Cox .074 Queen Bee nelson plug

Here is some data I have on hand.

Queen Bee .074 with a HQ Prop 5x4.5
New engine broken in with 2oz of fuel thus far here are the results
with the stock cox supplied glow plug and adapter. I do have a Merlin
flat coil plug I want to try as it will increase compression.

Static: 18,195 rpm / 9.5oz / .122hp / 91w / 78 mph
I think there is another 1k rpm after some more tweaking
Throttles well and should unload to 22.2k / 95 mph


Couldn't help myself slapped a Profi pipe on to test a cut down MA 6x4 to 5x4
Static 19,379 rpm / .133hp / 99.22w / 10.7oz thrust / 74 mph
Not bad for a Queen Bee 1.2cc / .074 cu. in. Have not checked the timing
I imagine it is typical around 140 deg exhaust timing could do with a bump
to 160. I did not install this pressure tap the previous owner did it but never
ran the engine.

I see that you guys are getting real good performance out of the Queen Bee.I ran mine again today but went up in nitro to 25% With 20% all castor and 55%methanol. Running the 6 x 3 cox grey prop I was able to get over 18,400 rpm no muffler with the muffler I got 17,900 rpm . I tried to take a pic with the engine running and holding the tach and camera I went to adjust the needle and my hand brushed the prop so no action shots from me. I washed my hand and used some medium CA to cover the cuts and continued doing engine runs. I will be careful and continue to take my pics of the tach when the engine is off.
                                                                                                                          Juan

Much better
A bit of nitro helps to cool the engine too.
I like using a phone app called "RPM Gauge" to keep my
hands free. Some folks use a stand to hold the tach another
good option.

Ouch! Lucky the injury doesn't look too bad, and we have all been there...
It is good to have a certain routine around a running engine, like always standing behind the engine etc. That way there is less risk of trying to reach through the prop arc and other bad things.

Those are good numbers, I would still recommend to try a few different head shims in order to see what happens to the needle position and max rpm. Once you find were it peaks (for a specific fuel) then add one more head shim to stay on the safe side. Squeezing every last of bit rpm out on the bench doesn't always work the best in practice, you want to have a well behaving engine that is easy to start and insensitive to the precise needle setting etc.

I converted a Queen Bee .074 to a Queen Bee .09 by swapping cylinders and pistons and learned something in the process.  First I learned that threading is the same for both engines.  Next I learned that the crankpin on the .074 is smaller than the Tee Dee .09's so I made a bushing for the connecting rod.  Then I learned that the combustion chamber in the head of the .074 is much smaller than the one in the .09 head.  My new Queen Bee .09 ran only on the larger chamber.  .09 heads can be used to experiment with Nelson plugs or with Turbo plugs including making buttons of various chamber shapes.  The newly created Queen Bee .09 ran almost identically to the .074 but with the larger props (7x3) it moved much more air

gee guys i wished i had half your knowlage an tooling...i have two queen bee's one is with out a head because its build from spare sparts...i would love a moderfyed version

I'll tell ya the biggest problem I see with most factory "mufflers" is that 90 degree turn exiting the cylinder.
If you look at most tuned exhaust systems it exits straight out with very little resistance. I think the resistance may be contributing to the over heating.
this why I tried to keep the flow as smooth as possible in my custom pipe. but until I get a chance to test it, its hard to say.





Basswood

Update on the Queen Buzzer...



Cox Queen Beast .074 / Kamtechnik Turbo Plug Adapter Test
Works with the .074  and Tee Dee .09 / Tested with a APC 6x3
Static Peak 19,783 rpm  / .214 hp - 158w / 56.2 mph pitch speed
Impressive 23.3 oz thrust!
OS P4 turbo plug / 25% nitro / 20% oil

In making adapters for the Nelson - or other - plug folks aren't generally aware that the cylinder fit is the same as the Cox .09.  The 09  has a bigger dome but it works on the Queen Bee.  The standard Queen Bee plug is too high compression for the TD .09.  I would like to see someone make an adapter from the TD plug to fit the Queen.  I made a crank bushing that allowed my Queen Bee to accept a TD .09 piston and cylinder to convert it to an .09 Queen Bee.  It ran much better than the .074 version but not quite as good as the TD .09.

I used the same turbo plug and adapter shown with the .074 vid to test the TD .09 / I don't recall how many shims used.
The RC conversion engine created 2 lbs. of thrust and .331 hp - 247w of power with a 6.25 x 3.25 glass combat prop.

Update was 2 head shims.

