Today I glued the ceramic blanket strips onto the concrete door and also cut the lengths to go along the steam pans. If the rain every stops, I will see how they fit maybe tomorrow or Wednesday. With my top greater level being in four layers, I just have to slide back the top layer, the strip will sit on the second layer and after putting down the pans, I will push the top layer of stones in, which will hold the ceramic blanket strips in place.

I will not know how well the doors and the pan strips work until next spring, when the regular season starts, but they can only help. Between them and adding a stone baffle under the fifth pan, I hope to have the fifth pan boiling as well.

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Swingpure

10-27-2021, 12:29 PM

I tried out my idea of sliding the top row of bricks away and then adding the ceramic blanket strips between the bricks and the pans, then I pushed the bricks back in. It looks like it should work very well, sealing off that area.

I also checked on how the material would seal in the door area, and that also looked good, but time will tell how well it stands up.

I placed the concrete baffle in, to help heat up the fifth pan a little better. We will see how well that idea works in the spring. I think that is it for modifications until the spring. It has come a long ways from the first version to the fourth, after four test boils.

I will also have my induction range, in my phone booth like shed to protect it, to increase my efficiency. It is a dual range, on one side I will have my finishing pot, boiling sap, like the pans, and on the other side, I will have a preheat pot, that will add boiling sap to the evaporator and to the finishing pot. The plan is at one point in the boiling process, I will start to take syrup from the pan with the thickest sap on the evaporator, and start putting it into the finishing pot, essentially making the finishing pot a sixth pan. I would continue to migrate boiled sap from pan to pan.

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berkshires

10-27-2021, 01:05 PM

looks good, good luck!

GO

Pdiamond

10-27-2021, 07:29 PM

You've done a very nice job with the arch. are you covering it with a tarp over the winter?

Swingpure

11-05-2021, 06:12 AM

If I replaced the top, front, flat faced cinder block of the “ramp” with a solid concrete, wedged shape block, that would be on a 45° angle and fire bricked it, would the improved slope of the ramp make a big difference to the efficiency of my block arch?

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Pdiamond

11-05-2021, 06:15 PM

Most all manufactured evaporators are made this way. I am not sure at what angle it is. As they say, couldn't hurt.

Swingpure

11-05-2021, 10:16 PM

Most all manufactured evaporators are made this way. I am not sure at what angle it is. As they say, couldn't hurt.

Hmmm, your comment made me think.

I already made the form to pour the angled block, one block deep, at a 45° angle. As you say, it cannot hurt. The angled ramp is mostly under pan#3. Pans 4 and 5 have about 2” space underneath them.

When you said most manufactured evaporators are made this way, it made me think, if I am making this concrete ramp, I could make it two blocks long, versus one block long.

Many angled ramps I look at in pictures are at a 45° angle, some are shallower, almost all are deeper, than 7.5 “ mine would be. If I made mine two blocks long and a shallower angle, the ramp would end under pan 4.

I have no real evidence to make a decision one way or another, but I will go with the single block angled ramp. It will be easy to change back after the first boil.

I will also make a form for a two block ramp as well, as not to waste the concrete from the bag and it gives me three options. If the first boil goes well with the one block angle ramp, I will then try the two block angled ramp and go with what is best for the fourth boil.

Edit: Looking at other evaporators and the long shallow areas they have, I think the one block angled ramp is the way to go. I also calculated the weight of the two different ramps and the one block angled ramp is about 38 lbs and the two block ramp is around 150 lbs, which is a weight not easily placed and removed. I will still make both, just because I will have more than enough concrete mix from one bag to pour both, but will likely stay with the one block ramp.

Second edit: I totally underestimated the amount of concrete I needed, I should have purchased two bags. After I filled the one block form, it was obvious that there was not enough to fill up the two block form. The two block form likely will need at least a full bag, if not a bag and a third. Not sure if I will fill this form, unless I have a need to do other concrete work.

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Swingpure

11-08-2021, 02:57 PM

Colour me happy. The angled concrete block I made, fits perfectly and looks good. I have to put it back in the garage to cure more. (temps outside too cold for the curing chemical reaction). I will firebrick the flat bottom block and the angled block and the sides of the evaporator in the angled area, after I put the angled block back.

Just about the whole third pan will be under the new angled ramp.

I had been told before not to have the flames go up the sides of the pans. I have metal plates at the start of pan1 and between pans 1 and 2, 2 and 3 and used to have one between pans 3 and 4, but found that at that time, there were no flames going up between the pans and it was preventing pan 4 from boiling, so I removed it.

The angled block ends exactly where pans 3 and 4 meet. I think I will put the metal plate back. I can always remove it easily if I find pan 4 does not vigorously boil. I think with the new angled ramp and the baffle I added, pan 5 will also boil.

I have pictures, but had trouble loading any of them.

