Experimental Homestead

The Mega Canner: Every serious canner needs one

Canning season is upon us.  If you ever find yourself having a long day of boiling batch after batch of jars on the stove top, you need a bigger canner!

smiley underdog firing up the bark boiler full of shredded tan oak bark for tanning goat skins.

smiley underdog firing up the bark boiler full of shredded tan oak bark for tanning goat skins.

Many years ago in my blacksmithing obsessed days I was often found cruising metal scrap yards for treasures and steel stock.  Every time I’ve moved, my accumulated scrap pile has come with me.  One day I spotted a large stainless pool filter, complete with lid, at my favorite scrap yard.  I knew right away that I wanted if for boiling large batches of oak bark for tanning hides.  I figured it could be useful for other stuff too, so I bought it for a mere 20.00.

It took me many years and quite a few moves with the scrap metal pile in tow to finally get my bark boiler running.  I put a scrounged copper pipe and a gate valve on the bottom outlet and fired it up to boil some bark.  My suspicions that it was awesome were definitely confirmed.  An open fire can be used directly under it which saves a lot of propane, and when cooking is completed, the liquor can be drained off from the bottom.  Using the bark boiler is a huge improvement on boiling batch after batch of shredded bark on the stove top.

The bottom of the Mega Canner.  The elbow fitting is bronze, the pipe is copper and the gate valve is bronze.  The gate valve eventually failed, but i don’t think it had anything to do with inappropriate use.

The bottom of the Mega Canner. The elbow fitting is bronze, the pipe is copper and the gate valve is bronze. The gate valve eventually failed, but i don’t think it had anything to do with inappropriate use.

I had the boiler running for a year or so before it ever occurred to me that I could use it for canning food.  I needed to pasteurize some fermented grape juice in the bottles and they wouldn’t fit into a canning kettle.  So, I busted out the bark boiler. Amazingly, 19 champagne bottles can fit in the bottom layer, with room for another layer above that!  The experiment went well, so the bark boiler donned its second hat, that of Mega Canner.

Pasteurizing grape juice

Pasteurizing grape juice

Tomato canning can be a big production around here.   We shoot for about 100 pints a year and they come off the plants in large batches.  Half the day in the kitchen blanching, peeling and packing into jars and then all those suckers still have to be water-bathed.  Try this scenario on for size (I’m sure a lot of you have) Fit as many jars as you can in the kettle, boil the kettle for 45 minutes or more, turn off, allow to cool somewhat, remove jars, allow the water to cool a bit, add new jars, bring back to a boil, and repeat it all over and over again while dragging your timer around the property trying to get other stuff done.  It’s often hot and the kitchen gets steamed out.  The Mega Canner can fit hours and hours worth of water-bath canning into one firing that doesn’t take much longer than canning one kettle of jars on the stove top. The Mega Canner has room for a helluvalotta jars holmes!  If it can fit 38 champagne bottles, imagine how many quarts or pints it can hold.  I don’t know.  I’ve never come close to filling it up and I’m too lazy to bust out cases of jars to find out.

One days canning.  There are over 50 pints here.  That represents many batches in a stove top canner.

One days canning. There are over 50 pints here. That represents many batches in a stove top canner.

The Mega Canner/Bark Boiler could also be used for distillation with some very slight modification and to boil all manner of large batches of stuff.  It started its life as a pool filter.  Stainless pool filters are fairly common, but most are pretty small in size.  This is the largest one I’ve ever seen, though it seems likely that they are made even larger.  The walls are very thick, much thicker than a pot or a barrel.  It has a perforated grate on the bottom which is mighty handy for both bark boiling and canning.  It does still smell of chlorine a little.  Steel is minutely porous and chlorine has probably bonded with the surface of the metal.  I may at some point sand off a thin layer of metal from the inside to get rid of that.  for now though, no food contacts the water or metal.  There are various grades of stainless steel, and the metal composition of this one is unknown, so it may not even be food grade.  Finally, the drain pipe and plumbing on the bottom are bronze and copper which are not food safe either. There are two drains on the bottom.  One drain is plumbed already and the other has a bronze cap.

It even came with this handy perforated grate!

It even came with this handy perforated grate!

To use with a fire, I set the legs on 3 bricks or rocks to raise it a little.  This system could use some improvement for efficiencies’ sake. A rocket stove furnace which it could be set over would be pretty ideal.  A rocket stove would be cleaner (complete combustion), faster, and would use much less wood.  That project however will have to wait for a permanent outdoor kitchen to be built.  When its dry out and high fire season, which is almost half the year, a propane burner from an old smoker substitutes for the fire.  The burner is super high output, so you can really crank it up for fast heating.  A piece of aluminum flashing is used as a windscreen with the propane burner, which really helps keep the heat under the pot.

