Concrete block arch

[3fires]

Before registering I found this link through Google that a member here posted of how they built their cinder block arch. IIRC, I believe that's how I found this site, by looking for inexpensive ways to make an arch/ evaporator.

http://matthewgroves.com/Hobbies/Sugaring09.html#2

Given my limited space, temporary construction, cost, and local fire codes this, or something very similar, is the way I'm planning to go at least for now.

The block layout is going to be almost identical to the one in the link above, except I'll be using 3 14"x22"x4" SS pans. Also, due to fire code I must keep the fire itself off the ground a minimum of 8". So, I plan on sandwiching a 32"x48"x1/4" thick steel plate which I picked up at the junkyard between the first and second layer of blocks.

This is what the fire inspector accepted, the above linked arch with the addition of a front cover to hide the flames and an elevated steel plate fire platform as described above. I plan on building it directly on the ground in the back yard.

But, I have a few questions about this setup. Don't you just love these newbie questions? :confused:

1. How big should the firebox be? The way I'm planning it mine will be about an 18-20" cube and then I was planning to use dirt, sand or the like to ramp up the flame toward the back where the stack is.

2 and 3. Do I have to line it with firebrick? and if so, does it have to line the entire inside or just the firebox?

4 and 5. Given the planned raised fire sitting on the steel plate do I need to cut slits or holes in the plate to act as a grate? Would it benefit me to do so?

I don't have a torch and think drilling a bunch of holes thru this plate would be a challenge with a power hand drill. But, I could possibly get someone to cut slits in it with a torch, possibly!

I have other questions, but the layout of the firebox, ramp/ arch, and grate are my biggest obstacles at the moment. If anyone has suggestions for obtaining functional block or firebrick on the cheap I'd appreciate that too as it looks like this will be my biggest expense.

Thanks!

[Bucket Head]

Codes requires you to keep the fire off the ground? I've never heard of that.

You would'nt have to cut slots in the plate or line the arch with firebricks, it depends on how fancy you want to get and what your going to cover the fire with at the front. Fire bricks might help prolong the life of the blocks since they don't like the high heat, but its not a "must do". If whatever your going to cover the front/fire with is very tight fitting, you might have to cut slots for draft air. You might want to put one of the blocks under the plate to support it also. I don't think the "ramp" of dirt would be needed. I have used, and have seen, many block arches that did'nt have anything like that and they worked fine. Maybe some others will offer what they did with their block arches, but if you just copied the one in the photo, with the 8" rise, it should work fine.

Steve

[Tweegs]

Still a bit of a rookie myself, but I boiled the last 2 seasons on a block arch.

The firebrick isn’t absolutely necessary, I never used it. The blocks will only last one season without them though. They’ll get brittle and crack, but at a buck a block vs. two bucks or so each for fire brick….

I was using a 2X6 divided syrup pan. Nice that sap went in on one side and you could draw syrup off on the other, but I did have a multitude of problems.

Smoke coming up between the pan and cinder block was a big one, always getting in your eyes. I solved that with high temp gasket material, the cheap fiberglass stuff available from the sugaring supply houses.

You lose a lot of heat out the front of the arch without a door. I used a door from one of those barrel kits mounted to a piece of sheet steel. The steel was screwed to the cinder block via anchors. This worked great until the lead anchors melted…doh!...The steel fell, flames shot up the side of my pan and melted many of the solder joints on the pan. Down a couple of days getting the pan soldered (silver) back up. C-clamps held it place after that. Not pretty, but it worked.

I used dirt to build the ramp inside the arch and to fill the holes in the blocks. Get your dirt before the ground freezes solid…trust me on this.

I would also be tempted to go a little higher on the stack. Better draft for one, two, soot and ash may come back into your pans if the wind is right.

Block arches work, but they can be fickle beasts. Test yours out by boiling water while you can, tweak it as needed. Trying to make modifications in the midst of the season is a real buzz killer.

[3fires]

Thanks Bucket head and Tweegs.

Code says no burning inside city limits period, but the fire inspector said they would allow it if the fire was enclosed and elevated off the ground. I suggested the above plan using cinder blocks or grate to loosely cover the front and they accepted. Codes where I live are quite numerous and very strict, and "neighbors" WILL complain.

I can increase the stack by two or more blocks if needed. I planned on buying a few extra for last minute adjustments or things that may come up. Also, I planned on placing a piece of metal screen from an old HWT in between two of the stack blocks to hopefully catch some ash and embers and keep them from leaving in the first place. I'm not sure how well it will work to catch them though.

