Scap Heap Challenge.

As per usual - no mention of the oil supply to the turbine bearings in the build etc, etc...

I do fancy the idea of a ram jet though.

Did anyone notice the JAP 4/3 which was lying abandoned at the edge of the 'scrapheap'?

Cheers

Dan

Hi Dan, Just towards the end of the build phase they did mention the oil tank but there was no reference to how the oil pump was driven. their reason for cancelling the last run was lack of oil pressure so they must have had something.

Cheers Paul

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Internal Fire, Museum of Power, Wales

(under construction)

I was fascinated by it all, but I notice the program was rather light on technical detail. Could it be that the idea of various enthusiasts armed with old turbochargers and propane gas cylinders, trying to build turbines in their sheds gave them the willies. The pulse jet looked like real fun though :-)) The V1 doodlebug engine had a set of reed valves on the inlet side, but last nights iteration seemed to manage very nicely without them. This is where a bit more technical detail would be nice. I'm not going to attempt to male one though, I have a shed full of dismembered stationary engines to work on. Anyone got a spare crank for a 1.5hp M type??

Regards

Philip T-E

Wrong newsgroup. Both experts are regulars in rec.crafts.metalworking and have large and informative websites.

New Zealand bloke's speciality - the Bassoon of Mass Destruction. Geometry is a bit awkward, if it's too work, but I assume he can do it from memory.

You can do a straight through pulsejet without a valve too, but it only works over a narrow range of airspeed, so you have to air-drop it.

If you're interested in pulsejets, look at '50s control-line model aircraft. They had some lovely ones with flower petal reed valves, petrol fuel and a sparkplug and trembler ignition.

-- Die Gotterspammerung - Junkmail of the Gods

"Andy Dingley" wrote

Hi, Built one in 1970 at school from plans in The Aeromodeller Yearbook. Still have it.

About 2 ft long with a 3" combustion chamber we had problems with the petal valve either melting or disintegrating. Ran on petrol and was started by putting a stirrup pump onto the tube at 45 deg from the main jet (see pics) and pumping hard whilst heating the rear of the tailpipe to cherry red. You had to get it off the ground fairly rapidly or the whole thing got a little hot.

Mounted in a control line aircraft it needed a pylon to take the weight otherwise the thing would rip your arms out. All up weight was about 8lbs.

You can just about see the valve at the back of the venturi.

School noisemeter registered 128db static on the floor - seriously loud :-)

Paul

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Internal Fire, Museum of Power, Wales

(under construction)

Use monel, inconel or titanium. Jet engine scrap is the usual source

You can tell I live in Bristol ! 8-)

-- Smert' spamionam

"Andy Dingley" wrote

The final/current valve was 30 thou titanium.

Paul

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Internal Fire, Museum of Power, Wales

(under construction)