Would this jet resizing procedure mean that the Shmel 4 is a true multi fuel stove? If so, would you be willing to share the size of the needle and drill bit that you used? My Shmel 4 came with a spare jet, and being able to reliably run it on kerosene would make for one fantastic stove. Thanks again for sharing presscall
There’s a wide range of sizes for specific medical and scientific applications, but it’s the needle’s outer diameter that’s graded, the ‘bore’ is nominal. My guide is the Birmingham Gauge for hypo needle sizes, which gives the inner diameter for needles. A 26-gauge needle has a 0.26mm bore - I’ve confirmed this with a 0.23mm pricker - and a 24-gauge needle has a bore of 0.311mm should I need to restore a 0.32mm jet. For THIS repair of a Borde I used a 16-gauge needle, which had the dimensions I required. Latterly, my supplies are stubby needles without points intended for laboratory dispensation of liquids rather than injections. Inexpensive and a wide range of sizes. The Shmel burner would vapourise kerosene with a 24-gauge insert. Drilling a hole for it (reaming more correctly) is simply a matter of twisting with the fingers the mount of the hypodermic needle with a chamfered tip (to provide a cutting edge) against the existing jet orifice and it will ream it out and create its own clearance. The needle insert should then be silbrazed in place to prevent it being dislodged. The jet pricker didn’t require slimming down on mine, with clearance to spare. Had it not done so I would have got to work on it with an abrasive tip in a Dremel.
Thanks for all of this information, it really saves me a lot of time and effort. Very clever solution you have there.