But, back to the firebox. If I line the firebox only with firebrick will it prevent the block from cracking? I don't want to build it and have it crumble apart in the first season. I'm looking at 60 to 75.00 with tax for block without delivery and if paying 40-60 bucks to buy firebricks will save the rest of it I'd rather do that.

I figured ramping it up with dirt toward the stack, besides increasing efficiency, would insulate the rear most blocks, would it? or do I need to line those too with firebrick. I was of the understanding that the ramp would both insulate the block and push the flame up toward the pans in the rear.

If I line it with firebrick will it still crack and crumble?

Will the firebricks crumble?

Too late for thawed dirt, it's been froze solid since the first of December. I hadn't even considered that.

How much is the high temp gasket material Tweegs? and how much did you need?

I don't have the door entirely figured out, but I guess I plan on just closing off the front with cinder blocks and pavers leaving 2" on each side or stacking to leave the bottom open, or just lean a steel grate over the opening. I'm open on this one, but can't afford to buy a door kit.

I want it to be as efficient as possible without having it fall apart or paying an arm and leg. Also, I don't want to pay an arm and leg and have it fall apart either.

Would regular red bricks hold up to heat?

I thought the cinder block arches lasted longer, but now I'm not so sure?

I can get a barrel for 5-10 bucks and a someone here posted the stove kit for about 60 bucks shipped IIRC, but I don't have access to a welder and would have to pay someone to config it for the pans, buy a stack, etc. etc.

But, if the cost of the cinder block arch exceeds the barrel stove, or if the cinder block arch only lasts one season I'd rather get the barrel stove, pay someone to weld it up right to fit my pans and be done with it.

I really appreciate all the help.

[whalems]

tractor supply has barrel stove kits for $49.00.

[Bucket Head]

Barrel rigs are nice, and that would'nt be a bad way to go (no codes issues), but you have to line the barrel with fire bricks to protect the thin steel that the barrel is made of. You should also have some sort of grate in it to keep the fire up off the bottom. You would solve a lot of problems with the barrel. No cement blocks, no ruined blocks, no dirt needed, good pan fitment with a competant welder..., no exposed fire, almost all of your heat will be heating sap instead of keeping the ground and cement blocks warm and you can affix however much stovepipe you need for good draft.

Firebricks can and will crack (maybe a few, not all of them) but they won't be rubble like the cement will be. Many, many cement blocks expired in my backyard over the years, lol.

Steve

[3fires]

Are there plans here for a simple barrel stove evaporator? I'd like to use the 14x22 ss pans that I already bought.

I'm not giving up on the cinder blocks, but would like to somehow weigh the differences between the two. And, if i had plans or pics I could have something to show the guy who will be doing the welding. As right now he has no idea what I'm talking about. LOL! "evaporator, arch, what's that?"... "you can't leave the top open it must be sealed or it won't vent properly."

He thinks i'm crazy and I'm starting to wonder that myself.

[Dave Y]

3fires,To convert a barrel stove in to an arch for boiling sap all you need to do is get a 55 gal drum and a barrel stove kit. install the kit and line it with fire brick, I would use the splits as they wont take up as much room. The ony thing you need to do before you install the brick is cut out a space to set your pans down in. once you have assembled all your pieces this could be built in a day and last for years. good luck.

[Tweegs]

I just noticed you were from Michigan, whereabouts?

If you are anywhere near Mason, Sugarbush Supplies can save you on the shipping. The Haigh’s have a supply house out in Bellevue, if that is closer, otherwise the one time sponsors of this site, The Maple Guys,(shameless plug) or Bascom’s will carry it. It looks to be anywhere from $5-$18 a roll, depending on how much you’re going to need.

A word of caution, if you make the trek in to one of these places, take someone responsible with you, one that has not been bitten by the maple bug. Kids, candy stores, and all that. Next thing you know you’ll be looking at tube, T’s, evaporators…it’s what happened to me, honest. :lol:

[Bucket Head]

Your still wondering if your "crazy"? Let me clear that up- yes you are. So are all the rest of us on here! And is'nt it fun trying to explain syrup making and its equipment to people who have no idea? Persistance pays off, both with making the syrup and telling others about it, lol.

Steve

[3fires]

BucketHead, what really confuses the issue is being someone who has no idea trying to explain it to someone who has no idea.

Tweegs, I'm in Oakland county, sw corner. I think I will make a trek out there and see, mainly to ask questions and hopefuly clear a few things up by seeing the equipment. Seeing the euipment online only tells so much, I think I need to see it first hand so I'm not asking questions that are unneccesary and cluttering up the forum.