Propane burner and windscreen for dry weather use.  Don't worry, I'm not going to fire it up in that dry grass!

Propane burner and windscreen for dry weather use. Don’t worry, I’m not going to fire it up in that dry grass!

I have seen quite a few other pool filters at scrap yards and such since then.  Most are pretty small, but some are large enough to be useful as canners.  Craigslist has a lot of them, but most of them are not very useful shapes.  A lot of them have lids that are as tall as the bottoms, which is fairly useless for canning.  Some look as though they are made from other materials, and even the stainless ones are often painted, but persistence in hunting pays off and there must be more similar to mine out there.

I think a better option for a lot of people might be a full sized stainless steel beer keg.  The larger size known as a half barrel is 16 x 23 inches, though it has less actual inside working room than that due to the standing rims on the top and bottom.  Cut the top off, have some handles welded on, and you’ve got a good sized food grade stainless cooker that you can also use for scalding turkeys and chickens for plucking, and for who knows what else.  I would add a heavy stainless or aluminum screen or perforated plate for canning as the jars must always stay off of the bottom of the canner.  Stainless drums are fairly common too.  They come in sizes from 15 gallons and up,  A 30 gallon drum with copper/bronze plumbing for a bottom drain and a lid ought to make a fine large boiler that would fit almost any amount of stuff a body desired to boil at one time.  Of course stainless isn’t essential if you aren’t cooking food or tanbark directly in it, so there must be other items out there of aluminum or steel that could suffice.  The bottom drain is also not essential, just convenient… unless you want to put it on a stove top, then it’s actually inconvenient.

not every one cans large amounts of jars at once since that requires large amounts of food to be canned, and I only do so a couple times a year.  But, if you are into homesteading, or are serious about subsistence activities, you probably will sooner or later.  I’ve often had two stove top canning kettles running at one time, and that helps with the time and hassle when processing a lot of jars, but Mega Canner still kicks major butt on that scenario if there are a lot of jars to boil, such as when processing a bumper tomato crop or canning juice.  If anyone wants to take my bark boiling mega canner away, they’ll have to pry it from my cold dead fingers.  If you do a lot of canning, or plan to in the future, put large metal containers on your radar!  That is probably my best canning tip besides don’t can stuff you don’t eat.

I harvested over 50 pounds from one Polish Linguisa plant in that season.  It isn't the best tasting tomato out of the lot though.  My favorite is the little yellow ones in front, Orange Banana.  They have a sweet fruity flavor.  The reds tend to have more a tomatoey flavor, which is good for some uses, so I grow both.

I harvested over 50 pounds from one Polish Linguisa plant in one picking on this day. It isn’t the best tasting tomato out of the lot though. My favorite is the little yellow one in front, Orange Banana. They have a sweet fruity flavor. The reds tend to have more a tomatoey flavor, which is good for some uses, so I grow both.


July 21, 2013 - Posted by | Food and Drink Making, Uncategorized


  1. You have no idea how much I lust after this. The second I saw the pic. I mean really. And you put this up right before tomato season here when I’m not likely enough time to source. Pure evil. ;)

    Comment by c. | July 21, 2013 | Reply

    • You can find a beer keg easy enough, but you still have to cut it and stuff. It’s probably doable though. I was thinking maybe a sawsall to rough cut the opening to fit a large pot lid and then file down to the exact size. Shouldn’t be that hard with a good new half round file. I’m not sure what to do about the rim on the bottom, but if you put it on an open fire, it would probably be an advantage even. I passed up tons of beer kegs in my early years because I thought they were all aluminum. They’re all stainless though as far as I know. They just look like aluminum sometimes because they’re all beat to hell which gives them a dull oxidized look. Anyway, there are a lot out there.

      Comment by Stevene | July 21, 2013 | Reply

  2. Brilliant! I have been wishing for some sort of serious vat to do my canning in, but the idea of searching for pool filters or other metal things that did not start their lives as kitchen accessories hadn’t occurred to me!

    Comment by jj | July 21, 2013 | Reply

  3. Bad Ass!!! That is some serious repurposing for a great price. As far a using a beer keg, your readers should be warned to bleed out any excess pressure from the keg before doing any cutting! Worse case senario would be a possible shrapnel wound, but more likely you would just get covered in old, nasty beer. I use an old 1/4 barrel myself – a bit smaller than the half, but still pretty good, but I think it might be time to upgrade! Thanks again Steven!

