1946 RC Pulse Jet Engine - WILL IT RUN? Let's find out!
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- Опубліковано 2 сер 2024
- Thank you to everyone with the positive comments and great advice. I appreciate it! I'm currently working on getting continuous spark and forced air into it for start up. I'll be making a follow-up episode when I get it burning fuel as it was designed! So stay tuned and subscribe!
Will this antique RC Pulse Jet from 1946 run again? Any suggestions and comments are always welcome and encouraged. An amazing post war antique toy jet made in the USA.
My friend Luke loaned this to me to see if it will. Thanks Luke! - Авто та транспорт
Thank you to everyone with the positive comments and great advice. I appreciate it! I'm currently working on getting continuous spark and forced air into it for start up. I'll be making a follow-up episode when I get it burning fuel as it was designed! So stay tuned and subscribe!
They never had "continous ignition". They ran them up to self sustaining temperature for the fuel. Then launch...
More than a decade ago there was a continuous ignitor made and sold for the pulsejet by someone on eBay. For high pressure tire valve a 20 gallon tank would be good if you have space and access to a compressor to fill it. 12V Emergency tire compressor might work directly, quality and performance of those varies wildly. Good = $$$$
I and all keep forgetting to mention the obvious, Ear protection needed by all nearby. Either the headphone type seen at gun ranges or earplugs or both.
Too bad there wasn't some way to disconnect that giant discharge tube attached to it.
That kind of length must create "a little" backpressure. I might also question the combustibility of the propellant in use.
I suspect that today's fuels may not be exactly what it was designed for as opposed to 70yrs ago or whenever it was made.
Check your read valves. they are a wear out.
Just looked at a video with an RC He-162 with a pulsejet(and boy was that FAST!), and to get it started, they used TWO leafblowers, one up front and one at the rear. So, the engine probably needs proper "airflow" to run well, so just putting in air at the front may not be enough to get it started(or at least, much harder to get it started).
I've run these before. The igniter should be driven by an oscillator to continually buzz. You should have much more air to string those little pops together. This will allow it to warm up and help it auto ignite. If memory serves we used alcohol but you have the manual. The fuel matters as jetting volume has to be in range for the fuel. You should have a much stronger clamp as it will be aggressive at full power. I want to see it glowing yellow and howling - I hope you will make a follow on video.
Long story short, it’s a pulse jet just fyi
Those tips make a lot of sense. Would be cool to see a follow up with that thing running at full (safely mounted of course). Nice video!
Friend of mine used a scuba diving tank which has a lot more volume for it to warm up!
Big thanks Ken! I found a step up transformer online that creates a continuous spark which I'll be testing as soon as I get it. Also, I'm using 87 octane unleaded gasoline which contains 10% ethanol. The original manual says to use "unleaded gasoline" and a tire pump to start it. If the I still can't get the gasoline to ignite, I'll get some Denatured alcohol. I'll also use my leaf blower to inject more volume thru the venturi chamber. When I use the tire pump, I can see the gas from the tank go up thru the clear tubing up to the metering valve so I know it's temporarily getting fuel. I'll keep everyone posted!
@FlatheadTerry : get some coleman lantern gas. That's the stuff you need.
I have a couple of old pulse jets that I run very occasionally. First I would say you need a trembler coil to run the spark plug so you get a continuous spark. Next you need enough air going into the engine to open the flap valves and to draw fuel into the engine. A bit of clear silicone tubing as fuel line would show the fuel being drawn into the engine. For starting mine I squirt neat fuel into the engine nose while the air is running then turn on the trembler coil. There should be one or two pops then the engine is running. Often a belch of flame out of the exhaust on starting. Your engine sounded far too lean for starting. If it is running properly the exhaust tube gets red hot very quickly. There is quite a technique to learn to start them and each engine is different. Some people have a lot of success starting them with the leaf blower.
I knew an old guy, whose whole street in the 1940s ( from memory, he was talking about half a dozen or so school-boy neighbours ) used to hand build and "race" these motors. No plane, just the roaring, blazing, red-hot-glowing jet, and I think he said you needed a fuel tank ahead of the air-intake . . . I can't actually remember the DETAIL about how the design of the fuel tank *_was all important.-_* but from memory of what he told me, the fuel supply was the source of success or failure.
