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jayfin3
02-24-2012, 20:36
Hello everyone,I have made a Super Cat15317with a windscreen15315and I have a 700 mL pot with a foil cover I made15318and it all goes together like this.15316Except I can't cook anything!I put 1 oz of Heet in the Super Cat.I put 2 cups of water in the pot.I light the Super Cat and wait 30 secs, then put the pot on top, then cover it.It's 40 degrees out.First 4 times I tried it, I got a few bubbles, then my fuel ran out after about 8 min.Today I tried it in a slight drizzle, with an aluminum square underneath the Super Cat for insulation from the cold concrete, and my flame lasted for like 30+ minutes, but still did not boil the water.What am I missing here?Also, sorry all the pictures are so small..

jayfin3
02-24-2012, 20:38
Having tried 3 soda can stoves in addition, and failing at all of them, I have now come to you, whiteblaze. Help me please.

Amanita
02-24-2012, 20:39
Are you sure the alcohol is boiling when you put the pot on? I had some trouble with my supercat, but waiting until I can see that the alcohol is done heating before I put the pot on seems to be important.

jayfin3
02-24-2012, 20:42
Are you sure the alcohol is boiling when you put the pot on? I had some trouble with my supercat, but waiting until I can see that the alcohol is done heating before I put the pot on seems to be important.

Would 30 secs be enough?

blackbird04217
02-24-2012, 21:08
It seems to me that with that design, putting your pot on would require most of the flames and heat to travel up the side of the pot instead of underneath - losing a lot of it in the process. I think you'd need a pot with a larger radius. I'm not sure about the super cat, as I used soda cans with jets, but mine only took 5 to 10 seconds to prime at most. And the way I had my pot, the flames coming from the jets would hit around a "ring, in the middle of the center and outside" of the bottom.

Rusty Nail
02-24-2012, 22:20
I have the same pot and made a super cat as well with nearly the same issues.

Rocket Jones
02-24-2012, 22:27
Use a tighter windscreen. It looks like there's too much room around the perimeter of the pot.

Also, look down into the Supercat and make sure you see the fuel bubbling before putting the pot on top.

Rocket Jones
02-24-2012, 22:28
Oh yeah, and someone did some real testing and the heat rising up the sides isn't as inefficient as you'd think. Your pot is ok.

jayfin3
02-25-2012, 00:11
Thanks for your responses guys. I will try again tomorrow, tightening the windscreen and making sure the fuel bubbles. If that fails, I guess I'm gonna be getting a bigger pot.

I can't tell if the headache I am getting is from the methanol or the repeated frustrations...

jayfin3
02-25-2012, 00:12
Rusty Nail, we are like brothers.

Amanita
02-25-2012, 00:15
I found that the 30 seconds listed on Jim Wood's recommendations was not enough to get the alcohol to boil, esp if it's colder out. Fantastic guide he wrote other than that little catch though.

Storm
02-25-2012, 00:38
My stove looks exactly like yours and will bring two cups of water to a full boil with one ounce of fuel. The on difference I can see is that I don't have any holes in my windscreen. I just use some folded up aluminum foil. Not sure if that would make any difference or not.

Big Dawg
02-25-2012, 00:48
I love and have been using my SuperCat for years, and get a boil every time. One of the reasons may be because I also added kevlar wick to the outside bottom, as suggested on Jason's (http://jasonklass.webs.com/supercatwick.htm) website. I put a few drops of fuel on the wick, then fuel in the can, light,,, and presto,,, it seems to prime in no time.

Big Dawg
02-25-2012, 00:55
Use a tighter windscreen. It looks like there's too much room around the perimeter of the pot.



Agree. There should be approximately 1/4 to 1/2 inch space between the pot and the windscreen all the way around. Doing this will help to concentrate the heat on your pot better, helping you achieve boil. Plus, your windscreen only needs to go up the sides of the pot an inch or 2. Your pot size is just fine. I've used many sized pots successfully w/ the SuperCat.

Rocket Jones
02-25-2012, 01:19
I second the idea of kevlar wick around the outside. Works like a champ. Also, when the weather gets colder I carry a base for my stove made out of a cork trivet wrapped in foil. Lightweight and good insulation for under the stove and pot.

Spools
02-25-2012, 04:22
Get a pocket rocket... some folks swear by alky's but after making and trying all sorts of different designs, my giga power still works the best.

Big Dawg
02-25-2012, 06:42
Get a pocket rocket... some folks swear by alky's but after making and trying all sorts of different designs, my giga power still works the best.

