Weight (Manufacturer): 16 ounces
Weight (Tested): 19.8 ounces
URL: ZZ Stove
A few years ago when I decided to try lightening up my pack load, I decided that my Peak 1 Multifuel was a big target for the hit list. It has a 1.5 pound base weight with the spare fuel bottle, and then you need to carry fuel, sometimes up to another 1.5 pounds. So I started looking at MSR Whisperlites, Primus Varifuels, and the Zip Stove.
I eventually built my Cat Stove which turns out to be a great choice, but I've always wondered about the claimed performance of the Zip Stove and the possibility of my passing a great opportunity for weight savings with outstanding performance.
The claims are 1 pound weight for the stove, operates off one AA battery, burned anything combustible - including wet wood, and rugged construction. So now you have a stove that you don't need to carry fuel for (obvious weight savings), can hardly break, and weighs less than many gas stoves. I even found sites that had instructions to reduce the zip stove weight.
Part of my problem with accepting all this was the fact that the weight on different pages wasn't clear, the manufacturer's web site wasn't very informative, and I couldn't find a store to actually see one. So it was a great unknown as to whether it was worth trying.
Recently I became acquainted with another backpacker with a trail name of Hog On Ice, who owned one and wanted my opinion on them. I told him how I really didn't have one since I had never used one, but I was interested in the idea. He offered to let me try one, and promptly mailed it to me. So here I am - playing with a new stove for the comparison tests.
My first impression when I opened the package was - gee this thing is big and heavy! Actually, it isn't that heavy, but after months of using alcohol and Esbit stoves, it sure did seem like it. So, I put it on the scale - 19.8 ounces without a battery, if you use a AA lithium battery, then 20.3 should be the carried weight. It packs down by removing the base and putting it inside the burn chamber of the stove. the stove is about the right size to fit inside a 1.5L pot. If you use a pot that large, then you can pack it in there to reduce bulk.
The burn chamber has an outer wall made of metal and an inner chamber wall of the same material. Along the inside of this inner chamber are 16 air holes. At the bottom of the chamber is a intake hole. The fan, which is a part of the base, blows up the bottom hole, circulating the air between the outer wall and the inner chamber then blowing out thru the air holes of the inner chamber. This causes the fire in the inner chamber to burn like a forge. the fan is the same type used in tape recorders - so it will operate for hours without fail. It runs off 1.5 volts from the AA battery which is housed inside a stamped metal box connected by the power cord, and is controlled by a three way switch for off - low - high operation of the fan. The pot sits above the burn chamber on four pot holder stands which gives room to feed small twigs and air opening for the fire to breath.
So after playing with it and figuring out the basics of operation I tried it out. For my first test I got a couple of empty grit packages - my standard fire starter paper because I have 2 of them emptied at the beginning of the day, and they weigh hardly anything. for fuel I just went to the park behind my house and got a couple of small dead fall branches. I tried starting my fire as I usually start a small cooking fire using one piece of paper and some small twigs. It was harder than I thought it would be with limited space to get going with, but eventually I got it going with a little more paper than I normally have to use.
Now I used my titanium pot with 2 cups cold water. At 4:00 the water had bubbles from boil starting, and at 5:00 a roiling boil was achieved - not bad. Fuel was sometimes hard to feed, but after a little practice it wasn't hard. I did need to have fuel ready and feed it in as the stove was cooking. Simmering was as easy as turning the fan down or off. The fan does seem to have problems, it kept changing speeds on it's own. The battery was new, so I'll have to investigate the cause of that.
I haven't tried to burn any wet wood, but I look forward to trying that test, especially under field conditions.
So, my initial concerns and thoughts:
1. Is there a problem with the fan motor?
2. Is there a way to redesign the base? It doesn't seem like a good design.
3. Is there a possible way to make a smaller ultralight version?
4. With the difficulty to get dry wood going, will wet wood be a huge pain to use?
More reports to follow.
Just a small follow up. After playing with the stove and my own light weight design I have answered some of my own questions:
1. Problem with the fan motor? No, it turns out the problem was poor contact in the fan switch. This was solved by rotating the battery while still inside the housing.
2. Redesigning the base? There are some web sites for people that have modified their own zip stoves. John O has an 8 ounce stove with re designed base. The most modified for stability base would be by Peter, although his comes in 3 ounces heavier.
