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Newbie's Golden Bee Hop-up

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Happy Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Tue Oct 11, 2016 9:31 pm

I know many of you have "been there, done that" so, before I do something I'd regret, I have some questions about my stock, single bypass GB:
More fuel burned of course, but what rpm increase might I expect from:
1) Intake opened to .082
2) Black Widow cylinder
3) Both of the above

One other multi-part question - is the inlet screen removable/replaceable or does it get destroyed?
If destroyed, what's the common fix?

Thanks.
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Happy Re: Newbie's Golden Bee Hop-up

Post  RknRusty on Tue Oct 11, 2016 10:45 pm

You might have a golden colored Black Widow. Did you  open both the inlet hole in the backplate and the rear opening of the venturi tube to .082? If so, and if the front hole of the venturi opening behind the reed is as wide as the one in a BW tank, and you have a pre-'96 cylinder with a #1 stamp then you have the equivalent of an original BW.
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Happy Re: Newbie's Golden Bee Hop-up

Post  Cribbs74 on Tue Oct 11, 2016 10:48 pm

You will get as much power as a black widow.

Throw a TD head with the correct shims in that mix and 18K+ would be possible. As far as the screen goes, you can pop it out from from the tank side, it will probably get destroyed, it is possible to put it back in although, it will not look as it did from the factory. Personally I would leave off.
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Happy Re: Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Tue Oct 11, 2016 10:57 pm

I haven't done anything yet - waiting on the claimed-to-be BW cylinder assembly to arrive.
I just want to be sure it's as simple as I understood it to be.
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Happy Re: Newbie's Golden Bee Hop-up

Post  pkrankow on Wed Oct 12, 2016 7:32 am

Go here
http://coxengines.ca/engine-and-fuel-guides.html

Find this document
Gibeault Mouse Race Program

Read it carefully. Not every part of it is critical for sport flying, but the tips are very helpful. Using smaller air passages is going to make a milder engine, but it will start easier. The recommended sizes are an excellent compromise on performance and ease of operation. I use a more convenient compromise of 5/64 inch, and accept that there is room for more performance (5/64 is a standard drill size that might already be in your drill index, as opposed to a letter size that you might have to go purchase).

Next go to the local auto parts store and get some anaerobic or aluminum safe sealant to use for assembly.

Build your engine. Run your engine. Enjoy your engine.

Phil
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Happy Re: Newbie's Golden Bee Hop-up

Post  fredvon4 on Wed Oct 12, 2016 7:52 am

What Phil said...especially reading Paul Gibeault's tips
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Happy Re: Newbie's Golden Bee Hop-up

Post  crankbndr on Wed Oct 12, 2016 9:28 am

My Golden Bee ran for about three min. at 14K+

https://www.youtube.com/watch?v=sIEo6xxIVn4


The Black Widow I made for the Tach Race ran about 40 sec., 20K+ on the same size tank
They really suck down the fuel, both with same fuel and prop

https://www.youtube.com/watch?v=eU6xQEkngkI
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Happy Re: Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Wed Oct 12, 2016 10:14 am

Thanks for the link, Phil - Paul's treatise is easily understood and covers everything I had in mind and more. This Site Rocks!

Crank, your videos give me pause - 40 secs isn't much flight time! Huh...
It's been well over a year since I ran this engine and IIRC it turned ~14K.
I think the smart thing to do is to first check the engine for leaks, etc., make sure all's good, run it as-is then consider how much I want to mod it.

Thanks for all your input, guys!
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Happy Re: Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Wed Oct 12, 2016 11:01 am

OK. For starters, I ran it as-is, 5.5x4 MA and 15% Super Power (smallest prop, only fuel I have on hand) and it's turning 14K.
Whadaya think guys -good Bee? OK Bee?
I haven't run 1/2As since the '50s and only Cubs & Wen-Macs then.
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Happy Re: Newbie's Golden Bee Hop-up

Post  pkrankow on Wed Oct 12, 2016 2:16 pm

It is a good bee. You might want to keep that one whole and build a hopped up parts engine.

Phil
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Happy Re: Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Wed Oct 12, 2016 2:37 pm

Well, alrighty then - I'll try it on my 20-year old Built-In-The-Motel-Over-The-Weekend-During-The-Only-Nats-I've-Ever-Attended-And-I-Wasn't-A-Member-Then-But-Volunteered-And-Have-The-AMA-Staff-Hat-Nametag-And-Pin-To-Prove-It-With-Stickers-On-The-Wing-But-Never-Been-Flown Commemorative Skyray.
If I need more power I can always mod it later.

Thanks to everyone. Beer Cheers
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Happy Re: Newbie's Golden Bee Hop-up

Post  pkrankow on Wed Oct 12, 2016 6:07 pm

That's a mouthful. We need pictures.