And you had to pre-heat the motor with a flame, and then you had to get the motor up to a certain speed before it would run "true".
They pre-heated with a blow-torch made with a Primus pressure tank, like people used to use to strip paint off things once, or, in fact, used to pre-heat the really top flight racing motorbike engines with.
And they got the engine up to speed and "flew" it by spinning it in a circle at the end of 15 feet of piano wire on a pole.
:)
Once it was running, it would just accelerate, it fed itself the fuel at a set rate, but the higher temperature and the forced draft made it more and more and more efficient in its fuel use, so it would accelerate, and pull harder against the pole.
On the tip of the pole, was a swivel, and the trick was once it was roaring, you held the pole above your head straight up, and tried to keep the pole still and vertical . . .
Everyone who was there for the testing was either crouched down at the feet of the guy "flying" his model, or watching while laying on the "safe" side of a wall or ditch.
It was "safe" nowhere near one of them, of course, because when they went wrong, their gathered up anything or any one in the way of their piano wire, and then the jet wound round faster and faster until it had no more wire/broke free and flew away at 400 MPH. Just like one of Wile Coyote's inventions, as I was happily told.
How did they learn how to do this, you may ask. The jet guys were experimenting this way for years before the V1 rockets, and published papers telling the ins and outs. And boys were more capable, in my dads childhood.
I was surprised that the plug was a Champion V2. I'd have thought it would take a V1! (I'll just leave that there for the WWII geeks to appreciate.)
The V2 was actually called the A4. Real ww2 history buffs know this 😉
@@Ben-z8g That's like insisting that the Vought Corsair was _actually_ called the F4U. Both names were used.
@AcmeRacing sir, you're talking werner von brauns granson he named it the a4 Hitler renamed it. 👍
@@Ben-z8g Right ... the Nazis financed development, manufactured it (with slave labor) and deployed it as a weapon, and called it the V2. The Nazis also financed development of the Fi 103 pulse-jet cruise missile and called it the V1. Your grandpa worked for some terrible people before he surrendered to the U.S. Army and came to work for NACA/NASA. (Meanwhile, my comment doesn't work at all if I call them the A4 and the Fi 103.)
I have a pair of these. It’s been decades since I fired them up, but I’ll tell you this: have your ear protection ready and a fire extinguisher standing by. Seriously very loud and the exhaust pipe will get red hot! Actually make that two fire extinguishers and a water hose (don’t ask, lol).
You’ll need a longer burst of air initially, and we also used a hand crank igniter pulsing ~20hz.
To say these things are dangerous is an understatement. You’ll have everyone within a mile wondering wtf is going on… again, don’t ask.
Good luck.
I would request you scan the literature and make them available for all.
@@steen8156 great tips! Thanks!
@@FlatheadTerry I also forgot to mention that I’d strongly suggest you secure it better than in your video. A single cheap hose clamp after getting red hot and expanding…. If that pulse jet gets away… well, I’ll leave it to your imagination.
Good luck!
@steen8156 Great advice! Will do! Thank you!
Right before he died in 1965, my father bought an OS pulse jet for me. All these years & three countries later I still have it & have never fired it but tried to a swillion years ago.
It's a big task to make use of these, and then not of such great interest. A lot of information is now available on the Internet. PDF of old magazines and magazine articles of hobby. Control line operation requires good physical fitness and a facility to fly them at. I'm not finding any plans for tethered car or boat use. Pulse Jets are not allowed for those speed competitions. Hearing protection is important for all nearby when these are working. Plenty of giggles online, see Robert Maddox, of pulse jet bicycles for sale of I think Arizona and Bruce Simpson of Xjet of New Zealand who flies them RC.
You need a lot more air flowing than you're giving it.
I built and flew a control line model aircraft powered by a pulse jet in England back around 1960. It was basically a pulse jet motor with stubby aluminum wings clamped to the tube, and a bell crank linked to an elevator mounted on the rear. We flew it in a circle on 50' steel wires from a U handle held by the 'pilot'. They may have been shorter. Maybe 30'. It was long time ago and my memory is not that good.
We would get the air and fuel mixture flowing through the engine and then light it from the tail pipe with a paraffin fueled pump up painters blow torch normally used to remove old paint off old buildings. Our pulse jet had no electrical igniter. We would use old car inner tubes that we would inflate at a gas station on our way to the school yard where we flew on Sunday mornings. We'd usually have a few that we carried around our bodies as we rode our bicycles to the High School property.
