Refilling Coleman PowerMax Canisters

It's no secret that I like Coleman PowerMax gas canisters.  Note:  PowerMax canisters are called just plain "Max" in some locations outside the US.

First, they're aluminum which means they're quite light. The canister weight (tare weight) of a large 300g PowerMax canister is less than the canister weight of a small 110g standard threaded canister.

An aluminum Coleman PowerMax canister connected to an Xtreme stove

Second, at least in the US market, PowerMax canisters have the very best cold weather gas mix available (35% propane/65% butane). Outside the US, I've seen Max canisters labeled 40% propane/60% butane which is better still.  That gas mix when used in liquid feed mode (as designed in other words) can run in temperatures down to -4F/-20C (per Coleman).

Unfortunately, PowerMax/Max didn't make it in the market place. Most people either didn't understand the difference or weren't willing to commit to a proprietary, non-standard canister. Much like superior BetaMax lost out to inferior VHS, PowerMax lost out standard threaded canisters.

For those of us with PowerMax appliances, what to do? Well, of course you can use an adapter, but that's extra weight, extra bulk, and extra fiddle. Wouldn't it be nice if you could simply refill the PowerMax canisters? Of course it would. But how?

Well, I don't have all the answers, but I have a couple of ideas that I thought I'd throw out there and see where they go.

First a simple idea. Take a Brunton Fuel Tool or the like (Snow Peak and Primus sell something similar).

A Brunton Fuel Tool

Attach it by some means to an appropriate fuel source.

A Brunton Fuel Tool attached to a donor 100% butane canister via an angled adapter

Then insert the fuel tool into the PowerMax canister.

A Brunton Fuel Tool inserted into a Coleman PowerMax canister

I've had good success with this technique with refilling Rando 360 cartridges.

CV360 cartridges refilled by a Brunton Fuel Tool

Unfortunately, the aperture on a PowerMax canister is wider than on a Rando 360 cartridge.

The connector on a Coleman PowerMax canister

This technique doesn't work very well with the Brunton Fuel Tool "as is." However, if one were to add some "O" rings and spacers (which I haven't tried yet), I think this technique would work well for refilling.

However, this would be a fairly manually intensive technique. The Fuel Tool requires pressure to release the internal valve. In other words, the valve of the Fuel Tool has to be held in place by hand in order to transfer any fuel. With a 100% butane 50g Rando 360 cartridge, this is no big deal. With a 300g PowerMax canister that requires two different component gasses, this could be a bit of a pain in the neck.

But perhaps there is another way.

Let's take a look at a Coleman "X" stove. They're all fairly similar. In this case, I'll show a Coleman Xpert stove.

A Coleman Xpert Stove

Now note how the fuel line comes in from the right. A nut affixes the fuel line from the canister to the fuel line of the burner.

I think that if one were to unscrew the nut shown in the below photo

The nut shown above attaches the fuel line from the canister to the burner

that one could create an adapter that would affix to the underlying threads. In that way, we could use the connector of the stove itself to attach to a PowerMax canister. This would be a non-destructive use of the components of one's stove.

Now there are other candidate ways to connect to a PowerMax canister. 
1. A Kovea TKA-9504 type butane adapter affixes to a butane canister via a "cam and fingers" system similar to the way a PowerMax stove connector affixes to a PowerMax canister. But alas the connector on a PowerMax canister is too wide to fit into the adapter's opening. Even if it were to fit, the adapter has no pin with which to depress the Lindal valve of a PowerMax Canister.

A butane adapter with a "cam and fingers" connector similar to a PowerMax stove connector

2. The base of an MSR SuperFly stove clamps on to the collar of a canister rather than screwing or otherwide attaching to the canister connector itself. The "clamp" does fit on to the collar of a PowerMax canister, but unfortunately, as on a TKA-9504, the PowerMax canister's connector is too wide to fit into the opening of a SuperFly's connector. You can clamp on, but you can't get any gas to flow.

A SuperFly stove clamped to a PowerMax canister.  Unfortunately the connectors are incompatible and no gas will flow.

Neither of the above two candidates for attaching to a PowerMax canister is really suitable.

