> As I have written before I had problems with a MSR pocket rocket but thought that it might be either an user fault or just bad luck so I bought another pocket rocket for my CDT thruhike this year.
> Unfortunately, after 3 months on the trail (= about 200 uses of the stove) the same problem appeared and rendered the stove more or less useless. And at that point I was in the middle of nowhere with absolutely miserable weather and a non-functioning stove. I had a real problem!
Yes, this is a known problem, but it is not widely known. It applies to ALL screw-thread stoves. The problem is as follows.
The thread on the canister is roll-formed in very thin metal. It is NOT a complete thread by any means. (Pretty crude in some ways, actually.) This means that a high load is placed on a small part of the thread (the tip of the thread) on the stove. Since the thread on the canister is steel and the thread on the stove is brass (any stove), it is the brass which wears away. Eventually the thread stops holding and you can't get gas out of the canister.
Let me make several points here.
1) This problem applies to ALL screw-thread canisters and ALL screw-thread stoves.
2) You can minimise the problem by keeping the thread very clean and by not screwing the stove down hard. Screw it down lightly and see if the stove runs. If so, that is enough pressure. If not, do the thread up a little bit more. I think this may be where you are having a problem: you are using too much force every time. Be more gentle.
3) ALL screw-thread canisters have the same thread. ALL screw-thread canisters will mate with ALL screw-thread stoves - despite the manufacturer warnings you get with some stoves to 'only use OUR brand of canister or terrible things will happen'. This cross-compatibility is required by law.
4) Despite point 3), you may find slight differences between staoves and canisters which mean the different combinations have to be tightened different amounts. Yes, this happens. But they will inter-operate.
> With the same problem happening twice on two different MSR pocket rocket stoves I do not believe any more that it was a handling problem or just bad luck. I think that MSR is just delivering bad quality. I was never that disappointed with a piece of equipment before.
No, you are blaming MSR wrongly here. I agree that the pot supports on the Pocket Rocket are far too weak, but the thread is the same as every other stove. I think you have screwed the stove up too tight every time, and increased the wear on the threads.
The French Campingaz company did not like the screw-thread when it was developed by the UK firm Epigas, and developed their own system using a different fitting. It is a more reliable system, but seems to be mainly available just in France. The stoves are rather heavy - which is a pity.
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