The pulse jet was loud! Very loud!!! And the one I flew was very fast. Once running the small fuel tank was good for about 3-5 minutes elapsed time, but often less as it could waste some fuel getting it lit. But once it was buzzing it was hard to stop it flying. The tail pipe would get red hot and eventually one day it got so hot it melted the clamps holding the wings to the pipe and it launch off like a buzz bomb into the distant school playing fields. After that I sold it to a US service man from a nearby US base and never saw it again. With no regrets. It was a bloody dangerous contraption.
Awesome story. Thanks for sharing.
They can be tricky. You need a continous spark . Oh and some ear protection as they are very loud.
Polish it up and display it. It's very nice
Thanks for the tips Don! Appreciate it!
The flapper valve looks to not be closing causing a loss of pressure from the ignition?
I use to hear those motors in the park near my house over 70 years ago. They were very loud and as you noticed , hard to start. In the park they flew many “U” control air planes. The jets had a wing but the propulsion gave it the flight. They flew in a circle very fast compared to the piston powered aircraft.
Wow! Would like to have seen those fly! Cool stuff!
I worked for a Harley dealer, built his shop in 1946. He had an old pulse jet hanging up in the shop, very similar looking, but several times larger. He told me it was incredibly loud when fired up, so it'd been years since he ran it. He'd been an aircraft mechanic in the Navy in WW II, served on USS Hornet (CV-8).
Damn! Would love to see it!
@@FlatheadTerry Yeah, old "Limey" and Myrtle had the Harley dealership over 55 yrs. Had to close up the old shop, and move to a big new one, a few years back. Then they finally sold the franchise and retired. Passed on now, but family still owns the old shop. Their oldest son works on his racing motors there. The pulse jet was still hanging up over the work bench last time I stopped by. Hollingsworth H-D, St Augustine, Florida. US 1 North.
There's a guy here on YT that does nothing but Pulse jets, give it a search and see if watching his work will help or, perhaps just contact him?
Not near enough air pressure and flow! I had one as a kid. I found I needed at least 80psi@20CFM's of air to ignite it. I had a little, 2-gal air compressor set at 90psi I think... The thing is LOUD! Oh, I would suggest covering that wood in loosely wrapped aluminum foil. The heat from that tube will make short work out of that plank! Pinch off the fuel line to kill the engine. I used an old Model T ignition coil for the spark. There are other continuous spark solutions available.
Excellent info Craig! Thank you! I definitely need to increase CFM and get continuous spark. I like your idea of the Model T coil and aluminum foil once I get it to "glow". I'm on it!
@@FlatheadTerry The motor, although far from practical, is a kick in the ass! It would be cool to build a scale V-1 rocket and see it fly. That would take a tin maker to build the fuselage. I'm glad I could be of help and look forward to seeing that thing light off!
Superb and interesting content. Well worth the effort. People who don`t think so are perhaps not appreciating the historical significance of the engine. We are so hardened to engineering efficiency these days. Also, what a thing of beauty it is. Nice video. Thank you for all that trouble,
@@thekarmafarmer608 Thank you for the kind words! Appreciate it!
Londoners can sleep tight tonight, way cool gizmo I’m confident that you will get it going!
The fact that you have one of these is success in itself.
Great comment Mohawkdriver! Appreciate that!
You need a continuous spark to get it started. That way you just have to pump the air in. Once it heats up enough, the chamber is hot enough to ignite the fuel and you don't need the spark.
Need a glow plug
@@bigc1903 Got it. Thanks!
I remember something similar from the 1960's called a Red Head . They were flown on a wire control line. They were very loud and quickly became a red hot fire hazard. No doubt, leading to countless fires and burned hands(law suits). Thanks for sharing.
About 5 years ago approximately, a company called Hobbyking made a remodel of these and called it the Hobbyking redhead... came in retro packaging with spare parts, I bought one a few years back and it ran well... blimmen noisy bugger!! currently in storage somewhere. I plan to strap it on a delta wing one day :)
Interesting that most of the principles of pulse jet , and of 2-stroke motorcycles engines very similar with respect to one-way intake, reed valves / shutter valves and tune length exhaust. Also that the East German 2-stroke race engineer were winning races, unti they defected with the technology to Suzuki in 1950s/ 1960s. Then Suzuki became predominant GP winner. ;)
A lot of trained-at-public-expense engineers flee socialist countries when it's time to pay back.
