The Evolution of a Winter Stove – Part 3

> " I also use best practices to maintain a 'warm' canister before I start "
> tell me what you mean specifically by that.

See Bob's reply.

And here I though you guys were into something I didn't know… throwing around them fancy terms like 'best practices'… gee…

Billy

The purist would use Inconel; the pragmatist would use brass. Yep, some preheat tubes are brass. But a stove does not get as much use as a steam angine boiler.

Cheers
PS: YOU try machining Inconel. It's a nickel alloy.

Hi Duane

Yes, still in beta test, but that means I am looking for what can go wrong, not for any major design changes. As I have shipped over 60 stoves now, with only a few problems reported and all fixed, I am fairly happy with the design.

Plastic: yes, good stuff. NO intentions AT ALL of changing the plastic to metal. That wouldn't work, for a start.

The tiny screws: yes, they are small. Yes, you need a small Philips head screw driver to handle them, IF you intend to disassemble the connector. Such screw drivers come in little kits for a few dollars. Other stoves also have tiny screws. The ones on watches are even smaller!

The 'Main Ring' on the connector which is held in place by two screws. Yes, this can come off, but it should only do so AFTER the screws have been removed. If it is ripped off accidentally the screw holes will be damaged. Gently, gently with the rotating Spider is the message. If this has happened to anyone (or to their stove), please contact me. I will help to fix the problem. There are ways.

Cheers

Hi Jim

Odd, very odd. I would expect both of those canisters to work just fine.

Do you still have access to that stove, or does the owner have some Powermax canisters? I would like to ask for some photos of the stove in some VERY simple tests.

Could you get the owner to email me direct? Yeah, this is a beta test, but it should work OK. I WANT to know what the problem is!
[email protected]

Cheers

Hi Jim

OK, EJ and I will sort it out.
Such canisters work for me when tested over a number of stoves. May have been a 'learning' problem. Even so, I want to know about it.

Cheers

Hi Billy

> I've had lots of flaring.. From 20F to -15F.
In that case maybe you should bend the heat shunt a little bit towards the flame. Maybe just 2 mm movement at the top. This will get heat down to the stove body a bit faster. I do mention in the Instructions that you may need to do a litte tuning on your stove.

Cheers

Hi Roger,
so… pulled the jet… there was a little very light oily substance on the top of the jet… no light visible though it… got a hand lens and it is obvious that the jet is clogged… stuff so small it is hard to see, but looks like very very fine, gray metal shavings maybe… just packed in the jet hole… very few on the outside top of the jet so it must have been passing some..

that would explain the weak flame this morning when cold with lower pressure in the canister… and maybe at warmer room temp it may explain the very strong flame in that maybe the pressure coming from the canister at room temp was enough to blow those extremely find particles through the jet?

So my next question is WHERE do I find a copper wire small enough to clean the jet?
AND… do I have to know for sure that the wire is smaller than the 0.28mm jet hole before I go trying to push it through??? Any possibility that a copper wire will damage the jet hole?

Other things that concern me now:
If there are shavings (or whatever it is) inside the jet, there are likely shavings inside the jet holder, the fuel tube, and the spider connector. How do I clean all that???

AND where do these shavings come from???? The manufacturing process of the stove? Or the canister??? I'd like to avoid having this happen again… especially if I'm camped out in winter :(

thanks,
Billy

>wondering if you pre-warmed the canister and/or the heat shunt?

No, as I detailed in my post, both canister and stove were at ambient temperature.

But from your subsequent posts, it seems you may have isolated the problem (I hope). I'm sure Roger will follow up with a comment about the clog, but I thought I'd add that I made a canister-gas jet cleaner from a single strand of copper wire from an old twisted-pair Ethernet cable (not telephone station cable; that's too thick). I doubt such a fine copper wire would hurt the jet, because it's smaller than the jet, and softer than the jet material. Roger specifically cautions against steel needles because they're too big, and probably harder.

