This time I will try the lower tornado of the frame stove. The flame can be changed by attaching a variable tornado ring. Introducing a digest of tornado ring production. Draw a line on the stainless steel plate. Mask and mark the secondary combustion hole. Replace the masking tape and punch a hole with a carving blade. Press the hole with a round bar. Cut with scissors. Fasten with bolts to form a ring. Enlarge the hole with a mini router. The tornado ring is completed. Move the ring to adjust the secondary combustion hole. It tornadoed beautifully. I tried to move the tornado ring to observe changes in the flame, but the ring thermally expanded and did not move. When the tornado ring is cold, it will fit smoothly, but you will need to make the fit even looser. The handle of the ring has also been changed and now has two handles. The fit has been made even looser. This makes it easier to move the ring even if it expands due to heat. Check combustion. The fuel is pine pellets. Add fuel alcohol to promote combustion. Since secondary combustion has appeared, I put on the fire ring. Now that the tornado is stable, move the ring to vary the flame. By moving the tornado ring, the secondary combustion hole will be fully closed, half open, or fully open, and the flame shape will be a combined flame, a straight flame, or a tornado flame. The table shows the state of the secondary combustion hole and the changes in the secondary combustion flame. Fully closed produces a combined flame, half-opened produces a straight flame, and fully opened produces a tornado-like flame. Although the flame is a tornado, I believe that by rotating it, the mixing of unburned gas and air improves, increasing combustion. That's all for DIY variable tornado ring.