5:35 loved that hip hop beat 🤣
Back in the 60s I had a Dyna-Jet, and it was recommended to run it on ‘white gas’. available from Amaco? Kinda fussy, but they did run, and sounded like all the demons in hell were screaming! I loved it!
That was really interesting, thanks for sharing. I suspect the fuel/mix was the issue, but yes it worked!
The last time I used a Dyna Jet was in High School back in 1969. I think it was a larger version to what you have. I remember you had to pulse the air intake and spark plug just right, to get it to work. One of the models we ha use a glow plug and it was just the air you had to get right. We did eventually get them to run and one managed 21 pounds thrust on a static stand.
@@steamboatmodel Wow! Cool stuff. Thanks!
That's ridiculously COOL!! Brilliant video.
Attach a stun gun rather than a BBQ lighter
Try heating the jet pipe to red-heat so the cycle self sustains.
I think the pulse jet would work better if it had a "flame holder", I would start with a small hollow cone of stainless steel with SS mesh over the cone's base. The idea is that the mesh would hold the flame in a stagnant area between combustion cycles. Cheers
small sparkplugs for small engines and model engines are still made.
Thanks for the info!
Unbelievable they already had toy jet engines in 1946!
@@deathdoor I'm amazed too!
"Fieseler Fi 103 (V1 Flying Bomb)" and "Argus As 014 " have entered the chat ! JA!
The cool factor of the engine far exceeds any alleged shortcomings. I loved this.
Totally agree Dan!!! Thanks for the comment!
give it a good sandblast, then set up a 555 circuit to continually pulse the ignitor, and use the air compressor, these things need spark and air to line up, and it usually takes a few sparks once it starts to stabilize and self sustain, so having a monostable vibrator circuit running the coil will make it easier to start.
those reed valves wear out really quickly and basically if you can see any daylight thru them they're done. They should just be spring steel so it shouldn't be hard to fabricate some new ones.
Pressurised fuel so it forms a spray..
or feed in a little LP for initial ignition/heat as a "starter mix"?
mix with pressurised air...
try an electric leaf blower for continuous volume or an old fashioned (or garage) vacuum with the hose plugged in to the exhaust of the vacuum cleaner..
then the mix hits the continuously running spark plug...
when the chamber gets hot it will run without the spark plug needing to ignite it.
success!!
I had success with a more continuous air draught, aimed at the main inlet after the initial ignition occured. I had a Dynajet. Darned noisy ! - I sold it .... But wish I'd kept it.
Thanks! I'm working on both of those issues for PART 2!
A couple of ways of getting it to run spring to mind.
Firstly, you probably don't want unleaded, you're better off with kerosene / coleman stove gas.
Secondly, you might want to look at a better spark. Either a buzz box (Model T style) or some other way of getting a continuous spark for starting.
The pump method works pretty well, it was the stock way to fire up most commercially made pulsejets. But there is another way...
Take a spray bottle with some methanol in it (Heet, I believe, is the easiest branded product to get in 'Murica). A couple of squirts up the tailpipe, and fire it off with the spark plug or even simply by lighting the tailpipe with a lighter. With no fuel line attached, that should get it to buzz for a couple of seconds. With the fuel line attached and primed, that should kick it off with very little fuss. You'll still need to mess with the metering, though.
Great info! Thank you! I'm on it!
Same thoughts on fuel, for the ignitor you can get AA powered ignitors for gas hobs/portable heater etc that give a continuous park when you hold the button in, so you aren't so dependent on timing and will keep it lit until its up to temperature, only a few dollars from amazon.
Easily got my thumbs up! Very interesting to follow along. I was born in the early 60's and never seen anything like that pulse jet engine.
You will need a buzz coil to make it run. Something along the lines of a model A coil.
Need constant ignition, large compressor and maybe a leaf blower to start, asjust mixture, dope with starting fluid, itll fire up
Great info Markrix! Thank you! I will take your advice and continue the quest!