    Comment by autonomyacres | July 21, 2013 | Reply

    • Andy, what did you do about the rim on the bottom?, or was there one? I’m thinking that a revere ware style lid of a very large size and a hole cut to fit it exactly. Not as versatile as my pool filter, but should be pretty dope. Also, if one wanted to get really crazy, you could add a stainless valve. Imagine heating juice to pasteurization temps and draining straight into sterilized bottles. Very cool. I might just make the 1/2 barrel keg I have for fermenting into one. Seems like a handy in between size. i can’t tell you how much we use the crap out of all of our large stock pots, but they are often still too small for that huge batch of bone broth or whatever. Repurposed kegs seem like a great way to fill the gap.

      Comment by Stevene | July 21, 2013 | Reply

      • I ran my bulk head out the side right above the rim. This was an intentional design because the kegs main use is my mashtun/kettle for homebrew. By having the bulkhead a elevated just a bit, rather than on the bottom allows me to drain off the wort while the majority of the hops settle to the bottom. Stainless steel ball valves are awesome (and expensive) but most of them can be taken apart and rebuild – a quality not seen often these days.

        For some cool ideas check out Randy Moshers’ book, Radical Brewing. He built a home brewery out of all scrapped and repurposed stainless and copper, and it is awesome! A lot of it could be useful in with hwat you and others are doing. I will try and find some pics if I can…

        Comment by autonomyacres | July 21, 2013

      • It seems like the bulkhead would be best welded in, how did you deal with that? Does having the rim intact interfere with stove top use? This propane burner I have is bad ass. It sounds like a jet, very high output regulator. It is off a metal canister smoker and came with a stand like you might find with a crab boiler. Very handy. I’ve seen more of the smokers for cheap since then. I think it’s the kind of thing people buy, but don’t really use much and then they end up rusty and thrown out of sold at the yard sale.

        Comment by Stevene | July 21, 2013

      • My bulkhead is not welded, but it is an upgrade I would like to do. I need to find a welder who can do food grade TIG welds. I know they are around, but I just haven’t looked that hard. I have never use my “kegettle” on the stove, just a propane burner that is probably similar to yours so I have never had a problem.

        Comment by autonomyacres | July 22, 2013

      • How is it attached? We have lots of stainless welding outfits around here because of the wine industry.

        Comment by Stevene | July 22, 2013

  4. This is awesome!

    Comment by Sarah | July 21, 2013 | Reply

  5. Oh my. I end up running my fowlers vacola water bath and the pressure canner as a wb plus a saucepan to start bringing the next lot of jars up to temp so I don’t need to let the water cool or change it down. It’s a nightmare! We try to do 50-70 jars of tomatoes too in quart sort of sized bottles (the fowlers vacola system is different but the #31’s are nearly a quart and the #20’s a pint. Not sure what the #27’s are though, not quite a quart I think) and it ends up being days of stinking hot house and tomatoes wilting in the heat. I put up 40kgs of tomatoes into tomato paste, sauce (ketchup) and then diced toms too although I don’t blanche and skin. It’s insane. This baby of yours is like a dream come true! Hubby!!! There’s 7-8 months til tomato picking time…

    Comment by rabidlittlehippy | July 21, 2013 | Reply

    • I blanch peel and can all tomatoes whole. I have made ketchup, but I still have a 10 year supply. I find the whole canned are very versatile and take mabye 20 minutes to cook down into sauce if that’s what I want, but it usually itsn’t. I’m interested in the Vacola system and looked into it a little after seeing it on your blog. Our system here kind of sucks because it’s very expensive and the food contacts the PBA lined lids. I think we can do much better. The German Weck jars are Ok and the bail style European ones are Ok, but the lid gets in the way a lot and they are hard to open.

      Comment by Stevene | July 21, 2013 | Reply

      • The Vacola jars are awesome and are fine to use in pressure canners. I have a presto and no issues whatsoever. The stainless steel lids can be pricey compared to the tin ones but worth the investment for me. As for the jars, FV make very few of the different jars these days sadly but second hand sales are great. I buy mine from a couple in Ballarat and pick them up but there are some good deals on eBay. Just don’t buy a clip for every jar, just enough for however many you can feasibly can in a day. The clips come off after 24-48 hours. the other great thing is that it’s all reusable aside from the rubber rings although I do reuse mine (not recommended though) and I’ve not had any problems to date. The rings are ultra cheap to replace too.
        We use diced tomatoes a lot so I just found it easier to dice them skins on. I can then render down to sauce or paste easily too. Next year I think I need to double my tomato bottling though. More paste is needed!

        Comment by rabidlittlehippy | July 21, 2013

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: