Queen Bee on diesel

I adore diesel engines and that one is sounding on song. (Although difficult to be precise from a recording)

I have though had some difficulty with straight head conversions and found that the performance (and fuel consumption) improves if the venturi area is reduced.

Diesels don't normally respond as well as that to throttle - it makes me think that the Queen Bee and her setup was more suited to diesel fuel!

I wish You Tube did "smelly vision" - I could sniff diesel fuel for England!

It really liked the 7x4. I am impressed with your test setup.

Yes, timid and restricted glow engines seem to do very well when converted from glow to diesel. I guess the lower rpms used (in general) and the lower fuel consumption doesn't require the large holes in the carb and crank etc. that one sees in high performance gow engines. This makes the "timid" Queen Bee a very good subject for a conversion I think.

One trick that can help a little is to limit the throttle travel on the radio, the engine is often fully up to speed at around 75% throttle opening so the last bit is not need and can give a lower fuel draw.

I had some very strange behaviours though from the Queen Bee around full throttle until I realized that it will go well past full throttle, in stock form....

It is a simple machining error on the throttle barrel.

Looks like I have a good candidate for flight testing, a "TT Scooter".
I have run it on a PAW 09 RC in the last few years and it is almost too much power...

The queen bee should fit quite easily I think, the mounting beams are long so there is no problem with the rear carb other than making a cutout for the needle or raising the beams a little.

Hello Chris Ken, Ian & Cribbs.

I choose also Queen Bee    engine in the Scooter .07    airplane of Thunder Tiger.

There are two photos here that should be entered in the photo competition. Those engines sit well in both aeroplanes.

They look suited.

ian1954 wrote:I adore diesel engines.
I wish You Tube did "smelly vision" - I could sniff diesel fuel for England!

Spoken like a true English gent.  Most of us modellers from Down Under grew up on diesel fuel fumes as well.  Ah, my longsuffering mother never complained when I fired up the old Mills .75 in the spare bedroom.  Kind of like an industrial air freshener.

Rod.

Well, I have made some more of the precious scent today.
I have now flown the engine in the "Scooter" and it is plenty of power for it. In fact I will need to add some engine down thrust to reduce the climb at full throttle....

Here is a little movie of the engine on an APC 8x4 prop and inflight settings;

It is not just the smell but the sound. The low end bark that you hear - a little different to the glow whine.

Hi guys, these are my Scooter videos.

If you look the shape rudder is copied from Quaker airplane.

First Fly with original engine Thunder Tiger GP 7



After ... I mount very big foam balloon wheels of Fun Cub of Multiplex.



Here, me kid Paul learning to fly.



I promise make a video with Cox Queen Bee.

Nice videos - I like the training video - we all start somewhere and the younger the better.

One question friends, I need to choose a best easy trainer airplane 1/2 A to start to learn to fly control line.



Engine: Cox Babe bee  

lenght line: 8 or 9 meters?

Airplane:                ?

11 meters would be better on line length and if all you want to do is fly level laps then a Brodak trainer or a Goldberg Wizard would be my suggestion. A beginner Ringmaster is another good one. The Ringmaster flys better than the Wizard. If you cut the nose down a little then the Wizard flys well also.

The Brodak trainer is cheap and quick to build and repair. Once you master level flight and the odd loop then you can move on to something better.

Thank you, also is important easy to build, because it is for students school project.

I need also the plan.

I like Ringmaster, and I find plan in outerzone.

http://www.outerzone.co.uk/plan_files_05/5652/Baby_Ringmaster_22in.pdf

I think that big wing profile make slow flights and also more line lenght.

Hey Kris!
Have you run your QBee diesel a lot? How is it holding up? Looks like an interesting modification and sounds great on video.

A Queen Bee Diesel would make a nice engine for an RC Oldtimer type plane, as it is pretty heavy (helps with the short nose on many oldtimers), would turn a good size prop, and has the sound to match.

I have a well used QB laying around and an NIB one on the way (I know I shouldn't have, but it was one of those "spur of the moment" things again ).

I can't say that I have flown it a lot, but I have flown it a bit during calm summer evenings and the last time I flew it was monday evening this week. For me it is perfekt for the old-school type of planes for some relaxed flying. The larger props, compared to glow, works much better for slow flying planes with a large wingspan. In the TT Scooter I only need about half throttle for level flight and the sound is really soft and nice.

I haven't seen or felt any signs of un-normal wear but I haven't had it appart to check the reed or conrod slop etc. The key to low wear, in general, is to use good fuel and a large prop, this will keep the compression low and it feels only slightly higher than it would on a typical glow engine. For a successful conversion, I think the best is to start with a good cylinder/piston set, any leakage there and the starting can be difficult. My QB feels about average in terms of sealing, it will leak when turned slowly through TDC but seals fine when flipped over. For the first start of a day I usually increase the compression ratio a little (less than 1/4 of a turn) while hot starts, or starts between refuelling, can be done without changing the compression ratio at all or one can even lower it to get a better flywheel effect on the prop. It can help to flip the engine over while keeping the second hand on the compression lever for rapid adjustments.

After each outing I remove the two muffler screws and put some ARO on the piston and it turn over a few times. This is important in order to avoid corrosion from the exhaust residues. This happens more when an engine is run harder on small props, but it is a good habit to have I think. If not done, there can actually be substantial corrosion in less than 24h (that happened to me once on an MVVS engine).

The fuel I've used in the QB is a standard blend that I use for all my diesels;

Castor 25%
Ether 33%
DII 1.5%
Kerosene 40.5%

DII ? octyl nitrate this stuff why and where do you buy it? Eric

i love those RJL diesel heads
i dont have one
but the colour looks so cool

and for the cetaan booster
it is not needed
i never use it on my diesels

but i am thinking of getting some

The ignition improver helps to lower the compression ratio and I think that is very important for converted cox engines. I have run the same fuel in a PeeWee with its stock crank without any problems. I get the fuel from the only source I know of in sweden that will blend the fuel according to specification. I haven't played with the DII contents but in principle it the ideal value depends on oil level and ambient temperature etc. I have settled for 25% of castor as I have several plane bearing engines, and then 1.5% is a good enough average value I think. For sports use it certainly seems good enough, and I don't do any racing.

Another key thing is to have a good sealing head, the Teflon washer style ones are very dangerous as they will leak and trick you into increasing the compression ratio to get that first pop and once the engine fires the engine is well over compressed and something will give....

and that is why i replaced my teflon disks with aluminium

works great

Yes aluminium works but I have gotten better durability with brass (on the PeeWee engine).