Adding a dash of Nitro fuel will help get it going. A cracker box from a water heater for the ignition. And run a computer fan in front of the inlet until it's all warmed up.
For a almost hundred year of piece of technology ( who's components have long out live their intended duration ) it is still impresive you manage to make it show some flames
For first time I would try glow plug to sort fuel mixture and continuous run ,also todays "petrol" is not the same as 1946 one resulting in different air -fuel ratio , combustion temperature ,shock wave characteristic .
Perseverance is a virtue.
Wow Terry!!! That’s the most amazing flathead you have ever featured on your channel to date! You sure do come up with some pretty cool and amazing things. I never heard of anything like this. Thanks for sharing!
Ha! You bet Wayne! As you can see, I really can't step away from anything vintage to a fault!
I've never worked on one of these,but I would think you would have to pressurize the tank. Did you have a good gasket on it? You would probably have to force the fuel up into the motor to get it to start along with a bunch of air too. This probably would have been in a model airplane flying about 40 MPH. Just some thoughts.
Terry,I just tried to link you to another youtubers channel as he recently showed how he started up a reed valve pulse jet. If you do a youtube search for Johnny Q90 and Pulse Jet you should find his recent video and maybe get some useful info/ideas from what you see.
Decades ago I purchased the plans for a pulse jet motor, a jet in a coffee can was the by-line. Noise is their big problem, that's why German V2's were called buzz bombs, they could be heard coming for ages.
V1!
The V1 was a pulse jet but the V2 was a rocket powered ballistic missile used on longer range targets.
@@howardosborne8647 Your right, I only realised my mistake much later getting my V1's & V2's confuddled. Cheers.
When toys were fun and educational. With all the technology today and the miniaturization of everything toys suck. And they teach kids how to be just evil. Bring back good toys!
Did anyone else laugh at he noise from attempt #12?
@rafezetter8003 Oh yes!
At SAAB, they tested an U/C (line control) model of the Draken Airplane. I was heard all over the town in the flight.
It still exists in the museum.
That's cool! I looked up the Draken and that's an awesome aircraft.
@CanuckBeaver
0 seconds ago
Great idea, and the good advice in comments. I was born in 1942, when Mitchell bombed Tokyo. In the sandbox I played "bombs over Tokyo" with out knowing what it meant. My father had a basement full of surplus tools, like metal and wood lathe with instruction manuals dated 1937. No TV until about 1949. I had electic trains, mechano sets, crystal radios, and so on. Our record player was a wind up 78 rpm with the horn. Our refrigerator was an icebox. A monstrous ice cream cone cost 5 cents.
Every kid with any ambition was a Saturday mechanic on some hobby. The men were from farms and factories, which made great soldiers who could haywire anything.
I see the same practical skills and innovation in Ukraine today, and in Russia with thier turtle tanks. Anyone in rural areas knew how to hunt and survive.
I looked at a bunch of comments but not one mentioned the fact that you need a high air flow to light that puppy up. That will run if you do
you need cfm not pressure, so the blow output of a vacuum or leafblower would be best, compressor can work, 0% chance with a bike pump . You need a much more stable source of ignition than you will get from clicking that grill sparker. I won't say it's impossible, but the better the ignition source the more wiggle room you have for stoichiometric variables. It's easier to start rich and lean it out with air, guaranteeing that at some in time you cross over the ideal stoic ratio and get some sort of start
Excellent info! This is exactly what I need. I watched other Pulse Jet UA-cam videos, but they don't explain their ignition source so I had to guess. I will also try a better CFM source like my leaf blower. I did see one video where he made a rubber bladder for the fuel source to make it more consistent. I will look into this further. I really appreciate your information you provided!!!
Not totally correct I have a pulse jet digger and it’s standard with what looks like a bike pump on top of it but it’s not only supplying air to the intake but to fuel tank as well
@@chadsmith9218 that makes sense, pressurize to feed the fuel .
@@chadsmith9218once it fires, doesthe engine draw the fuel on its own ?
@@iamnegan1515 yes it pressures both untill it fires then it does it all on its own.
Thats not even close to the smallest spark plug ! they go down to at least 1/4"
Now that's tiny!!!!!! Thanks for the comment!
