The Fire Maple Fms-118 is a nice looking and cheap stove which, on first look, seems to be a good option for winter use with an inverted canister. My testing revealed a sputter issue when inverting the canister for cold weather use, which the I posted about earlier, but I think i've found a fix.
Following some advice from user Stuart R in this thread on backpackinglight.com I worked a bit of wire into the preheat tube to reduce it's ratio of internal volume to surface area. This proved to be a non trivial operation thanks to the sharp bends in the tube, but I found something that worked and the supplies I used and steps I took are below.
I haven't had a chance to test this extensively in cold ambient temps but the mod eliminates the sputter when tested with a canister fresh from our freezer. The Fire Maple now seems almost as sputter resistant as the MSR WindPro II, though the Windpro stove still gets my vote in the "Designers Clearly Knew Their Stuff" Category.
I'll do some more testing with the Firemaple next time we get temps bellow 20 F at the house but the Windpro is the stove we will take into the mountains when we expect it to get that cold.
- A selection of stranded copper wire to make sure you find a size strand that works.
- Wire strippers.
- Small pair of long nose pliers. I used the one from this Crafstman set from amazon.
- Yellow Thread Seal Tape (yellow is for use with gas lines).
- Small crescent wrench.
- Wire cutters and scissors.
- Strip six inches of wire and cut off one six inch long strand. Save the other strands incase you mess up and bend the first one.
- Remove the fuel line fitting from the burner assembly. I actually disassembled the entire stove but this is unnecessary.
- Begin feeding the strand into the pre heat tube. It will be stopped by the bend almost immediately.
- Using the long nose pliers grasp the wire as far inside of the burner assembly as you can and push it into the preheat tube. Be methodical and only feed in about 1/8-1/4" at time. Any more and the wire might bend instead of pushing into the tube. Once a wire bends it is difficult to keep feeding it.
- Feed wire until you can't any more. I fed enough wire into the preheat tube to reach just past the upper bend before I bent the wire and was unable to continue.
- Cut off the excess wire leaving enough to pull the wire out if necessary but not enough to reach past the metal fitting on the end of the fuel line as the wire could get hot enough to melt the plastic inside the fuel tube.
- Cut a narrow strip of thread seal tape and wrap the threaded fitting on the end of the fuel line.
- Slide the fuel line fitting over the wire and reinstall it into the burner assembly.