This is only my second year and I don't want to get in too deep just yet or bite off more than I can chew. I thought this would be a fun, easy and inexpensive hobby. It is fun! But, I'm not so sure about easy or inexpensive. It's hard not to get drawn right in.

I found a guy selling block for .50 cents a piece so if I can arrange transport to haul them I might go that route. The barrel stove does sound much easier though. Teeter totter! LOL!

I don't want to stray off from the cinder block in this thread, but does anyone know the thickness of the barrel stove steel, or better yet which type and thickness of steel would be ideal for constructing an arch from scratch?

In hindsight, I probably should have titled this thread "I have no idea what I'm doing, Help me decide on an arch to build".

[maple flats]

A conventional wood fired arch is only about 20 ga galvanized, about the same as the plenum on your forced air furnace. Then it gets bricked to hold the heat where you need it. Any steel that will hold shape is good enough. The conventional arch has angle iron at the edges, (corners) and the sheet metal fills the spaces. But, fire brick can become expensive in a hurry. I think unless you have a source for used fire brick you will be better off buying new blocks each season until you go to a more permanent evaporator set up. Red bricks will not take the heat and fire brick are around $2.00 each and that only covers about 4.5 x 9", or is it 4.25 x 9?. As for the fire bricks breaking, I have only seen it happen in the firebox when the bricks were laid loose. If the are cemented in with refractory cement (more high expense) I have had none break. I think bricking should be reserved for an official archy, whether bought or home made. But, don't give up, whatever way you go you will make syrup. Keep costs down until you grow more.

[3fires]

Thanks Maple Flats,

If I do use the cinder/ concrete blocks without firebrick will they explode or come crashing down spilling hot sap everywhere?

If I can get these blocks @ 50 cents a piece I'm not woried about them breaking as long as I can continue evaporating.

My biggest concern now is that the arch or stack would fail and blocks and hot sap would go tumbling everywhere.

I'm surprised that 20 ga. galv. is all that's used as I can get a sheet of that for failry cheap, less than the cost of the bricks I believe and angle iron wouldn't cost much more. But, like you said the bricks might be a killer on my limited budget. This might be a project for next year after this season's over.

I've been sitting around drawing up all kinds of different plans and the construction or design of the arch is almost as fun as making syrup. :cool:

[Maplebrook]

3 Fires,
I have read this thread with interest...I used a concrete block arch for 3 seasons with no problems. The block were filled with sand and the arch was lined with firebrick. Some block did crack but they don't explode. The one I built had a steel box tube frame that the pans sat on. The block were laid up around it and I borrowed the lumber strapping tool from the local building supply to strap the whole thing together. Used this rig until I moved up to the D&G.

[SeanD]

I used a block arch for five years. 2011 will be my first season on a "real" evaporator. Many of the blocks from season number one were still in use last year, however I did line it with split firebrick. They are not going to crumble during a boil, so don't worry about that. I have had a few fall apart in my hands, but that was only after the season when I took down the arch. They will become brittle, but as long as they are not getting moved around, they'll be fine. I think I lost maybe 3-4 blocks at the most each year, so you're only looking at $2 loss.


Sean

[valleyman]

Hi 3fires. Here's a link to some photos of my block evaporator. I love it! I'm small time 30-35 taps and it gets the job done well.


http://s778.photobucket.com/home/Valleyman_bucket

[3fires]

Well the family and neighbors aren't too keen on having a big cinder block arch out in the backyard, so, I might not be able to go that route after all. Getting the block here is going to be a pain. I no longer have a truck and will have to pay someone to haul them which is going to double the cost.

Once the family realized how many blocks I was getting a big red light went on in their head. I'm getting much resistance. :cry: My family and neighbors don't seem to share my "passion" for Maple.

So, I'm thinking I'll look into some galvanized and some angle iron. They seem much more keen on that for some reason, mainly because it will be easier to move I guess.??

I think I'll start another thread because I need design tips on that arch and don't want to clutter this one up.

I do appreciate all the help though.

[Bucket Head]

"My family and neighbors do not share my passion for maple".

Well then I guess its time for family and friends to go. You don't need them. How about sending them somewhere? Carnival Cruise Lines has some "specials" going on.

Steve

[3fires]

That's what I'm thinking. How much are used humans going for anyway? Maybe i could sell them and then have enough to just by a nice 2x6 drop flue forced air whambajamba and call it good. LOL!