It seems to me that the best connector for a PowerMax canister is the one we already have; the one that came with the stove.

The "cam and fingers" connector of a Coleman PowerMax type stove

I don't have the machinery and tooling to construct an adapter that would connect to the end of a PowerMax stove's fuel line, but I think that's where a good solution to the problem of refilling PowerMax canisters lies. I hope someone with the proper skills and equipment can make use of the idea.

Note that PowerMax canisters are NOT designed to be refilled.  Refilling a non-refillable canister like a Coleman PowerMax canister in inherently risky.  If you refill a PowerMax canister, you are doing something that was never intended to be done to that canister, and you do so at your own risk.  I won't try to lay out all of the issues involved, but if you choose to refill non-refillable canisters like a PowerMax canister, you should read up on the issues involved, understand the dangers, and be very methodical and careful.  Please note that my surmise that refilling a PowerMax is possible does not mean it's a good idea.

There you have it; my thoughts at this juncture on refilling PowerMax canisters.

Thanks for joining me on another Adventure in Stoving,

HJ

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Stove of the Week: Coleman Xpedition

Well, here's something I'd like to try:  A "Stove of the Week" post.  I doubt I'll be able to post a stove every week (but I'll try), but I collect stoves, I've got quite a number of interesting stoves, and I'd love to share them with you.  I take them out quite frequently in the winter, but when the temperatures climb, less frequently so.


Related posts:

• Stove of the Week:  Coleman Xpedition
• Stove of the Week:  Coleman Xtreme
• Update on Powermax Fuel 11/7/2011

For starters, here is the Coleman Xpedition two burner backpacking stove.  Yes, you read that correctly, a two burner backpacking stove.  Not many of those out there!

The stove is shown here on the ruins of Echo Mountain House a hotel built in the late 1800's atop Echo Mountain (3207'/977m).

Now the stove has something of a story.  First it came to me by way of a friend in England.  Ian sent it to me simply because he knew of my affection for and interest in this type of stove.  He asked for nothing in return.  I thank you very much, Ian, and I apologize that it's taken me this long to get it fettled (repaired) and posted. 

In terms of fettling, the "X" stoves that Coleman produced do have an achilles heel:  their connector.  I own half a dozen of the three types of "X" stoves (the Xtreme, Xpert, and Xpedition).  I've seen multiple problems with their connector (the point at which the Powermax canister attaches to the stove).


Basically, the canister has a hex shaped protrusion on it.  The hex is placed into the connector pictured above and rotated 1/6th turn to the right.  As the hex rotates, it causes the inner cam in the photo above to rotate with it while the outer "finger plate" (Coleman's term for it) stays stationary.  The protrusions on the inner cam force the "fingers" on the finger plate to expand and a small ridge on each finger is forced into a grove on the inside rim of the canister's valve assembly.  The fingers when forced by the cam into the grove hold the canister in place such that the lindal valve is depressed, opening the valve and allowing the gas to flow.  If you look closely at this photo, you can see the grove on the inside rim of the canister's valve assembly.

In theory.  In practice, however, the inner cam just wasn't rotating.  Instead, the canister's hex was rotating within the cam, stripping the plastic of the cam.  If you look closely at the photo of the cam, two photos back, you can see some wear where I've stripped the cam.  

"Well," thought I in all my full brilliance,  "the fingers must be too tight, and they're not allowing the cam to rotate properly.  I'll loosen them up a bit."  Crack.  One of the fingers broke off.  Oh, great.  

Well, no problem, I'll just order one from Coleman.  Nope.  Coleman no longer carries either the cam or the fingerplate.  Stumped, I laid the stove aside for a while.

Some time later, I was tipped off that Campmor.com carries "trail maintenance kits" for the Coleman "X" stoves.  The best deal is the Xpedition trail maintenance kit:  it has more parts (and for a lower price) than the other kits.  All of the kits are interchangeable even though some of the kits are labeled for one of the three "X" stoves or another.  A bit expensive to buy an entire kit for just the finger plate, but having no other alternative, I bought a couple.

Here in this photo, you can see the difference between a nice, new cam and a worn cam.