Try 25% nitro, you will like it, but it will require more head gasket shims. (probably 1 more over the count in there for 15%, but maybe the same. Gotta tach it with different counts to find out.)

Phil
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Happy Re: Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Wed Oct 12, 2016 6:40 pm

It has a standard head, 1 gasket.
I have parts, props on order; need to see if Hobbico Cox or Sig is available in my area.
Here's a pic - nuttin' special, except to me.


Hard to do a 20 point finish in a motel room. lol!
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Happy Re: Newbie's Golden Bee Hop-up

Post  Marleysky on Wed Oct 12, 2016 8:10 pm

Hey! I'll grant you 15 points just for building and finishing it in a motel room!! Seem's to me we have another member who builds piles of balsa dust in hotel rooms! I'll bet the fragrance of clear dope is much better than the air freshener the motel uses to cover up that moldy smell! RC Plane
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Happy Re: Newbie's Golden Bee Hop-up

Post  roddie on Thu Oct 13, 2016 9:19 am

wha-tah-hey wrote:Well, alrighty then - I'll try it on my 20-year old Built-In-The-Motel-Over-The-Weekend-During-The-Only-Nats-I've-Ever-Attended-And-I-Wasn't-A-Member-Then-But-Volunteered-And-Have-The-AMA-Staff-Hat-Nametag-And-Pin-To-Prove-It-With-Stickers-On-The-Wing-But-Never-Been-Flown Commemorative Skyray.
If I need more power I can always mod it later.

Thanks to everyone. Beer Cheers

Hi Terry! Now that's got character!



Muncie must have been an awesome NATS to take in back in 1996! I went with my dad in 1992(2) when they were in MA. We were just spectators..

Why not order another Skyray through Sig Manufacturing.. along with a pint of each; Champion 25/35. It would probably cost around $50 with shipping to AL.  Or throw-in a 1/2A "flight-pack (includes a pint of Sig Champion 25, a decent Sig handle, glow-clip. Dacron lines and a fuel syringe.. for probably less than that! Save that vintage keepsake for memories!
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Happy Re: Newbie's Golden Bee Hop-up

Post  getback on Thu Oct 13, 2016 10:07 am

That looks Great man , greenie for U ,Good Luck and Happy Landing Sir ! we Love videos also if you can I Love This Forum!
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Happy Re: Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Thu Oct 13, 2016 10:34 am

I appreciate the kind words, fellers.
I have flight accessories, prob is I'm an hour away from the club flying site.
Sad thing - I have plenty of room in the backyard to fly 1/2A.......if it weren't for the DAMMIT! verdammt TVA transmission lines overhead!!! DAMMIT!
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Happy Re: Newbie's Golden Bee Hop-up

Post  pkrankow on Thu Oct 13, 2016 12:43 pm

Don't play with wires. Sorry that is your back yard.

That is cool. I like the simple finish.

Phil
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Happy Re: Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Thu Oct 13, 2016 1:21 pm

Thanks, Phil.
I know these rich young fellers can afford colored paint, store-bought props an' such geegaws.
Wye, when I was kid if I wanted a prop I hadda chop down a tree first..... converted my GHQ to a woodburner 'cause it wouldn't run on coal oil...built my models outta whatever I didn't hafta eat first...  walked 3 miles to school everday - uphill both ways - an' I.......... uh..........

What was the question?




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Happy Re: Newbie's Golden Bee Hop-up

Post  roddie on Fri Oct 14, 2016 11:46 am

wha-tah-hey wrote:OK. For starters, I ran it as-is, 5.5x4 MA and 15% Super Power (smallest prop, only fuel I have on hand) and it's turning 14K.
Whadaya think guys -good Bee? OK Bee?
I haven't run 1/2As since the '50s and only Cubs & Wen-Macs then.

Terry, The 5.5 x 4 MA.. is a prop that I think you'll want to keep handy. I think that prop would run well on a Black Widow configured engine running at last 25% nitro fuel. On a stock Bee engine having a venturi-size of .062".. you might want to obtain some props in the 5" x 3" range.. of varying manufacturers and varying materials. I had been in the practice of over-propping my Bee engines, before becoming a member here, and learning about the effects that it poses.

A 5.0" inch diameter prop with 4.0" of pitch, is pretty much the maximum you'd want to run on a stock Cox .049 reed-valve engine for general sport/stunt flying. I'd personally obtain at least one of that size.. and a few 5 x 3's. I've run the gamut with prop-sizes and differing material-compositions on my flying-models. I find it to be fun as well as educational to try running different props. The Cox "black" props are made of a "flexible" plastic that can actually "diminish" in pitch when running.. whereas the Cox "grey" (competition) props tend stay "true to their pitch".. because they are more stiff/brittle.. and as a result; the grey props will break much easier when subjected to shock.. where the black props will flex to avoid breaking. The Cox PT19 Flight Trainers were designed to use 6 x 2 L/H props.. and their .049 engines were fitted with L/H spring-starters.  

