Mason fire box and other musings

[Boatman53]

For quite a while I have been interested in the Mason fore box that he talks about in his book Song Of The Paddle. This spring I finally got around to making some. I did buy a cheap sheet metal brake from Harbor Freight and it did work but not great and I could have used a work around.
At first I made the middle size because it was an economical use of the material I had on hand. Then I made the bigger one which seemed to be a better size, but made in steel it weighs about 4 1/4 pounds.. next I made the little one out of aluminum and it weighs a mere 1/2 pound. I did a burn in the aluminum and it held up fine at least once. Aluminum melts around 1200 degrees so keep that in mind.



Finally I made another one of the bigger box out of some titanium that I had. That stuff is tough I cut it with a jigsaw but used up a couple blades. Folding in the brake was how I started but the brake flexed (I did mention it was cheap) and in the end I had to finish the bends with a dead blow hammer because of the spring back. Here is a pick of the pieces, all the bends are 90° So nothing really complicated.



The first one I made I used a rack from a toaster oven to support the pots but the sides warped some in the heat so on the titanium one I made interlocking cross bars. They are light, pack flatter, and give great support to the pots and sides.
The last couple pics are of the titanium and that box weighs only 2 1/4 pounds. This is a step up from a twig stove for sure.
Here is the box in action. With a big pot of water boiling. The bottom of the box only gets warm so I can put it on stump and sit in a chair.


Things I like over my twig stove bigger wood so not the constant feeding the fire. Load the wood from the side. With a pot on top there is quite a draft going into the box. I find no need for other air holes and that reduces the chance of sparks or ember escaping where I might not see them. Plus a frying pan handle can hang over the side and not get unduly hot or sooty.
More of the musings in the next post.
Jim

 

[Cheeseandbeans]

Nicely done.

 

[alsg]

Now I want to make a titanium reflector oven...

 

[Boatman53]

I’m not sure titanium is actually lighter than aluminum but it is stiffer. I had a hard enough time just making the 90° bend, I can’t imagine trying to roll it around a wire for a hinge.
So now I need a bag to store it in. It is a little sooty but the way it packs down all the sooty surfaces and protected. Initially I made an aluminum poker but after using it for a while I discovered some ice tongs from the thrift store made a much better fire management tool.



And here is the bag. It holds a cotton rag, the tongs and a pair of leather gloves.


I might even throw in a match safe or ferro rod.
Jim

 

[Boatman53]

I got thinking last night after my comment about including a match safety kit that I could cut a couple sheets of birchbark (I have a lot from my firewood pile) to lay flat with with everything else. It would always be there when needed.
Now for some of the musings. While frying up some bannock I was remembering that during the 18 months I lived in a wall tent in northern Idaho the Sims sheep herder stove I had made an oven that would attach to the side of the wood stove. I didn’t buy it as I already had a reflector oven. So I started to think along the lines of making an oven to work with the fire box. I did my usual CAD (cardboard aided design) to see if it was feasible. Sorry no pics of that process but here is the first version. It actually hooks over the side of the box and has an aluminum shelf to hold the muffins. In this experiment the lid is just resting on top and is not attached.



It was a success. It baked the muffins nicely, but checking temps with a thermometer the heat radiating to the bottom of the oven was quite a bit less. I also think the solid aluminum shelf blocked some heat even though I left a lot of space on the sides.


But if you are not paying attention the temp can spike.



It was a success but there were some drawbacks. It had to be used with the box, it was not a stand alone oven. So back to the drawing board. This is what I built next.

It’s free standing and can be used with any fire. I set it up at the end of the box so flame heat can radiate to all areas of the box. The firewood can be placed vertically leaning up against the cross bars of the firebox. It baked better and is more versatile. I’m good to go for my BWCA trip in September..
I’ll do a whole different thread on building the oven.
Jim

 

[alsg]

Very professional looking!

 

[Tryin']

Solid project! Nicely executed.

 

[scratchypants]

Fellow Canadian made one from a cash box:

 

[Boatman53]

Did some more learning with the firebox reflector oven combination today and baked peanut butter bread with chocolate chips. Turned out pretty good, but the bottom and sides were just a bit on the over done side. Baking a bread like this I guess I need to have the oven just a little bit further away from the fire. The firewood pail is 8” in diameter and for the hour bake I used all but 4 pieces. Very economical, I think.
Before baking.

During the bake.

Out of the oven.

Out of the pan.


Jim

 

[coldfeet]

Wow! Very cool Jim! Guessing once you get tinkering there is no limit! Wonder if you can supersize it? My wife hates our stove/oven in the house. Hmmm do you make house calls?

 

[Rubbaboo]

Hey Jim, super interesting projects!
I‘ve a couple of questions if you wouldn‘t mind.
What are the dimensions of the bigger box?
What gauge of titanium did you use?

 

[Boatman53]

Hi Rubbaboo questions are good. I cut the blanks starting with the outer tray and that is 10”x14” I drilled a small hole at the apex of the corner cutouts in the hopes that it would help relieve any bending stresses. The sides that were folded up are 1”. So the outer tray when folded is approximately 8” x 12”, approximate because the folds are not right on the mark, or hard corners.then everything is sized to fit inside that. The inner box I tried to make smaller by the thickness of the sides that will fit between when assembled. So the blank for that box was cut cut just a bit smaller including the height of the sides when folded. I didn’t want them night than the outer box. On one steel box of this size I cut the width of the side a little narrow and felt it restricted loading own a bit so the titanium box has sides that just fill the inner tray when packed, and one of the sides is shorter in length to account for the fact that it has to nest with the other one.
The thickness of the metal is .027 on my dial calipers, but I don’t know what grade grade it is as it was given to me by someone that only knew it was titanium.

Coldfeet, I guess you could supersizes it but what a bonfire you would need. Maybe drag your house oven outside, open the door, put in the food and then build a fire on the door. Of course you would have to time the fire to go out just when the food is done as there is no way to reach over the fire. House calls might be possible as I know bagels would be involved. But if our friendship has taught me anything is that you are rarely home! I bake something when you come up here.
Jim

 

[Boatman53]

Another detail I learned from making the steel ones was to slightly radius all the corners, before folding. It makes it much nicer to handle and slides into the bag easier.

Jim