This is the third of a series of three discussions about three improvised wood-fired “rocket” cook stoves I have made for my own outdoor use. In all three types, the stove top is at a convenient elevation above floor/ground. What I have done for my own use should not be construed to be advice to you or anyone else. Seek the advice of a safety professional regarding proper safety precautions for your situation.
The wood used in these stoves includes 4-ft long pieces of broken branches, stove-wood length split fire wood for use in traditional cast iron wood-fired cook stoves, and short chunks of branch wood where chunk diameter and length are about equal. Wood diameters less than ½ inch tend to burn out too fast and diameters greater than 2½ inches tend to burn too slow.
My rocket stoves are less expensive, but heavier and less portable, than commercially available ones. My stoves utilize locally available home & patio construction materials such as fired clay bricks, concrete patio pavers, concrete building blocks and assorted pieces of scrap metals. In their simplest forms, they require no tools to build. My more “elegant” versions require ordinary hand-held home maintenance tools such as a metal cutting hacksaw, drill, and pop riveter.
Type I discusses the simplest stove – the one where the cooking utensil (kettle, pot, skillet, griddle, or grill) is supported by the stove itself and the entire stove is constructed on a roll around cart so it can be stored in one location and used in another.
Type II concerns four variations of a more complex version of improvised stoves. The common feature of these variations is that the weight the cooking utensil is supported on a separate structure that is cantilevered from a porch railing and over the stove. The stove supports none of the weight of the utensils. This feature was developed to minimize the risk of toppling the stove when heavy utensils are placed onto the stove or removed from it. This cantilever arrangement is not mobile.
In the simplest of these four variations, the sides and handles of the cooking utensils are exposed to the flames of the stove. In the second version the sides and handles of the utensils are shielded from the flames and the cantilever includes a simple temperature control device that is important for safe operation of pressure cookers/canners. The third version shows use of a Dutch oven on the cantilever over the stove. And, the fourth version shows an improvised baking oven on the cantilever.
Type III concerns a semi-permanent installation that is somewhat reminiscent of an old-fashioned wood fired cook stove but, while heavy, can be disassembled, transported from one location to another, and quickly reassembled by one person with a wheelbarrow or pickup truck.
Type III – My front yard rocket stove cooking facility
I use rocket stoves for front yard summertime cooking. They consist of 2 parts: (1) a support structure to raise the stove to a convenient cooking height; and (2) the stove itself.
Rocket Stove Support Structure
The support structure consists of 2 piles of stacked concrete building blocks. The ground is leveled so the tops of both piles are even and level. Atop these piles are 2 parallel angle iron bars (1 ½” x 1 ½” x ⅛”) by about 34” long. Three concrete patio pavers, 12” x 12” x 2”, are set on the bars as shown in photos 1 and 2. The rocket stove is built atop the support structure.
Multiple versions of rocket stoves can be used on this type support. The first version (photos 3 – 8) is 2 bricks long. It’s meant for supporting a canning kettle. The second version (photos 9 – 12) is 3 bricks long and is for supporting a 2 burner cook stove top salvaged from an old burned-out cast-iron wood-fired cook stove.
Canning Kettle Support
In photos 3 – 6 note the brick arrangements in three tiers. It’s the same as for preciously discussed versions of my rocket stoves.
In photo 5 two pieces of salvaged 1½” x 1½” angle iron are place atop the brick structure. Then, in photo 6, a steel plate with round hole is placed atop the angles. This plate shields the sides and handles of the kettle from flame and soot.
Photo 7 shows the kettle atop its flame & soot shield before and after ignition of the heating fire. In photo 8 the kettle contains 4 gallons of water and was brought to a rolling boil with 30 minutes after putting a match to the fire’s kindling.
Support for a Salvaged Cast Iron Cook-Stove Top
Photos 9 & 10 show short pieces of 1” square steel tube are used to support the cook top. The angle iron supports used for the canning kettle could have been used. This cook top has removable lids.
In photos 11 & 12 the fire has been built. The stove top lids can be removed to obtain faster heating of the pots on the stove or replaced for slower heating.
Also notice the flame coming out from the stove side. If you have another piece of square tube it can be placed in this space to protect your belly from the flame if you stand close to the stove side. Just leave the opposite side open for venting stove exhaust.
The entire cast iron stove top can be removed from its support structure and replaced with a griddle or a grill or left open as desired.
Photo 13 below shows as expansion of the single rocket stove described above. The stove at the right is topped with grill consisting of a salvaged cast iron steel gutter drain. It can be removed to allow use of other utensils.
Photo 14 shows the stove with pieces of long firewood in and next to the stove. They were made by taking fallen branches from oak trees and breaking them into about 3 – 4 foot lengths rather than cutting them with a saw.
Photo 15 shows an easy way to break small branches. Simply place the branch in the V between two closely spaced trees. Place the desired break point in the V with the small end of the branch on the far side of the tree. Then grasp the large end and pull it horizontally until it breaks. They generally break right in the V provided that the branch is not green. Recently cut green branches do not break cleanly. Branches that have once been dried thoroughly and then dampened by rain or snow generally break cleanly but may be difficult to ignite.
End of Installment 3