Swingpure

11-09-2021, 09:15 AM

I have had trouble loading photos the last couple of days, I am not sure if these links will work to show pictures of the new concrete ramp or not. I will firebrick it in a couple of days.

https://photos.app.goo.gl/XYqzFrbTddpEsWiS6

https://photos.app.goo.gl/rBzmbCW45Vq3jDiHA

https://photos.app.goo.gl/9HfLS4TVkm28RD966

berkshires

11-09-2021, 10:47 AM

Your links work great (and the pics are much clearer than the typical uploads). And the evaporator really looks good.

GO

Pdiamond

11-09-2021, 06:50 PM

Very nicely done Gary. I believe you are well on your way to making yourself into a syrup maker. Just imagine that with a raised flue pan in the back and the syrup pan with a draw off valve in the front someday. Inside a nice sugar house with a head tank and incoming float boxes controlling the levels of sap. Yeah I can see it all now. You have done a fine job with the block arch. You should be able to cook off an easy 8 to 10 gallons an hour just keep that fire hot and burning good.

Swingpure

11-09-2021, 08:45 PM

Forgive my rookie question. Is a flue pan a pre heat pan, or the main boiling pan that dumps into a pan to finish the syrup?

I would love if my evaporator can boil 8 to 10 gallons an hour. I tried to build the best one I could. I’m watched a lot of You Tube videos, got a ton of tips and advice on this forum, and I think I did a few things that I thought of. Obviously the original plan to line the walls with steel was a complete failure, but after 4 practice boils. I think I have something good to go into the season.

I can’t tell you how much I am looking forward to the start of the season. I will learn a ton and at the end of the season will decide if I want to expand, do less or just the same. If I want to do the same or more, the big thing will be to reduce boil time, either with larger, better pans or an RO unit.

Swingpure

11-10-2021, 08:17 AM

I am likely going to firebrick the angled ramp area today. My plan is to angle the top of the fire brick to be even with the top of the rest of the ramp that runs to the stove pipe. The area of the opening under the pans 1.75” x16” (28 sq in) almost exactly matches the area of the 6” stove pipe.

I could have the firebrick go up above the flat ramp area, the thickness of a firebrick, (1.25”) and have firebrick extend on top of the block ramp, at least the distance of pan 4. That would reduce the space between the pan and firebrick to a half inch. That would leave an area of only 8 sq inches for the gasses to get through. Although that might make pan 4 super hot, I think it would kill the draft.

My plan is to leave the opening at the 28 sq inches, unless someone tells me I would be just fine reducing it down to 8 sq inches, somehow creating a super jet flow. The narrow area, would open up to a 28 sq in area, prior to reaching the stovepipe.

berkshires

11-10-2021, 10:37 AM

Forgive my rookie question. Is a flue pan a pre heat pan, or the main boiling pan that dumps into a pan to finish the syrup?

A flue pan is the main pan. What makes it different from a flat pan is that it has "flues" - deep fins that extend into the hot gasses in the arch. Effectively it triples (or more?) the surface area of the pan, with corresponding increase in gallons boiled per hour. They are also complicated to make, and use a lot more stainless, and are therefore quite expensive.

I would love if my evaporator can boil 8 to 10 gallons an hour. I tried to build the best one I could. I’m watched a lot of You Tube videos, got a ton of tips and advice on this forum, and I think I did a few things that I thought of. Obviously the original plan to line the walls with steel was a complete failure, but after 4 practice boils. I think I have something good to go into the season.

I agree that 8 gallons an hour is a reasonable expectation. Maybe more if you eliminate the rest of the steel in your arch ;) Seriously - I do think each pan that has the steel covering the long bottom edges is going to lose 10-20% or more of the GPH you'd get from it. One thing you could do if you want to keep the fire from coming up the sides, but allow full fire on the bottom, is to move the steel up between the pans instead of under it.

So right now you're doing 1. I'd suggest doing 2. You could prop the steel up on the sides with a bit of insulation or a bit of firebrick, and then line the top with insulation to keep smoke from coming through the cracks. I don't think you'd even really need to bend the edges of the steel, I just did that for fun. The insulation stuffed in above it will do the trick to keep most of the smoke/gas from escaping.

https://lh3.googleusercontent.com/pw/AM-JKLXMEX8Ig-9q1tAwr8yYjRFIzwjKwR0H91N3yeuu6DAsSFUJjUM1dmwRN-rqVxKkNlPi5mee5KqXlO6xeiAeJPOYgTw_Xk6Po0mqHQjBEYMY nRUV3gflmjIsUOjKlzQimIBX1NBkzEyu6bXF-a7WU-K5=w927-h587-no?authuser=0

I can’t tell you how much I am looking forward to the start of the season. I will learn a ton and at the end of the season will decide if I want to expand, do less or just the same. If I want to do the same or more, the big thing will be to reduce boil time, either with larger, better pans or an RO unit.

If you want to reduce boil time, see above ^^^ ;)

Cheers,

GO