But no dice.  The derned thing still won't turn.   I tried oil.  I tried swapping parts out for new parts.  I tried powdered graphite.  Nothing I tried worked.  The cam just wouldn't turn.  I admit that at this point I just about binned the danged thing.  

Now, fast forward some months.  New Year's day 2011 is fast approaching.  Now, we've something of a local tradition hereabouts, it's called the Rose Parade, which is a nationally televised event.  As part of that parade, the US Air Force usually does a relatively low altitude fly by over the parade route.  Lately, it's been the B-2 Stealth Bomber.  Fascinating!  There's a mountain that has a commanding view of the parade route.  The last several years, quite a crowd has gathered upon the mountain top so as to have quite the view of the B-2 as it flies by.  It's become an event in its own right, with people bringing stoves, cooking, and having quite the festive occasion.  Well, if one wants to cook for a crowd AND one has to carry the stove up a mountainside, what better stove than a two burner Coleman Xpedition stove?  It's relatively light, yet it has not one but two powerful burners.  I thought, what could it hurt to pull the Xpedition off the shelf and have one more go at fettling?  

Now, take one more look at that last photo.  Note that the protrusions on the cams have sharp, hard right angled edges on them.  What if I beveled them a bit?  I got out a file.  I don't know how well this will show in a photo, but here's a cam after I've beveled the leading edges of the protrusions.


Now, have I just wasted my time yet again?  
NO BY GOLLY I HAVE NOT!!!         

Phew!  That's the best looking flame I've seen in a long time.  The worst part of it of course is after months of time spent and untold frustration, it only took me a few minutes to bevel the edges and have the stove up and running.   It's a fairly simple fettle -- once it occurs to you to try it.  Don't become a stovie if you're not prepared to have a good laugh at yourself once in a while.      

Well, then fettle done, off we go early the next morning.  We've got to make it to the mountain top and be in position before 0800 when the fly by occurs.  I'm carrying about 30 pounds of gear (about 13.5 kg); this will be no fast trek.  My friend calls.  He's running late.   Ack!  Off we go in a bit of a race against time!

It's a fairly cold morning by California standards; there's frost on the ground, indicating that the over night low has been below 32 F (0 C).

The San Gabriel Valley of California, pre-dawn.


Here's another view of the greater Los Angeles area from further up the trail a bit later that morning.  If you look closely at the uppermost of the two blimps, you can see the rose colored light of dawn.  Downtown Los Angeles can be seen at the lower right.


Finally, we're in position, and it's nearly 0800.  We've made it in time.  And there it is!  The stealth bomber!


Unfortunately, I couldn't get him in frame when I maximized the zoom level (he was moving too fast), so that's not the best photo in the world, but I assure you it was quite exciting in person.

Here's my set up on the mountain top after the crowds have departed.  I made hot water for instant oatmeal and instant cocoa for folks.  The Xpedition did an admirable job of it.


The pots are 0.9 L and 1.5 L Primus LiTech kettles.  Very convenient to pour from.  By having two burners and two kettles, I could serve with one while heating more with the other, allowing me to provide hot water to a fair number of people.

The canteen seen at left is an orginal Swiss military one produced by Sigg.  Sigg recently issued a retro version made of steel with a screw top.  I saw one go recently for about $75.00 on eBay!    I bought the original version for $7.13 total, and mine is lighter aluminum.  I think I'll stick with my version although a cork stopper is not as secure as a screw top, and I worry I may get water spilled on my pack some day.  I carry it strictly for the cool factor.     

The windscreen you seen in the photo is the concatenation of one and a half Olicamp windscreens.  One and a half windscreens makes an almost perfect fit for the Xpedition.
 

Here's the view from the top.  The signs you see are historical interpretive signs explaining the various features of the site.  The blue you see on the far horizon is the mighty Pacific Ocean.


And now that the crowds have gone, it's my turn to enjoy a cuppa.


And if you look behind me, you can see why so many people have chosen to live in California:  It's January, but it's a beautiful day.  It's cold, there was frost still in the shady spots, but out in the sun a light down jacket like the one you see me wearing was all I needed.  Not too bad for January.

Well, I thank you for joining me on my New Year's Day trip up Echo Mountain.  I hope you've enjoyed the trip -- and the stove.

HJ

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