The Self Feeding Fire is a novel option for solving the age-old chore of feeding a fire. Properly constructed, this type of fire will burn through the night warming those close by without the constant need of tending. Whether you are an avid outdoorsman or weekend warrior, this campfire design will impress and perform.
NOTICE: This is not a "Survival Fire" and can be best described as impractical and unnecessarily complex. Only attempt this type of fire with fire safety equipment at hand and with constant supervision!
Check out these steps and watch the video at the end to see it in action!
Step 1: What You'll Need
Some assembly is required for this set-up and an assortment of tools / parts must be gathered to get started. The list of items are as follows: a shovel and/or trowel for digging, rope or cordage for lashing, strong straight stays for the support frame, as well as a number of large diameter smooth logs for fuel.
Review the pictures on this step for clarification and additional details.
Additional tools or substituted material may be needed along with fire suppression gear for safety.
Step 2: Preparing a Location
The fire pit setup should be built in a location that is open and clear of flamable plants and materials (as should all fires). The pit itself must be dug in a specific way for this type of fire to work. The rough dimensions are as follows: The length of the pit needs to run 5-6 inches longer than your largest fuel log. The width of the pit will depend upon the diameter of your fuel logs. Before setting up the frame, two fuel logs should be able to set within the fire pit side by side with little room to spare. The depth of the pit can be from 6-8 inches.
Make sure you pile up the dirt along the long sides for use in a later step.
Step 3: Lashing the Frame
The frame for this fire requires two sides, each consisting of two upright stave and one horizontal stave lashed together to resemble a capital H (as pictured above). The uprights need to be spaced so that they are wide enough to act as ramps for the fuel logs to feed down into the fire. Make sure to remove any bumps or rough areas that might interfere with the fuel logs sliding.
To bind the frame together, I prefer to use a square lashing with 1/4 inch sisal rope for assembling these frames.
Substitutions can be made per materials as long as this fire design is fully understood and all is accounted for. Fasten the frame well, make sure the rigid parts are strong enough to bear the weight of the wood and the ramps smooth.
Step 4: Line the Frame Up
Once you've lashed both parts of the frame, you'll want to line them up with the prepared pit (as shown in the pictures above). Lining the frame legs up will indicate the locations where holes must be dug in the next step.
Make sure that the lashings are tight and make any adjustments at this point as the frame will be raised shortly after this step.
Step 5: Footing for the Frame
You will need to dig a shallow footing to set each of the frame uprights in. These holes need to be slightly larger than the upright post's diameter and partially dug into the pits side walls.
Step 6: Raising the Frame
The frame can be raised by setting the frame poles in their footing and lifting the horizontal cross piece. Bracing poles must be propped beneath and behind the frame poles. Each side must be evened out and raised until the inner angle of the combined ramps reaches 90+ degrees. Ground angles at ~45 degrees.
A dirt/clay layer needs to be packed around and up the base of the frame uprights. This dirt barrier will insulate the vulnerable wood from the heat of the fire.
Step 7: Loading the Fuel Logs
The initial fuel logs must be placed and prepped so that they light in a specific way. A gap of an inch or so between the first two logs can be made and kept open by placing a few wedges between the two logs. The gap allows for uniform ignition of this fire and access to set tinder and kindling down into and beneath the space between logs. The fire must be made to contain the flames along this space on the inside edge of the initial fuel logs.
Failing to contain the flames between the two logs will lead to a critical failure... which will likely result in a bonfire.
Step 8: Sealing the Dirt Ramps
Before fully loading the fuel racks and lighting, the dirt behind the ramps must be formed up to create a seal. The dirt seal's purpose is to stop the air from flowing under the fuel logs, this will keep the heat from moving out and up the logs backside which would eventually lead to an uncontrollable blaze.
The trick to this fire is to control the amount of air and its source. Heat travels up, let it escape on your terms.
Step 9: Ready to Burn!
The frame should be ready to be loaded with fuel logs once the fire starting material is in place. All must be checked before this system is ignited. Once begun, the fire is designed to tend itself until the last of the fuel feeds down the ramps over the course of many hours.
Safety measures should always be in place when handling fires. A poorly executed build of this project, as well as the ever present risk of starting fires, mandates that this should not be attempted without knowledgeable and experienced supervision as well as fire control tools.
Step 10: Ignition!
The fire must be started along the entire length of the fuel logs. The logs must burn evenly for the logs above to feed correctly.
Be safe with fire and be prepared to fail at this the first time. This system is rather impractical and unpredictable in its construction and use... but it can be done, and sometimes there is worth in being able to accomplish a thing just to say that it is possible.
Step 11: Watch This Video to See How It's Done
Not a step, but if a picture is worth a thousand words, then a video ought to be worth at least a thousand pictures. Click on the video above to see how it's done. Check out my YouTube Channel to see more videos like this one: Bob Hansler https://www.youtube.com/user/horsebackbob