I recently seen a video of a fully functioning pulse jet RC 1.15th scale plane and they used a leaf blower to get it to start up
I think the leaf blower is only needed if the pulse jet is of the open venturi valveless type. Reed valve pulse jets like this one don't seem to need loads of high speed air blown through to start them.
bring a constant airflow into the airintake. The fuel need to runbooble free.
Make sure after each atemp let run air with out fuel injection.
Bring airflow and start ignition then let run the fuel slow in.
Repeat. In case warmer air help or preheat the tube inlet before start.
Maybe instead of a spark plug, try a glow plug instead?
glow-plugs only work with methanol-based fuels. The platinum filaments help catalyze the high-temperature dissociation of the methanol.
Pulse jets are awesome, but kind of a mystery to me 😁
They are such simple engines though
Looks like you're sparking it as fast as your thumb can press the button. Gas stoves have repeating igniters. What if you rigged up something like that? Several sparks per second while freeing the other hand.
Great job, wonderfully done model. Even the full size pulse jets were tricky to fire and run, so I'd call this a real success. :)
I ran a bunch as a kid.... till the noise regs shut them down. You would be better served with a spark box that will give continuous spark. I started all of them with a big pump like you have. the will pop and fart until they build some heat.... but it will light off. I think that single spark ignitor isn't helping.
Great info! Thank you! I'm working on getting continuous spark now along with more volume of air. Stay turned!
I noticed that the valves where not seated. Take them off and gently take a little out of the bend. Just rub them with a socket 90 degrees to the bend to take a little out and remount so they seal tight.
You're correct,if the reed petals aren't sealing it won't fire up and keep running.
Warm it up before you try it heat gun blow it through it for a little then try them kind of engines don't like cold starts by Warming it up it helps make the gas in to Flammable vapors till it can get to.Self combustion temperatures Three aspects to fire heat ,fuel, oxygen. without one you can't have it
Amazing first built in 1937 similar to whittle Jet engine on his dads test bed in 1927 patent in 1929 while writing the book on the jet engine.
Nice work.
1946 !!! - impressive
Sounds like there is more metering valve tweeking needed. At least your close to the correct fuel air mixture.
Calibrate the read valve to seal perfect.
Congratulations from Brasil!
All heat engines needs air fuel and source of ignition. I think that you needs much more stable air and continual ignition at least until it stabilizes. You also need understanding neighbours and a good set of ear defenders because its basically continual detonation and unbelievably loud.
Also.
If the nose cone swings out try starting it with the nose out till its running.
I suspect the cone is to restrict air in during flight to meter air in.
Wow ❤❤❤
I have smaller spark plugs that go in Olson and Rice model airplane motors.
Years ago I had a Dyna Jet pulse jet, I have no idea what ever happened to it.
If you did not get the valve on the bottom to seat it's shown at the 2:01 point in the video you may never get it to run correctly.
I am 60 I have not run that Jet since I was like 12, I have one with a red cone close to yours, thanks for bringing me back down memory lane!
I feel like that rocket the day after eating a vindaloo.
When I was a kid I remember seeing those advertised in comic books and model airplane magazines. I always wanted one but never had any money (rubber band plane kits were $.29!)
Attempt#12...."Brrrrrrt" LOL
So cool!
You need to get the mixture correct by arriving at the correct amount of airflow with a starter blower. A leaf blower or a reversible vacuum cleaner may work better than the air gun . These jets need a low pressure high volume air supply.
Heating the tail pipe towards the front with a gas flame will stabilise ignition until it is providing it's own heat.
Heating the tail pipe so close to the fuel tank will be... fun!
Its not so much a matter of heat but getting it to create the standing wave. These engine literally ignite in one ignition cycle with the pressure wave propagating to the exhaust but then also reflecting back through the partial vacuum left by the expanding gasses cooling. This partial vacuum plus any forward air movement (ie: actually flying or a leaf blower) both contribute to opening the vanes for fresh air and the next combustion cycle while the reflected wave carries the still burning flame front back to the fresh fuel/air that were just taken in. Search youtube where you can find video of a pulsejet test where windows were cut into the motor that let you see the combustion wave moving back and forth inside. It's amazing to watch.
