View Full Version : Building a 20 lb Thrust Pulse Jet Engine with Argus Valves

12-25-2010, 04:38 PM
This is the project I have been working on for the past few weeks. It is a 20 lbs thrust pulse jet engine with 32 real Argus type valves. This it a small version of the German V1 buzz bomb engine. I had to build my own test equipment so I could test valves to make sure they would work. I had to make several mill and drill fixtures too. Here is the finished engine.

The first pictures is a reed valve cages.

1. http://i43.photobucket.com/albums/e358/gary350/PJ-02.jpg

The second picture is a reed valve cage in the mill fixture.

2. http://i43.photobucket.com/albums/e358/gary350/PJ-03.jpg

The third picture shows the reed valve cage after it was milled.

3. http://i43.photobucket.com/albums/e358/gary350/PJ-04.jpg

The forth picture shows all the finished cages.

4. http://i43.photobucket.com/albums/e358/gary350/PJ-05.jpg

The fifth picture shows all the reed valves.

5. http://i43.photobucket.com/albums/e358/gary350/PJ-07.jpg

This photo is the reed valve assemble on the engine.

6. http://i43.photobucket.com/albums/e358/gary350/PJ-13.jpg

This photo is the pulse jet engine.

7. http://i43.photobucket.com/albums/e358/gary350/PJ-14.jpg

Video of the pulse jet engine running. Propane tank is 40 degrees F too cold to produce enough fuel to run the engine at full throttle. I have run this engine 3 times about 2 minutes each time the reed valves show no signs of getting hot and no reed valve damage either.


This is a video of a German V1 flying bomb.


12-25-2010, 05:04 PM
What's the combustion chamber/tailpipe made of? Looks like you need Hastelloy X or waspalloy for much life. The burn looks pretty clean. How is the fuel regulated?

12-25-2010, 05:55 PM
Thats really cool.
Are you going to build a V1 to go with it. That would be so cool to watch fly.
Thanks for all the pictures.

12-25-2010, 05:57 PM
Awsome, I loved that shot right into the reed valves and seeing the actual internal combustion, that was so cool.

Nice array of reed valves too. I guess its the 'shielding' of the reed valves by the cage that helps keep them cool?

12-25-2010, 06:05 PM
Very cool Gary!

Are you working according to a set of plans, or are you scaling the original V1 design?

12-25-2010, 06:34 PM
How loud is it?

12-25-2010, 06:41 PM
Very nice Gary!
I have always had a desire to to build a valveless pulse jet engine (http://www.youtube.com/watch?v=EEHw9lInIfg)because of it's less complex nature, but I have to admit I do like your effort very much.

What type of material did you use for the reed valves?

Hey it's a great way to warm up the shop...as long as the neighbors don't complain about the noise.:D

Al Messer
12-25-2010, 06:50 PM
Super job!! Please keep the photos coming.

12-25-2010, 06:51 PM
I have complete plans for the "LoudMouth" free piston jet engine. You can download them from my server. They were available free.


It produces 80 hp from 20 pounds of engine. It is loud enough to kill large animals over the horizon... :eek:

12-25-2010, 07:44 PM
I will try to answer everyones questions all in 1 post.

The tail pipe is muffler pipe I bought from a local muffler shop. The combustion chamber is a piece of EMT electrical conduit. The cone is mild steel. The valve cage is CRS. The reed valves are .010" blue spring steel. The fuel is regulated with a pressure regulator. All pulse jet engines start easy at low thrust then I increase the regulator pressure to full throttle. The design of the engine makes the fuel/air mixture automatic. When the engine fires it blows all the power out the exhaust pipe. The kenetic energy acts like a piston traveling down the tail pipe. About half way down the tail pipe interenal pressure drops to zero the rest of the way down the tail pipe it suck a vacuum inside the engine so it automatically sucks in more air and fuel. The combustion chamber pressure each time the engine fires stops the flow of fuel for a split second. The ratio of air intake cross sectional area to tail pipe cross sectional area is what determines the fuel to air mixture ratio. I intent to build 3 fuel systems just like the German V1 engine when I get more time. At the moment I am still doing research on the small engines. The German V1 had a start fuel system, a run fuel system, and a ram air fuel system. The V1 was started at low throttle then it was throttled to full power when it was launched from the ramp. As the engine picked up speed ram air made the engine run lean so a 3rd fuel system detected ram air and gave the engine more fuel. There was also a fuel regulator that detected elevation as the engine climbed to an altitude of 2000 ft the fuel regulator pressure was decreased for thin air.