That is one sweet looking engine ya got there 1/2 A.
Basswood

But I have to say I just ordered one of those radial screw in rear T.D .051 mounting plates on ebay the other day for an engine I'm working on. I just liked them as soon as I saw them.
as far as stock Tarno carb I'm still up in the air on that. even on a 074

Basswood

Took 2 head shims I found the post.

The radial mounts save the weight of a nylon engine mount and 4 additional screws required.
With the engine beams removed the firewall gets 4 screws and your done. The area helps to
wick away heat from the crankcase. No reason to use a Tarno carb with a QB .074.

 

May be No reason to put a .074 QB carb on a .049 reedie either but here ya go. I know its a bit of a Frankenstein engine, but ya never know! I suspect the air mixture in going to be too lean.but it may run with the screen.
just have to wait for bench testing.








Basswood

Nice!  

It should work as long as you have a good seal going.
Can you post a close up pic of the interface.

Witness the King Bee .049



92 mph pitch speed with a APC 4.44 x 5

1/2A
That's Nice. I didn't know anyone else had tried something similar. mine does seal with a standard .049 gasket. But one of the differences with mine is I also have a much cleaner version of this carb conversion planned.
I'm going to use a cut down .049 reed assembly on it made from a Avion .049 reed assembly as used on some of my other .049 Tarno style mount rear induction mods.
I'm going to use a Q.B carb and .049 reed assembly. Take a look at the photo and you can get an Idea how I'm going to do it.
Also a custom made (shape)reed.I have my reasons and will explain more later.
I'm still waiting on some equipment to arrive in the mail, digital RPM meter,new digital camera for video's etc. so I can at least throw some numbers back on the bench test results.
even though I'm using a Cox .049 for the test.I also think I can answer some of the questions about intake and exhaust on the Q.B. engine with this test.




Basswood

Nice engine, with some neat mods!

Throw one of Bernies Sure Start high performance cylinder/pistons on that golden bee and it will be a real hot setup! Add a Tee Dee head, Nelson or Turbo plug conversion and you will have maximized it's power potential. Took Cox many years to achieve that with their Venom and Killer Bee reed engines, but your Golden Bee should be more reliable, with it's standard weight Sure Start piston.

Bill

Hi Bill if you look close, it is one of Bernie's or Matt's modded sure start cylinders on my engine. ( Thanks Bernie and Matt for some of the parts) and I have a multitude of different heads and glow plugs to try on it.  I'm also going to use one of my custom made tuned pipe/mufflers on it too.
Its going to be fun to see what numbers come out of this in bench testing.
Basswood

Yes, I missed those non-anodized exhaust ports, sorry!

I love the Sure Start top ends, but Estes must have missed the final ball joint re-seating step, as all of mine seem to need re-seating right out of the package.

All my new Cox engines on the other hand have been fine right out of the box. Did Bernie or Matt fix that on yours? I've yet to use mine, but will check them when I do.

Have a Kamtechnik Turbo head for my Cox .049, but still waiting for the Cox .09 turbo heads.

Looking forward to the report of final testing on your engine.

Bill

Bill I have not had a chance to test these new (Black) rods and pistons and re-cut cylinders but from what I've been hearing they are the way to go. and of course the new brown (oil) hardened and tempered killer Bee crank shafts too. We will see. Because I'm going to push the RPM limits on these and we will see how well they can stand up to it.


On another note.
Here is a part I just got today and I like It.It has an extra wide manifold around the cylinder.
It is a Enya M492 muffler. It will not fit a cox .049 out of the bag but I think with some tweeking it could be a great muffler/pipe for the Q.B. and cox .049's
It is still currently available at a very reasonable price of $11.00 PSH on ebay (last time I checked)so that's not an issue either.
More later on it. More testing, I better get more fuel. The NEIGHBORS are going to love me. I'll just tell them Its a high performance micro weed eater engine I'm working on.  





Basswood

Basswood,

Is that really your name?

I've never seen one of those mufflers, but it sure looks like it would be easy to adapt.

I have and still own a few Enya engines, but can't imagine that 492 muffler suiting any of them? What the heck was it made for?

One of my best friends moved to Phoenix over a year ago. I was planning to visit them last year, but he suddenly passed away. I've always wanted to visit the VSC stunt event held in Tuscon now and that would have been a great trip.

Keep me posted on your engine testing please.

I'm hoping to test the new Bernie back plate mount on one of my Pee Wee engines. The only time I've flown a Pee Wee powered c/l airplane (Scarinzi Queen Bee), I was always wishing for a longer engine run. Now I don't fly anymore, but can at least test the back plate mount with a larger tank.

Bill

Those muffler were made for the .049 and .061 engines by Enya: