I did talk to Campmor a few days ago but by the time I add shipping I don't save much vs buying local. Two local store have the 300 gr canisters and one of the stores sells it at $2.99. I think that is a bargan but have never seem the smaller canister for sale. I haven't been able to find the smaller canister anywhere near me.

I think the Coleman Outlet Stores sell the Xtreme at the Campmor price and this weekend coming up they are having a big Tent Sale with most of their stuff on sale.

Paul and Bill,

I think that this is the normal price for Campmor. I bought mine (for that price) at the store and picked up the larger cannisters as well for $4.99 each I believe in July. I am not sure if they have the smaller canisters. But, if Bill was able to get the smaller cannisters for $2.99 each, I believe that to be a very good price.

Rich

Bill,

I will be very interested in the modifications for the Coleman Xtreme that you come up with. Hopefully, at least some of them will be simple enough for even me without the right tools to make.

Rich

I can buy the large (300gr) PowerMax canister for $2.99. If you have a Sportsmans Warehouse near you that is where I bought mine.

Bill,

We don't have any Sportsman's Warehouse in Eastern PA. One will open in Pittsburg on November 23, but that is 400 miles away. $2.99 for the 300 g canister sounds like a great price. As I indicated, Campmor's price when purchased last was $4.99.

Rich

Richard, Don't ask me how many I bought at the $2.99 price. I can say that I did leave one for the next person.

There has been a good Thread on the Xtreme stove at the backpackinglight yahoo group the last couple of days. Information a little on the technical side but not to deep. I have learned a few good things about how the stove works.

I have decided to build my stove/stand set-up to take one of my Trangia cook pots. I have two that are about the same size (1.5L & 1.75L) but one is a little deeper. I might go to a Titanium pot of the same size later.

Mike, your pictures are great.

Edited by bfornshell on 11/13/2005 20:19:39 MST.

Bill--from what I read from Mike M. over in Yahoo Groups and taken with Curt's own cutting to the bone--- would you say that the biggest weight reduction possibilities, apart from ditching the Magnesium fin housing, would be in creating a Ti stand for the burner assembly? Or can you fabricate lighter parts for the assembly, as well? Is the burner bowl a throwaway?

Edited by kdesign on 11/13/2005 22:56:51 MST.

Hi Kevin, Lets start with the Burner Bowl. The stock burner bowl weighs 25.2gr. I have made a replacement out of aluminum that weighs 6.3gr. Is it a throw away, with my 6.3gr version, not yet. Will my lightweight version do what the heavier stock item did I don't know yet. It might melt.

The Valve & Hose Assembly. I still need to take this apart and see what is inside it. then I will see how much I can trim it to reduce it's weight of 135gr. Because I am working on this stove as a primary tool for melting ice/snow at a very low temperature I don't want to degrad the ability to attach the canister to the gas line and control the stove between 20 degrees F and -20 degrees F. At this temperature you will need to do everything in gloves or mitts. More on this later. It would be nice to reduce the Valve assembly by 1/3.

How this stove looks when I am finished is still not clear. If you think of the Jet-Boil as a stove system I want my finished product to be a stove system also. That means everything built-in but with a cook pot that is put into and taken out of the stove system.

If I was making a mild season stove I could make a nice danty set of Titanium legs that weigh very little and a stove easy to use without gloves or mitts. That is not the current goal.

Bill, I have not forgotten the need to be able to use this stove in Winter----indeed, it's the only time I would ever use it unless I get into high altitude climbing again. But it sounds you feel there is still ample room to put the Xtreme on a diet.

I've not actually had the privledge to have used a stove I could really operate with my mitts. Generally speaking, I have found liners, thin or thick, adequate in the depths of Winter. It's a matter of controlled exposure.

I have heard of stoves modified for Antarctic or High Arctic use with oversized controls and fittings for use with uber mittens.

I guess I don't understand why very light Ti legs would not be adequate for the intended use----particularly if rod stock was used.

Edited by kdesign on 11/14/2005 11:16:35 MST.

Bill and Richard,
Thank you for your replies. I'm in Buffalo, NY. I'll check the local Gander Mountain for Coleman Xtreme stoves and canisters. Thanks for the info on the Coleman outlet website.
Paul

Kevin said: "I've not actually had the privledge to have used a stove I could really operate with my mitts. Generally speaking, I have found liners, thin or thick, adequate in the depths of Winter. It's a matter of controlled exposure."

You are correct, liners would have been a better word to use. I have several different kinds to include some Possum Down liners from BMW. I have been in the White Mt's when it was below "0" F. and my fingers would get cold fast outside my Mitts even with liners. My liners today are selected as carefully as I pick my mitts. Experience is a hard teacher at times.

I will know more about the Valve Assembly before the day is over. I am about to put it on the operating table.

Bill,

Keep us posted on the updates. Looks promising and hopefully the patient will survive the operation.

Rich

Edited by naturephoto1 on 11/14/2005 11:58:19 MST.

Last I checked Mcmaster was one of the more expensive options for Ti Rods.

A couple of sources:

Online Metals
Grade 2:$2-3/foot

Grade 5: $12/foot

OR

Solid Graphite Rods?

I have taken the Valve Assembly apart. Three screws and the "Heat Sink" part of the Valve comes apart/off the valve assembly. It looks just like Curt's pictures when the Heat Sink part is removed. I really thougt there would be more to it.

I thought Curt or Mike posted the weight of the Heat Sink but I can't find it. I get it as 47.6gr/1.67oz. The rest of the Valve and Hose Assembly weighs 84.3gr/2.97oz.

The first thing I am going to do to the heat sink is to remove all metal that isn't necessary to hold it together or hold the canister/Valve connection. In the cold temperatures I am making this for I think it would be nice to have something to hold onto when connecting the PowerMax canister to the valve Assembly. What you can't really see in the pictures is the black plastic parts(2) that the canister connects to. Without the heat sink those two part have nothing to hold them together. I should be able to drill or cut away half or more of the heat sink.

The second area where I might be able to reduce some weight is by making the braided stainless steel? line shorter. I will have to visit one of my local "Hot Rod" shops and see who can do something like that.

I am still not real sure I know what the Heat Sink part is doing. Trying to displace cold from the gas canister or hold heat. The fins would lead me to think they are made to displace something and not hold it.

In one of the pictures to follow you can see the new Burner Bowl I made. The cup shown (is/was) a Poached Egg Cup. I eat really well most of the time when hiking. I do have a very light weight kitchen kit when I want to go SUL.

Edited by bfornshell on 11/14/2005 20:23:26 MST.

Nice Photos, Bill!

The heat sink transfers heat to the fuel from the air. What I don't know for sure is whether this is just during startup or simmering, or maybe during warm weather operation where the fuel might vaporize just downstream of the valve.

Your bowl looks great, but I expect the stove would work just fine without any bowl at all.

What did you do to your poor pre-heat tube? That thing looks like a pretzel. :-O

Cheers,

-Mike

Edited by MikeMartin on 11/15/2005 10:35:19 MST.

Thanks Mike,

I guess what I am after is just what does the heat sink do for the stove at "0" degrees? How cold do you think the gas coming out of the canister is? Is it colder than say the outside temperature at "0" degrees or less? I guess there is a point when "0" F might seem warm. Then I have to go back to my main concern and that is the ease of doing thing when it is really cold.

I think you are right about the Burner Bowl. Since I had an extra little cup I just went ahead and made it. My fear is that the heat might melt it.

The Pre-Heat Tube, you just had to ask that question didn't you? It got a little "bent out of shape" when I was trying to take things apart the first time. I had a little trouble finding a tool that I could get into the little hole on the lower part of the burner assembly. I should be able to striaghten it up when I am done messing.

Edited by bfornshell on 11/14/2005 22:41:23 MST.

Bill writes:

>> How cold do you think the gas coming out of the canister is? Is it colder than say the outside temperature at "0" degrees or less?

The long answer:

If it's warm enough in the braided tube that the gas vaporizes before getting to the pre-heat loop, then the gas in the tube will be *much* cooler than the canister temperature due to evaporative cooling of the fuel. The fins would then serve to warm the fuel from the surrounding air and keep it vaporized. Just guessing, but I can see this happening during warm weather operation, simmering, or startup.

But, at full throttle at zero degrees, I don't expect there will be much of a pressure drop across the valve (the big drop should occur at the jet). So, (and I'm really just guessing again) I expect that at 0 deg F, the fuel won't vaporize until it gets to the pre-heat tube, and until then will remain liquid at about whatever temperature it was inside the canister. [Of course, this assumes that the pre-heat tube has not been mangled beyond all recognition.] <g>

The short answer:

My best guess is that the fins don't do squat at zero degrees once the stove is warmed up and roaring. Priming/Simmering is another story.

Edited by MikeMartin on 11/15/2005 10:30:14 MST.

Hi Mike,

Before


After



How about a longer pre-heat tube that runs all the way around the burner bowl or burner head?

Looks like your surgery has begun, Bill. I'm excited to see where this all ends up!

I agree with Mike that the burner bowl isn't necessary at all. In fact, I believe it's actually labeled a "windscreen" in the Xtremem blown-up diagram I remember seeing at some point. I'd use a windscreen regardless, so it was redundant.

I also think the fins are probably useless once the stove is running. If I remember right, the directions say to turn the stove on very low for the first 30 seconds or so, then go ahead and crank it up. This should give the pre-heat tube plenty of time to warm up - even in really cold conditions - and at that point I can't imagine the fins do anything.

I'm not sure what the temps were on Adams when I had my Xtreme "epiphany", but I had a 10 degree bag and froze my ass off. Early in the morning is when the Xtreme was doubling (at least) the output of the Whisperlite. Probably somewhere between 5 and 20 degrees.

Any lightbulbs on the stand yet??

-Curt

Bill writes:

>> How about a longer pre-heat tube that runs all the way around the burner bowl or burner head?

I don't think a longer pre-heat tube is needed. A longer tube is used with a white gas stove because the fuel vaporizes at a higher temp. A smaller preheat tube can be used with propane/butane.

BTW, that's a stunningly beautiful preheater you've got there. ;-)

Cheers,

-Mike

Edited by MikeMartin on 11/15/2005 10:28:01 MST.