Search found 10814 matches

by Mark
Sun Oct 19, 2003 8:09 pm
Forum: Valved pulsejet forum
Topic: Clam baker
Replies: 18
Views: 14092

I think he didn't sell his first pulsejet. The bidding stopped at $830 and I think he wants more for it. Pieter. Maybe you are correct, I followed it to the last day but not to the last minute. I was talking to Don Laird today, he drew the Dynajet drawings you sometimes see, and he said this engine...
by Mark
Sun Oct 19, 2003 2:38 pm
Forum: Rocket forum
Topic: Newspaper
Replies: 4
Views: 3957

Re: Newspaper

I lost the link to the "Rogue Movies" site with the exploding KNO3-newspaper rocket, but have a few thoughts to add on my own. First of all, Rogue Guy's rocket almost certainly burst because he sucessfully got too much surface area to burn. Newsprint propellant burns slowly, but that doesn't matter...
by Mark
Sun Oct 19, 2003 1:31 pm
Forum: Valved pulsejet forum
Topic: Clam baker
Replies: 18
Views: 14092

Re: Clam baker

There is a pulsejet you can look at for sale on eBay. Just type the word "pulsejet". I think it might be a Katydid, or about the same size. It's all of 30 pounds and produces 110 lb static thrust. Ok, all you terrorists, buy it now. Mark Ok, so you didn't bite on the first one up for sale, not to w...
by Mark
Sat Oct 18, 2003 1:06 pm
Forum: Valved pulsejet forum
Topic: Improved Tundra-Jet Valve Array
Replies: 25
Views: 16762

Re: Behavior of Reed Valves - Lessons from the DynaJet

Gentlemen - There is another approach, taken in the venerable Dynajet, that works well, at least in fairly small size valves: I believe that the retainer is NOT designed to take the reed hitting 'all at once', but rather that the valves 'roll out' onto the retainer without kinking, and with the ben...
by Mark
Sat Oct 18, 2003 2:35 am
Forum: Valved pulsejet forum
Topic: Improved Tundra-Jet Valve Array
Replies: 25
Views: 16762

You're definitely going to need a retainer (movement-limiter) of some kind or those valves will fail in a few short seconds (probably just a single-digit number). The problem is that, left to their own devices, the valves will tend to bend right at the root -- an area that will already be weakened ...
by Mark
Fri Oct 17, 2003 11:33 pm
Forum: Valveless pulsejet forum
Topic: Adjustable Jam Jar
Replies: 10
Views: 8748

Re: From howling to thrust

Mark - I also think you could do something like this, not with a true howler tube, but with a simple 'jam jar' type device like John's, but with one addition: a Logan-style tube with external fuel supply and 'choke plate' at the outside end. Imagine John's device [but with the stack solidly attache...
by Mark
Fri Oct 17, 2003 1:22 pm
Forum: Valveless pulsejet forum
Topic: Adjustable Jam Jar
Replies: 10
Views: 8748

Re: From howling to thrust

Mark, An interesting idea, but I don't think the Rijke tube is likely to turn into an engine and produce thrust. Unlike a pulsejet, it only shakes the gas column. There's nothing to push a gob of hot gas in a particular direction. In fact, the tube needs to be vertical, so that actual movement is i...
by Mark
Thu Oct 16, 2003 6:31 pm
Forum: Valveless pulsejet forum
Topic: Adjustable Jam Jar
Replies: 10
Views: 8748

Transitions

That was an interesting flame du jour there. I was toying around with a thought of using a catalyst such as the high surface area hex ceramic car catalytic converter material found in exhaust pipes. They are made up of many little tubes of platinum, paladium, or other active element coating mixtures...
by Mark
Thu Oct 16, 2003 12:48 pm
Forum: Valved pulsejet forum
Topic: More about my pulsejet
Replies: 1
Views: 3222

Re: More about my pulsejet

Good, my pulsejet is carbureted, I use normal gasoline!!!! . I modified a Dyna jet engine and my suply line is not grater then 3mm in diameter, my pulse jet starts to run but than it stops ( it run not more then 1 second, I feel it whants to go away, but!!!!),i thing there is problem whit thi carbu...
by Mark
Wed Oct 15, 2003 12:57 am
Forum: Tools and Construction
Topic: Walls
Replies: 2
Views: 2772

The black bar and a personal aside

I've had sugar-free immitation mango fruit beverage from mexico recently that used guar gum. I wouldn't call it pleasant--soon after mixing it became thick and slimy. Thixotropic, in case you didn't know, is the interesting property of a material that liquefies under shock. If you take clay and slo...
by Mark
Tue Oct 14, 2003 10:30 pm
Forum: Valved pulsejet forum
Topic: Clam baker
Replies: 18
Views: 14092

entrepreneurism

Pieter van Boven wrote:Is this a picture of the engine we are talking about?
Imagine the sound...

Pieter.
Might suffice as a lifting object to supply tundra people their supply. ha
by Mark
Tue Oct 14, 2003 12:52 pm
Forum: Valveless pulsejet forum
Topic: Proposed Design - 'Reflector Bucket' Valveless Pulsejet
Replies: 19
Views: 14475

Re: Never Hopeless

>Larry, I think this is a hopeless task. If you intend to use the rebound of compressed gas from the 'bucket', this bucket will have to be very long to accommodate all the gas spewed out of the engine intake, and to start spewing it back only after the 'normal' intake is over. If the compressed gas...
by Mark
Mon Oct 13, 2003 1:17 pm
Forum: Tools and Construction
Topic: Walls
Replies: 2
Views: 2772

Walls

After Al's topic about the silicate/steel high-temperature compound, my sister mentioned some kind of new home construction material that is somewhat see-through and used to make walls for houses. I have no idea what it is made from, but it started me wondering, if a water-glass/fiberglass based mat...
by Mark
Sat Oct 11, 2003 10:31 pm
Forum: Valved pulsejet forum
Topic: Clam baker
Replies: 18
Views: 14092

Clam baker

There is a pulsejet you can look at for sale on eBay. Just type the word "pulsejet". I think it might be a Katydid, or about the same size. It's all of 30 pounds and produces 110 lb static thrust. Ok, all you terrorists, buy it now.
Mark