But, I ain't happy if they ain't happy. It wil just take more thinking now is all....and maybe a little more $$.

[Tweegs]

Well, if it’s any consolation…
The family and neighbors will only care what it looks like this year. Give the neighbors a bottle of the good stuff, your family will be hooked anyway.

Come next year, the smell of maple steam mixed with a whiff of wood smoke will drive them all crazy. By the end of the second year, they’ll all be offering up maples to tap and probably pitch in on building a bona-fide sugar shack. :lol::D

[Sugarmaker]

Good thread! I LOVE IT!:)
A portable arch is not a bad idea and could be quickly removed from view when the season is over. I have a friend that made his own barrel arch and hides it behind his shed in the summer. When he does pull it out most of the neighbors are there drinkin boiling sodas with him and stoking the fire.
Dont give up!
Syrup makers RULE!
Chris

[Bemis]

I tear down my block arch each year at the end of the season. Everything gets stored in the garage until the start of next season. Takes me a few hours to get things moved out and rebuilt. Keep the neighbors in the sweet stuff, and all should be well.

[3fires]

Thanks for the encouragement.

[tylerj]

My block evaporator is actually in my 10x10 glass greenhouse (removable upper gable ends for ventilation). When I'm done the blocks get moved around to become rows for supporting the shelving in the greenhouse. Just set up for my 2nd year with the arch.

[70 Buick]

I just love reading these threads
so many great innovative ideas

[Groves]

I'm just catching up on this thread.

I'm the Matthew Groves whose block arch is linked to in the original post. I hope it's helped some people.

This will be our 3rd year boiling on that same arch, and sure some blocks are cracked (we didn't line it with firebrick$), but every year I say I'm going to tear it down and rebuild...and then I don't. Instead, we just keep building it longer and longer. Might as well boil more sap more quickly, right?

The main thing keeping me from rebuilding is my lack of flat foundation. My current plan (after this season, ha!) is to pour some very shallow footings that will let the blocks at least start out nice and level.

Other improvements will have to be some sort of elevated sap tank to ease filling, and by golly a better filtering system.

I just keep my eyes open for cheap blocks, knowing I'll use them in the future.

You really will need to figure out how your fire will get air. I'm not sure what your inspector will say (or if he'll even see your setup again), but "enclosed" is a pretty variable word. I like it.

Keep us posted on what you do. Let me know if you need other pictures of our arch.

[3fires]

Thanks Groves, those pics are spot on and show the setup very well IMO. I just can't convince the family to allow it. :( The inspector was all for it.

But, I'm working out the details on a fuel oil tank evap in another thread.

[Groves]

To solve the "up all year" dilemma, we just try to use it other times of year as well. We have taken to putting up all our corn using it. Sure beats steaming up the kitchen.

http://gallery.me.com/mcgroves#100347&bgcolor=black&view=grid

[DIMariner]

I'm trying to boil my own sap for the first time this year. I decided that, given my relative lack of skill and money, I would use the Groves-designed block evaporator that has been featured prominently in this thread. I threw it together Friday and did a test boil today. I still need to play around a little to get it performing the way I would like, but I can tell that it will do the job for a novice like me.

Thanks for the design, I'll post a picture once we are actually boiling.

[TapME]

check out the pics in the photobucket 4 my little block arch. There may be some ideas there 4 you.

[Groves]

We added enough blocks to make it hold 8 pans this year. We also added 2 5inch heating flue sections to make the stack effectively taller.

It's not been a good sap year. We've had 3 boil days, and only made 4 gallons total so far.

[3fires]

8 pans! :o That must be a sight to see.

[firetech]

Nicely done !!! you have already figured out that you need the fire closer to the pans. Like you said more brick and move the ramp up to 2in from the bottom of the back pans and get the fire from going around the side and you may double your bioling rate. Sounds like the fire trucks were close.

[3fires]

LOL! as soon as I fired it up the sirens went off.:o I'm surprised it boiled what it did. If I can get all three pans raging I think it will do 10+ an hour.

I put 12 taps in today and the smaller sugars and reds downhill were flowing like crazy. I should be boiling for real by Friday or sooner.

[JPD]

I found that filling the cores with sand and lining the inside with high strength block bond the stuff with the fiberglass in it will help to keep the blocks from cracking, make sure though that the sand is completely dry. the steam will crack the blocks. The sand acts as an insulator too. My 29" x 40" pan would boil off 35 gallons of water overnight just letting the coals die out and everything cool.