I used that wire on my Coleman Xtreme. Not sure what got into its jet, but it sure ran a lot better once I cleaned it out.

> I believe I am using quality canister fuel… Snow Peak and JetBoil…
There is some suspicion about the Jetboil canisters. They may be rebadged Chinese. The Chinese ones I tested were AWFUL: instant blockage. Does the label have specs for the fuel percentages? Yes, the label may be significant.

Oily stuff on top of the jet? That's out of the canister fuel. I've seen it before. It collects all sorts of gunge. It suggests a Chinese canister. You should also clean the needle valve tip in that case.

> [filter] getting saturated with liquid fuel and thus inhibiting the flame
Very doubtful if we are talking about butane and propane. Liquids from dirty fuel might do this, but I suspect not.

The dirt at the jet? Not sure whether it is actual dirt from the canister or fine aluminium swarf from the stove body. The latter may have come from the jet socket – unfortunately.

Filter paper: seems to be working well for quite a few people. Thus beta testing.

Cheers

Just caught up on this article and thread. Really impressed Roger. If I was planning a lot of Tassie trips in the next few years (no, baby(s), I'm grounded) or snow trips soon I'd jump on one, but you should sell your beta's to those who can test in the cold for you.

Have you considered what your next stove project will be? It would be cool to see you apply yourself to the super efficiency equation for above freezing stoves. Overall system weight efficiency, I mean. Personally though I love the convenience and efficiency of upright canister stoves, I'm torn by the use of canisters and the whole partial canister issue. On long trips (eg cycle touring Europe) its not much of a problem, but for trips of just a few days where I might need less than half a canister, it screws with my head. So I think I'll personally stick to alcohol for now.

+1 to Billy

I sometimes have a number of partial canisters of various weights to choose from which can be a nuisance

I do some car camping so I eventually get all the partials used

If I do a lot of trips that use a little more than half a canister it's more of a problem. For me that's 5 nights, and I've done several 5 night trips recently, but eventually all the partials will get used.

Roger… all my canisters say Made in Korea.

So it would seem that the blockage was from not enough cleaning of the stove on your end before shipping.

In any event I have not had another blockage since pulling it apart and cleaning the jet… (and using the same canisters)…. yet.

I did try your suggested coffee filter paper as a filter. But I don't think it works very well. Looked at it after using the coffee filter circle for a while and it looks to me like the pressure of the fuel entering at one side of the jet socket just pushes past the edge of the coffee filter paper circle.

What was wrong with the toilet paper filter anyway? Why did you suggest go go away from that?

Billy

Hi All

Herewith an update on progress with completing the latest batch of stoves. To explain
why: I still have some unfilled orders from enthusiastic beta-testers who have paid up front some time ago despite being told that there would be a delay due to my CNC machine dying and having to be rebuilt. My thanks to those people for their long-suffering patience.

I started to rebuild all the electronics on the the CNC, but a series of domestic
problems slowed me down. Our grey water dispersion system died (we live on a farm) and had to be rebuilt; a storm took the roof off our chook shed so it had to be rebuilt; our elderly LandCruiser suffered a pulley failure and there were NO spare parts left in Australia (we got the original pulley manufacturer in Japan to make one to the original specs), plus a few other small delays. Murphy strikes! But all of these have been solved. Hopefully, not too many more will happen.

The electronics for the CNC have now been completely rebuilt from scratch and have been tested. There were a few hiccups along the way as might be expected, but nothing
serious. As far as I can see it is now running again and I will soon be finishing off
the next batch of stoves. I HOPE!

To recapitulate: so far I have shipped
batch 1: 10 stoves with FMS-116T burners (all gone)
batch 2: 27 stoves with FMS-300T burners
batch 3: 22 stoves with FMS-300T burners
batch 5: 9 stoves with FMS-300T burners
batch 6: 8 stoves with FMS-300T burners to the 6th annual GGG
I still have some FMS-300T burners for the next batch, but my stock of them is fast
running down.

Cheers