My pocket rocket has been sitting in my "extra gear" tub for years. I was recently considering using it for an upcoming hike, but after thinking about the past issues regarding fuel, I decided against it. I can't tell you how many 1/4, 1/2, 1/3 full, etc, fuel canisters I have sitting in that same tub. I love that my empty alky fuel bottle is 1/2 oz instead of a 4 oz canister. I also love being able to bring exactly the fuel I need on each trip, instead of having to bring 1 canister that's 1/3 full just so I can use it up, then another full canister, which I ultimately bring half of home. I got tired of carrying fuel I never used or needed in the first place.

ken209
02-25-2012, 07:37
I use the same pot with a homemade fancee feast stove, use less than an oz of fuel for a boil.

V Eight
02-25-2012, 08:04
Jayfin3,
I just made that exact setup last week. Already had the GSI pot and my plastic lid is still useable. I made a super cat from directions I found here. When I did my first test, the weather was around 40* drizzle, 10/15 mile wind + gusts. I Put about ˝ oz denatured alcohol (room temp) in the cat and about cup of “tap” water in the pot. This all set a smooth flat rock that sits out side near my shed. It is there for only one reason, Stove testing. Anyway, it took a couple of try’s to get it to stay lit. It seemed like it took forever before I could set the pot on the cat.


2nd try, I put a primer tray from another stove under the cat. I set up the windscreen, so it would be closer to the pot. Dropped 10 or 11 drops of fuel on the tray, and 1oz of fuel in the cat. I Put the cat on the tray and lit both, the fuel in the tray & the cat. In about 20 sec’s, I had the pot setting on the cat. I had refilled the pot with about a cup of tap water. I had a good rolling boil going for about a minuet before running out of fuel. I do not use a stopwatch, so all times a guess’s


So, that worked for me. Today I am going to hike one of the local county parks. It’s not the AT, but it is a nice walk in the woods. I will be making lunch with the super cat. I am also working out the kinks of using smaller pack. Moving from a 65 liter to a 35 L. I have a couple of week long AT sections hikes, planed for later this year and I will be carrying LESS weight.

burger
02-25-2012, 09:36
My understanding is that because of their flame pattern, supercats are better with wider pots. I have an evernew 1300 mL pot, which is substantially wider than yours from the look of it, and I can boil 2 cups of water in 5 minutes with 1 ounce of fuel in almost any weather conditions. Maybe think about a wider pot.

Also, you are using yellow heet, right?

Nutbrown
02-25-2012, 09:48
Try putting 3 nails in the pot as a pot stand. Kind of looks like an upsidedown teepee. If you get the pot above the stove, it should work every time very efficiently.

Grumble
02-25-2012, 10:09
Wider pots work better with the supercats. Most of the heat will go around the pot if you use a narrow pot like a snowpeak 700ml.

Wise Old Owl
02-25-2012, 10:58
My pocket rocket has been sitting in my "extra gear" tub for years. I was recently considering using it for an upcoming hike, but after thinking about the past issues regarding fuel, I decided against it. I can't tell you how many 1/4, 1/2, 1/3 full, etc, fuel canisters I have sitting in that same tub. I love that my empty alky fuel bottle is 1/2 oz instead of a 4 oz canister. I also love being able to bring exactly the fuel I need on each trip, instead of having to bring 1 canister that's 1/3 full just so I can use it up, then another full canister, which I ultimately bring half of home. I got tired of carrying fuel I never used or needed in the first place.


Not enough power failures around to use them up?

Spokes
02-25-2012, 12:05
My goodness! There are so many cat can stove videos on YouTube showing them boiling water. If some of those guys can do it, so can you. Just make sure the flame "blooms" out the holes before you set your pot down.

Search "super cat stove" on YouTube then sit back and enjoy.

Cheers

Wise Old Owl
02-25-2012, 12:15
It seems to me that with that design, putting your pot on would require most of the flames and heat to travel up the side of the pot instead of underneath - losing a lot of it in the process. I think you'd need a pot with a larger radius. I'm not sure about the super cat, as I used soda cans with jets, but mine only took 5 to 10 seconds to prime at most. And the way I had my pot, the flames coming from the jets would hit around a "ring, in the middle of the center and outside" of the bottom.


Try putting 3 nails in the pot as a pot stand. (In the stove) * Kind of looks like an upsidedown teepee. If you get the pot above the stove, it should work every time very efficiently.


Wider pots work better with the supercats. Most of the heat will go around the pot if you use a narrow pot like a snowpeak 700ml.


My goodness! There are so many cat can stove videos on YouTube showing them boiling water. If some of those guys can do it, so can you. Just make sure the flame "blooms" out the holes before you set your pot down.

Search "super cat stove" on YouTube then sit back and enjoy.

