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Hello I have been making a few jam jar jets for the past few days using Heet gas line antifreeze as fuel. I made 2 jets that worked well on the day I opened the fuel and one the next day. Now all I get is a flam out the top of the jar and it stops. Would it be better to use a different fuel? Maybe just plain ethanol? I also tried to make a jet out of a tin can with the same fuel and got the same results. I would like to make my next jets out of cans because they will not break due to the heat. What size should I use and what size hole? Like this video

http://www.youtube.com/watch?v=j9y0gN8cOCo

I found out the methlated spirits is only 5% methyl alcohol and 95% ethyl could I just use plain denatured alcohol? I need any help I can get.

Thanks

"Would it be better to use a different fuel?" The Heet should make a good fuel, but should be kept in a container with a lid. I suppose the humidity in the air can collect in the fuel. Also a jar should overnight empty of fuel, to avoid the humidity from collecting.
Even with dry fuel, some days are just not low enough in humidity to run jars.

Recently tested an asparagus can that works great as a metal jar. Very difficult to empty the asparagus through a 5/16" hole.

The height is slightly more than twice the diameter. Started with a 5/16" (8mm) diameter hole and filed up to about 3/8"(9.5mm) diameter with a small round file.

Joe

Ok thanks. How long does it run for? I just kept my Heet in the bottle that it came in. I know that it will need to be cooled. I will use some very strong magnets on the can an stick them to a section of steel then put the whole thing in the bucket.

I will try to make one later on today and I will tell you how it works out.

30-40 second runs are common for the uncooled jars, but it is a comical few seconds. Cooled jars can run for several minutes.
Joe

Well last night when I tried to get my jets to run I used a steel can and a jar that I had made a jet from before and non of the worked.Just now I used the glass jar and it worked. Last night it was snowing and I was unaware that it might have an effect. Turns out it did. I gotmy jar to run for about 30 seconds before it cracked. The can because I could not get it to run the firsttime I made the hole bigger and bigger and still it did not work so I cannot test my can. I will get one today and try it out.

I like to use old V8 cans. The 2lt kind work great! And I use Methyl alcohol for mine!

Well, still did not work. I used a can that it about 6 inches tall and I drillled a 3/8 hole. All I get is a flameout and then nothing.
Where should I look for the cans I need and what size holes should I drill?

Try a 1/2 inch hole. If you can file the hole smooth so that there are no burrs in the inside, and remember to shake the can well to get some good vapour built up! Should take off right away!

OK. Does the size of the hole have to do witht he size of the can? I would think that I 12 oz can would need a different hole than a 2 liter can. But I am not the expert and thats why I need your help.

http://www.youtube.com/watch?v=6q-19r-4wpo

Do you agree with this vid? because if you do it explains why my jet is not working it goes "fwoosh" had a flame come out the top and stops just like the first one. I will have to get another can and try again.

What is the best way of the getting what ever is in the can out?

Moehawkkid wrote:OK. Does the size of the hole have to do witht he size of the can?

Definitely. Get the hole too big and the can won't run no matter what you do. Get it too small, and you'll explode the can! It HAS happened.

L Cottrill

Wow, I don't want that to happen. I will have to be carefull. What is the smallest hole I should start out with?

A 1/4" hole for a 1.5"diameterx3"tall jar. 7/16" hole for a 3"diameterx6" jar. Each jar can be a little different, depending on the shape and size. It is a good idea to practice with the small ones before moving above liter sizes.
Joe

OK,I got two cans. One 26 OZ can which I will drill a 1/2 inch hole into and a 46oz can which I have not firgured out what the hole size should be. I will test out the smaller can tonight.

Still no luck. The 26 oz can which has a length of 14.5 cm and diameter of 8.5 cm will not work with a 1/2 hole in the top I have a jam jar that is 26 oz that works quite well with a 1/2 hole. There are two reasons I think I may of had failure. 1. It was windy out and I did see the fmae dance. 2. I just opened that can that night so there might of been water in it. What happend was most of the times when I lit is was that I got a small flame to come out then a small fire starter to burn inside the can right near the top. Only a few times when I shook it up really well a bigger flamewould shootout ( once it was about a foot) then have one or two cycles. What am I doing wrong?

Thanks

The wind is a problem, the slightest wind gust across the top of a jar will often disrupt it . Also many cans have coatings on the interior. It is best to run the metal jars outside the first 10-20 attempts so the coatings can be cooked from the interior. I call this the initial bake of the jar. Try not to judge a jar until after the initial bake. Some jars will begin to run perfect, some jars just seem to never bake out.

The initial whoosh can often indicate if the hole is to large, if the sound is loud and there is a tendency to duck, the hole is probably not to large, if the whoosh is soft, then the hole is probably oversized.

The wind and water are probably the biggest problem you have now. After each good run, try to remember exactly what you did, and the type of jar used. It is best to work with 6 to 10 jars at a session to see which ones will tolerate various conditions. Try to find more jars the same as the robust runners.

I find that shaking only about three times then cleaning any fuel that may be on the top exterior surface of the lid often helps. Sometimes just giving it a count of ten after shaking will help also.

It is not so much of what you are doing wrong, but what conditions are needed for it to run. You have already run one till it cracked, which is a good sign. ha

As difficult as glass and steel jars may be, the aluminum ones are much more temperamental. Some of the aluminum ones are developing hairline cracks at the base. Not sure of it from mechanical vibration or thermal fluctuations, it reminds me of brass carburetor floats that will accumulate cracks over time.

Joe