In the absence of forward momentum or continuous airflow through the inlet the motor will not product much power or run with much stability. This is why V1s did not take off under their own power but were instead launched to over 250 kmh to get the engine up to flight power. The launch process ignited the motor mere seconds before the launch because left on the stand the motor would commonly stall since it need only lose 1 combustion cycle to stop running.
might help to use the blow part of an old vacuumcleaner / hoover on the bigger pulsejets they often use a leafblower , it fired but i dont think it realy ran , the sound of a running pulsejet is way way louder , might try adding propane untill it heats up
I think you need a more constant flow of air. More about volume than pressure.
Keep going bud you are on the cusb
I'd suggest heating up the engine body with a torch. Pulse jets run very hot and they seem to run better after they get warmed up. Also, for the pressurized air you could use a battery powered air duster from Amazon for around 20 bucks or even a hose on the outlet of a vacuum, or an electric balloon inflator.
I read somewhere that extending the tailpipe with a well fitting tube can help with the back pressure to get it started.
maybe the thin sheet springsteel on the flatter valves got overheatet in the past time and not have the tension anymore to seal the combustion chamber in the proper way. It might be the case because it has the bluish tint. Probably it was used to power those Planemodels on a rope.
Yep they go bad quick
I was just about to mention that if this is a reed valve pulse jet then the reeds do get fatigued and distorted so don't seal properly against the seat face. The remedy is usually to make new reed valves from spring steel sheet. Photo etching is often used as a method of forming the new reed petals from sheet steel.
@@howardosborne8647 Spring steel dies really fast in the minijet, it's directly exposed to combustion (unlike, for example, the dynajet). I believe stainless is the recommended way to go for these. th eupside is these are really easy to make, none of that etching out petals stuff. The valves don't look too bad in this case, but they've definitely seen some action.
When kids had fun building and learning stuff i miss my meccano sets.😆
Roger that!
I know guys who played with these engins in the 1960s on u-controlled airplanes. When that engine starts you will need more than 1 c-clamp to hold it down. And using the bicycle pump is the right way to start it.
I will elaborate on this story. A friend of mine had a friend who had a u-controlled model airplane with a pulse get engine installed. We are going back to the 60s, no such thing as radio control, a u-controled airplane is basically an airplane on the end of 2 wires that you hold onto. The airplane flies in a circle with the pitch controlled by the handhold. He had never flown the airplane with the jet before. While the guys were trying to start the jet a crowd had gathered, to his amazemet the jet started and the airplane took off. The jet was so powerful he had to dig heel in the ground to keep it from getting out of control, you can imagine how fast the aircraft was spinning. Not to mention all of the people standing around in harms way.
Great video...👍
Would be a very good engine for a drone! It is cheap, powerful and light! I wonder why is not used in our days!
Yup! The Germans used it to power their V1 doodlebug bombs which were dropping on London during the Blitz.
‘Cause they’re not even vaguely efficient. Neat little toy, though. There were plans for a larger one a few years ago, ran on propane.
@@russbell6418 I don't refer at this very model, i refer to a engine which function on same way! In WW2 the German cruise missile V1 had a same kind of engine and it was faster and more powerful than a Shahed drone (for example) in our days!
@@klmn48a shaheed drone isnt exactly bleeding edge technology.
That’s so cool! I had no idea they made things like this that long ago.
Great noises - like an angry animal. Worth it for that!
Great video, been trying to get one of these for years with no luck.
Try a leaf blower or a compressed air tank. You are doing a great job sir and nice score on the old pulse jet!
Good idea Kris! Thanks! I'm on it!
Thats so cool, you could buy as kit
Great vid amazing to see a real working vintage one in miniature, and it runs but for a bit more tweeking and knowledge as another person has pointed out but fantastic hope to see more sir.
I like those things. Try warming the plug up a bit and the combustion chamber as well and maybe that will sort it out. Also make sure that the fuel tank has a breather to allow flow.
I'm not 100% sure but it looked like some of the airflow from the front valve goes to the tank to pressurise it, and the other pipe grabs the fuel from the bottom that's then pushed to the jets in the flame chamber.
an old "buzz box" from a mod.T...they were quite common back then...get it started, warmed and stabilized..good to go
Did anyone else laugh at attempt #12 @5:22?
@@meme-bj1pe I sure did!😁
I'd say a fail. Try more compressed air for a constant flow over a pump. Gotta keep those valves moving until start up and a few seconds later until the engine warms up some.