I am not planning to build a V1 I am only interested in the engine. I do plan to build a full size German V1 engine some day.

There are 2 things that protect the reed valves that are designed into the engine. The tail pipe is made longer than it needs to be this produces more kenetic energy that sucks the flame away from the valves. There is also a shield device inside the engine that helps to protect the valves. The number one thing that protects the valves is they only allowed to open a certain amount this keeps them from beating themself to death. The length and width and metal thickness also has a lot to do with valve life. I have several other engines I have run them for several hours each with no damage to the valves at all. The valves show no signs of getting hot.

I am not working from any plans. I design my own engines. I have the original 8 years of German V1 research data transulated to english. I also have 3 research papers from 3 different college engineering students that did research on pulse jet engine. I have been doing my own research and I have come up with formulas to design and build pulse jet engines any thrust I like. I have learned a lot from experementing I have a much better design that the Germans the engine run for several hours and are pretty much maintenance free.

I built 1 valveless pulse jet engine. It is basically a noice maker that burns a lot of fuel. Valveless engine produce some thrust but not much compaired to valved engines.

Al Messer
As soon as I get a fuel system built for this engine and get it on the test stand to check the actually thrust of the engine I will have more videos.

I have the plans for the loud mouth engine too. It looks very interesting but I don't think I will build one. I am having too much fun with pulse jets and I have several more larger ones to build before I move on to a different project. I only work on this project during the winter when I become a prison in the work shop because of bad weather. During the summer I camp, hike, bicycle, etc.

12-25-2010, 08:06 PM
Ausgezeichnete Arbeit! Heute Home Shop Machinist, morgen die ganze Welt!:D

Seriously,though,nice job! Of course the next step is to slap it on a gokart frame:)

12-25-2010, 08:13 PM
The scene: Two years ago at the conclusion of his court mandated Anger Management classes...

Counselor: Well Gary, you've been a model student, and I think these classes will be of great benefit to you.

Gary: Thanks, miss Dugenswart

Counselor: Just one parting thought, I'd like to see you take up a hobby. You mentioned your machining skills and I think that may be a great start. I'd like to see you pursue that, it'll give you an opportunity to express your creativity, To build things and be constructive. Plus it'll distract you from your annoying neighbors that got you into this pickle to begin with.

Gary: Hmmmmm......

Ian B
12-26-2010, 04:47 AM

Did you consider using a conventional, electric drive power feed for your mill's table, instead of a jet engine? :-)

Seriously, very nice piece of work - I'd only seen the petal type valves before. Those are much more like the ones found in a 2 stroke engine, and look like they'll last much longer.


12-26-2010, 01:02 PM
I am not planning to build a V1 I am only interested in the engine. I do plan to build a full size German V1 engine some day.

I have several other engines I have run them for several hours each with no damage to the valves at all. The valves show no signs of getting hot.

l I have a much better design that the Germans the engine run for several hours and are pretty much maintenance free.


The German engines were also maintenance free. In fact I have heard from reliable sources that not one ever returned to the shop for repairs.

J Tiers
12-26-2010, 02:43 PM
it was fun, fun, fun, 'till Homeland security came to call????

Confiscating shop, computers, etc. Good luck getting it back, after the free trip to Guantanamo.

12-26-2010, 02:52 PM
Very cool!

If you need some help imagining things to do with your engines, here is one inspiration: :D http://www.youtube.com/watch?v=7zgc1yqICII

11-30-2012, 11:48 AM
hi Gary, thank's for showing this super job, I know this is a reply to an old post, but I hope you will reply me, I admire your insistence in completing the whole engine, I've tried to make a similar job too, but I have few problems with the valve: how can you determine its length and width? why 32 valves? I've read that the angle is 45 deg. for the valves, but I've seen some of the Argus plans over the internet it seems about 20 deg. and how can you test it to ensure it will work?