Student: Caleb DesJardins

Mentor: Jeunghwan Choi


Can small scale blacksmithing operations achieve a level of efficiency in their forge comparable to that of a large scale industry? The causes for the lack of efficiency needed to be pinpointed, and then the geometry of the existing design for the burner could be changed to fix the underlying issues, while still maintaining functionality. The problems with the previous design is the geometry of the intake giving an unknown air/fuel ratio, and the attachment of to the forge allowing the intake air to be contaminated by exhaust gasses. A burner needed to be designed that would solve these problems while maintaining the ability to output an oxidising flame for when an oxidised workpiece is desired. The final approach for finding the optimal intake geometry was based on a ratio between the propane injector outlet area and the air inlet area. This ratio was calculated based off of the desired air/fuel ratio and the density ratio between air and propane. This approach was compared with flow rate analysis at various propane pressure settings. The result of this calculation is that for any set propane pressure, the height of the intake opening needs to be .232 inches high. The input pressure of the propane does not affect this result. The intake valve was still designed to be adjustable so it could still produce an oxidising flame as desired. The optimized burner can be attached to a forge by a flange that prevents exhaust gasses from entering the intake.


5 thoughts on “Forge Burner”

  1. Caleb,

    Looks like this was a great success! I would guess that the large reduction in oxidation will improve heat transfer, result in a better metallurgical structure, and overall reduce the amount of time needed to process the part.

    1. Thanks Joseph,
      The oxide layer is pretty superficial, so it doesn’t affect the metallurgy much. However, less oxidation does help a lot with time to process the part like you said. There’s also a lot less material loss during a forging operation.

  2. That so cool would love to see some videos of you forging something. Thats so awesome that you made it take 3 approx min less and used less propane. If you do 100 different forges you have saved yourself 300 min. Thats so crazy. Great Job.

    1. Big improvement, it’s really valuable to see things in that perspective of time saved over the long run. Starts to add up to an huge amount of time. Great project Caleb.
      Looking forward to seeing some of the projects you make with it.


    2. Caleb DesJardins

      Thanks Joshua,
      The time to heat improvement is definitely a plus, but I’m much more excited about the efficiency.

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