[Dan]

Hey guys, thought I would put up some pics and video of my block arch from last year. Maybe someone could use it for ideas. Not much 4 pans, elevated grate, and a too short 4 block stack but worked good last year. Made 4 gallons on 20 taps.
Dan

http://www.youtube.com/watch?v=LcgVJ1nXHyI

[ckkrotz]

We put together a block arch last weekend and boiled down on it. It worked pretty well... We only had 13 gallons of sap, and it took us about 2 hours to get it down to about 1 gallon... but the one problem we had was the smoke was coming up out of the holes in the blocks. It didn't seem to flavor the syrup too bad, but it was sort of annoying. Does anyone know if this is normal or have any suggestions to alleviate it? I don't have any pictures right now, but it is big enough for 2 steam pans, which sit recessed in it, and has an 8 inch stove pipe.

[sap seeker]

Simply fill the holes with sand / gravel, will also help to keep blocks from cracking.

[RileySugarbush]

Make a heat shield for your block!

Go to Home Depot and buy knock down rectangular ducts:

3102

Dimension B is 3 and A is 10 or 12 inches.

Cut off the crimp seam on the short leg with tin snips and hang these by the short lip on top of the block. Let your pan hold them in place. If your want more height you can hang on in the joint under the top course of block.

These help seal up the firebox an really helps your block last longer.

You can hang one on the front of the arch too, to keep air from racing in over your fire. Use another slid in front ( handled with gloves or pliers) as a firing door/draft regulator. Hold it in place with a chuck of last years block.


Another use:

if you are batch cooking and want to lift off your pan and there are still lots of nasty hot coals, you can quickly shut off the radiant heat by tossing some of these over the coals. The boil will stop immediately.

These at the duct tape of block arches.....Cheap and effective.

[DIMariner]

Finally boiled yesterday. It was the first run for my block arch. The arch worked great- ran through 88 gallons of sap in 15 hours, which is nearly 6 g/h. Had I used better firewood, I could have gotten it closer to 7 or 8.

Thanks for the design idea Groves.

Edit: Some pictures (https://picasaweb.google.com/106273007708701612048/BlockEvaporator?authkey=Gv1sRgCLj2mafL4rLnBQ#).

[Mikeh]

I've heard that you can get some pretty lethal fumes from welding galvanized steel. Couldn't you get the same from using those knock down duct pieces inside the firebox? Maybe welding is in a different class of heat but that firebox sure gets warm...

[milkjugsapper]

Hi - First post...
Decided this year to try my hand at syrup making (haven't done it since I was a kid w/ my dad). Back then, we just used a lobster kettle over what was essentially an open fire. But boy, was it fun! Anyway, not having a lot of free time (or $$), I was hoping for something a little more effecient so I went with a block arch. I took ideas from the 'Backyard Sugarin' book and pictures in different places on the computer (thanks for putting them online, everyone!). Wish I had known about this site and seen this thread earlier! I put out 15 taps and had a real small scale operation. The arch has worked great with no firebrick. So far it has lasted through three boiling sessions and only needs to last one more. Although I often wished for more, I just had two buffet pans. Set the whole thing up in a sand box in our yard and ramped up towards the back with sand. Had some issues with high winds and snowstorms, but we've made about almost four gallons of syrup and are pretty happy with how everything went. Already thinking of improvements for next year! Look forward to learning more from all of you here at mapletrader...
- Ryan

http://i48.photobucket.com/albums/f201/bbpinecone/DSC_0916.jpg

[John c]

I've heard that you can get some pretty lethal fumes from welding galvanized steel. Couldn't you get the same from using those knock down duct pieces inside the firebox? Maybe welding is in a different class of heat but that firebox sure gets warm...

Does anybody know the answer to this?

[Groves]

Ironically, though pure zinc has a melting point of just under 800F, it doesn't pose near the danger of the zinc oxide gas that forms when welding/burning galvanized steel.

The stack would have to get above 1600F for me to worry about the zinc melting off and causing problems.

Indeed, vaporous zinc IS a problem, and more than one old-timer has walked to his death from carelessness (usually a welder/blacksmith, not a sugarer)

How hot do stacks get?

[Tonka Grove]

I dont know how hot our stack got this year, but it was hot enough to burn off the galvanizing the entire length of our 10 ft, 8 in stack. I kept smelling something funny, took me a hour to figure out it was the stack. After our first boil it was all burned off and didnt smell anything the rest of the season.

If I need to buy something to use for a stack again, it isnt going to be galvanized.