Years ago (at least 25..) I bought-up several "J-Zinger" R/H  woodies in 6" x 3", 6" x 4", 7" x 3"  and 8"x 3" sizes. I had non-Cox .09/.15 engines that I could use the 7"/8"diameter  props with.. but I did try running them with the hub-holes "bushed" to fit the Cox .049 reed-engine's 5-40 threaded (1/8" OD) prop-screw, to see if the engines would sustain a low-rpm 2-cycle run. Mine did. The 8" X 3" Zinger woody flew a custom/profile sheet-wing 23.5" w/s biplane that I built.. which was just a "roundy-round" model. It ran a stock Cox .049 reed-valve crankcase.. with a product-engine equipped horseshoe backplate and an external 8-10cc wedge-tank. It was a stock engine; stock/Cox glowhead with one copper head-gasket, running Sig Champion 25% nitro. The NVA was stock too, and could be set barely to achieve a 2-cycle run.. albeit a low-rpm one.. but still in a 2-stroke power-band which was powerful enough to achieve a R.O.G. take-off from grass.. before the engine peaked-out in the air. Again, I was running a very lightweight prop. A heavier plastic/composite prop would likely not permit the engine to break-into a 2-cycle run, but I haven't ever tried one.

The Cox engines will run over-propped.. but depending on "how-much"; will cause the engine to "lug".. which stresses the fit of the ball-socket end of the rod-joint over time. This ball-socket joint however, can be checked for fit, and reset with a special tool. It's a good tool to have. It's just one part of the engine that needs periodic monitoring.

The below photo(s) show the tool.



Note that the instruction-sheet states; For use on Cox .020, .049/.051 and .09 engines but the tools themselves are naturally different for each engine's piston size. The tool shown is for .049/.051 engines only.





If/when you find the need to reset the piston/rod's ball-socket joint.. set the fixture that holds the inverted-piston on a hard-surface.. insert the inverted-piston in the holder, slip the connecting-rod into the groove in the punch.. and align it on-center into the fixture. Tap lightly with a small hammer.. while rotating the connecting-rod.. until the "play" is taken-up. You should be able to "spin/twist" the rod whist in the socket. If the fit is a "little" tight.. no worries. The castor-oil in the fuel's lube-package will take care of that.. and penetrate the joint. Too much play in this joint can cause the rod to wear-through the top of the piston.. or even separate from the socket.

You can elect to run "hot-rod" engines later on... once you get the "feel" of the stock-Cox engines. I'm still learning about tuning. Regarding tanked "Bee" engines; air-tight sealing is of the utmost importance. Your Golden Bee/Silver Bee (8cc tank's) four 2-56 threaded screws, should be checked to be sure that they thread into the crankcase so as to tighten the tank-assembly before the screws bottom-out in the crank-case. The screws are usually long enough but occasionally, one or more of the four holes aren't threaded deep enough into the crankcase. That condition can cause air-leaks within the tank.. because the screw(s) tighten before the tank/gasket/back-plate are drawn-together to form an air-tight seal. This can be corrected by either slightly shortening the screws.. or re-tapping the 2-56 threads in the crankcase with a tap of that size. The crankcase screw-holes are usually drilled deep enough to cut an extra few threads. If you have this condition.. it can cause trouble. The engine may run erratically.. and you'll lose raw-fuel due to leaking. It's also entirely possible to receive slightly longer case-screws in a rebuild-kit, which could cause this condition when you reassemble an engine.

Some of what I wrote here is mentioned in Paul G's Mouse Racing article.. but it doesn't hurt to reiterate some points that can be applied to general sport-running of your engine.
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Happy Re: Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Fri Oct 14, 2016 12:05 pm

Great info, Roddie, thanks!
MOF, I have a reset tool on the way.
Others have also recommended 5x3 as a good "baseline" prop, so they're on my list.
I don't seem to have any leak problems, but I'll get extra gasket sets and follow Paul's sealing procedure.
I'm fully content to run stock for a while, previously thinking stock might not really fly well and just got carried away with the notion of a hot rod. Very Happy
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Happy Re: Newbie's Golden Bee Hop-up

Post  pkrankow on Fri Oct 14, 2016 7:11 pm

Unless a rubber duckie prop, then a 6x3 or 6x4. The props flex and de-power so the extra area is needed for adequate performance.

Phil
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Happy Re: Newbie's Golden Bee Hop-up

Post  wha-tah-hey on Fri Oct 14, 2016 7:40 pm

Cox gray 5x3 is what I was thinking.
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