Cheers

The wick on the side with a few drops is important - Reduce the water to 1 cup for starters and only use Heet, a wider pot and understand the limitations of not allowing enough air to move under the stove to burn - I solved the problem by jetting the flame directly under the pot and discovered I was "limiting" the air to prevent combustion... As soon as I made more air holes in the wind screen at the bottom and increased the distance between the stove and the pot to 1 1/4 inches the issues were solved. Use a metal tray underneath and exsperiment in the Kitchen with a window open if you have to.

Spools
02-25-2012, 13:00
My pocket rocket has been sitting in my "extra gear" tub for years. I was recently considering using it for an upcoming hike, but after thinking about the past issues regarding fuel, I decided against it. I can't tell you how many 1/4, 1/2, 1/3 full, etc, fuel canisters I have sitting in that same tub. I love that my empty alky fuel bottle is 1/2 oz instead of a 4 oz canister. I also love being able to bring exactly the fuel I need on each trip, instead of having to bring 1 canister that's 1/3 full just so I can use it up, then another full canister, which I ultimately bring half of home. I got tired of carrying fuel I never used or needed in the first place.

to each, his own. hot coffee in a minute, or ten. The convenience of the rocket is worth the weight to me.

Wil
02-25-2012, 13:06
It almost has to be the fuel. Your windscreen as noted is too loose, too high, and has too much ventilation, and your pot is narrower than the ideal for this stove; but all that doesn't add up to NO boil at 40F.

My stove has only a single row of holes (very slightly smaller than a standard paper punch); the windscreen extends only 2 inches up the pot and has only a single roughly 1.5 square inch air port; I hold the pot just off the flame during the initial 30 seconds or so of heatup so as to not waste that fuel. But these are all fine tuning from experience and even without any of those refinements you should be getting a boil.

rocketsocks
02-25-2012, 13:15
Hello everyone,I have made a Super Cat15317with a windscreen15315and I have a 700mL pot with a foil cover I made15318and it all goes together like this.15316Except I can't cook anything!I put 1 oz of Heat in the Super Cat.I put 2 cups of water in the pot.I light the Super Cat and wait 30 secs, then put the pot on top, then cover it.It's 40 degrees out.First 4 times I tried it, I got a few bubbles, then my fuel ran out after about 8 min.Today I tried it in a slight drizzle, with an aluminum square underneath the Super Cat for insulation from the cold concrete, and my flame lasted for like 30+ minutes, but still did not boil the water.What am I missing here?Also, sorry all the pictures are so small..If your in Boston then it's likely not the elevation.some of the tests I have seen bring water to boil at around 9 to 10 min,maybe add 1 1/4 0z.out side of that .....I don't know.good luck.

Amanita
02-25-2012, 16:04
Are you putting the stove directly on cold concrete? It could be that the heat loss through the bottom of the stove is preventing the alcohol from boiling. Try putting a foil disk under the stove, or some other form of insulation.

jayfin3
02-27-2012, 23:14
Hello everyone! I forgot to respond 2 days ago. I appreciate all the responses, they are very helpful indeed. I think my main problem was that I didn't wait for the fuel to bubble (super-dummy, right?). That, coupled with a tighter wind screen in the same conditions as my initial post, brought me to a boil in about 7 min. WOOH! yay! However, I will be thinking about a wider pot, and wick during the weeks to come as well. Thank you all!

Tinker
02-28-2012, 01:03
You can make a heat reflector (also anti-table top scorch device) from an aluminum oven pan. Works great. Cut it the same diameter as your cup or pot. Mine rests on the inside lip of my Evernew 1.3 liter pot and the pot lid holds it in place when on the move. Of course, it goes underneath the stove when in use, reflecting heat upwards and preventing fires down below.

Big Dawg
02-28-2012, 01:19
to each, his own. hot coffee in a minute, or ten. The convenience of the rocket is worth the weight to me.

"to each his own",,, HYOH,,, yadayada,,, exactly! Your "hot coffee in a minute, or ten" is not my experience. As you can imagine, I've preformed many tests w/ my supercat and pocket rocket side by side. The supercat wins most times, although it is a close race each time. The pocket rocket is definately a torch, but so is the supercat, unlike other alky models. My supercat is equiped w/ a kevlar wick on outside bottom, so priming time is nil.

Drybones
02-28-2012, 13:11
I have the same stove and boil 2-cups in 7 minutes. What caught my eye in your post is that the flame lasted 30 minutes?? The only way that could possibly happen is if the air supply is badly restricted. I cant tell much from your pictures but I'm guessing you have a problem getting enough air to burn the fuel. Try the stove without the wind screen and see what happens.

smoothsailin
02-28-2012, 13:51
http://www.ultralightdesigns.com/products/cooking/blue-mini.html
I have a stove like this one ( not the exact ) works great. 1oz boils 2 cups in 7mins