3. Make a lighter version? Yes, I did it. Do I recommend making one? No. The problems are durability of the burn chamber, fan output, and performance. To make a lighter zip, I had to make it smaller. Making it smaller meant a smaller burn chamber, which results in problems starting and maintaining fires. Except for making a shorter chamber, there isn't a good way to make a smaller chamber. If you want to try, I made some plans and you can get a fan here. If you want to make a durable stove, then your best bet is to modify an original model like in the above links for John O and Peter.
4. Dry and wet wood? Learning to start a fire in the Zip stove takes some practice but can be done in my experience with the standard day's food trash, thus saving you some carry weight. Getting wet wood to start takes the same strategies as starting a camp fire with wet wood. Using some dry tinder, some sort of fire starter, etc. Once you get a fire going, wet wood does burn well, it just takes longer to get a fire going good.
I used the Zip stove early this month on a one week Army field training exercise. I used it mostly to heat water for coffee, ramen, and occasional shaving water. Fortunately on this trip I had two experienced backpackers with me. I also got the both of them to give me some comments about the Zip stove.
Fuel availability would have to be the number one on this trip. I never had to pour or store fuel. Fuel was literally laying around for me to pick up. Even after a hard rain I could still get a great bed of coals to cook with in this stove.
This leads me to another pro - heating source. Since most stoves use precious fuel, we never consider them a source for personal warmth other than getting our fingers and face warm while cooking. Since fuel isn't a problem, and the stove can make huge jets of flames if you want it too, this stove could be used in camp for warmth and to help get a camp fire going from wet wood. Such a pro would be great in the early wet/cold spring.
Weigh can be considered a pro, but not a big one (read below). When you comparing the weight of a Zip stove to a MSR or Peak1 with fuel bottle, the Zip stove is lighter than them even without fuel. BUT Primus and MSR are both coming out with fuel stoves that will be lighter even with fuel.
(added 23 Sep 01) Other Pros that I didn't think of at the time of the report are:
1. You could eliminate the need for a filter system by using the ZIP stove to boil all your water. Since you don't need to worry about fuel, you could boil LOTS of water for no additional carried weight. Depending on your current filter/treatment system, this could save you lots of weight, but not necessarily time.
2. The smoke helps keep the bugs away. OK, maybe you prefer bug juice to smoke smell, but hey, it could be a pro.
3. Ashes produced make excellent pot cleanser - gotta use everything to your advantage.
4. You could say that the wood smoke smell makes a more pleasant odor than hiker BO, but it is a stretch.
Weigh would be my number one. Even though you could cook forever on one, most of us wouldn't anyway. At 15.7 ounces, a canister stove user could have a 4.1 ounce lower starting weight and be able to cook one meal a day for 30 days! And, the canister stove user would have a stove/fuel weight that got lighter every day. Using my Cat stove system, I could start out with 22 ounces of fuel - enough to cook three meals a day for 30 days and still have a lower starting weight than a zip stove! Since most hikers only hike for up to a week between re-supply, you could cook 12 meals a day for the same weight between re-supply stops!
Another con was the stability - because of the support design, there were a few times I almost lost my dinner. I would recommend Peter's support system. You will also need to keep your pot covered, ash blows everywhere, I got some in my ramen. The stove also leaves soot all over the pot. I don't worry too much about shinny pots, but the soot was to the point I needed to clean pots before storing.
The stove claims to boil water in 4 minutes, I would agree that if you first establish a bed of coals in the stove, you can do this, but if you think you can light this stove and have boiling water four minutes later you'll be disappointed. It was more like 10 to 15 minutes depending on how dry the wood was.
If I was going to own one, I would start by making the Peter's support and John O's burn chamber modifications. That would probably get you a base weight of 9 ounces. Unfortunately I still think this would be too heavy for true ultra light backpacking. To make that realm, I would estimate a base weight of about 7.7 ounces or lower (with battery) would be needed - compared to a base retail weight of 19.8 (without battery BTW) means that the ZIP stove has a long way to go for meeting the needs of ultralight backpackers.
When would I want one? If I needed to cook for a large group, especially if hiking in wet/cold conditions, then I could see a definite benefit to using a Zip stove instead of an alcohol, gas, or canister stove.
Also, a big thanks again to Hog On Ice for loaning me this stove for testing!