Fox .09 Rocket Acquisition

706jim wrote:I remember getting one of these when I was just 11. It sure didn't look like the illustration in Model Airplane News. The main casting was incredibly rough.  It DID live up to its hype of easy starting plus the needle valve was safely away from the propeller.
I think its power output was about the same as a Golden bee.

It is good Jim, that you verified the observations of model magazine engine reviewers back in the day.

Looking at the articles in Spectre Flight, H.R. Warring got 0.11 BHP at 14,000 RPM on 20% nitro (Fox Missile Mist). H.R. Warring got 0.055 BHP at 13,000 RPM for the Babe Bee on 15% nitro.

Both him and Peter Chinn concluded a 7x3 was about the best prop for it once unloaded in the air. Not long ago, I put a 7x3 wood on my Enya .09-III TV, and it flew my 40" Cessna foamie like it had a .049. When I put a 7x6, it became a whole different animal, really moved out. (Enya HP peaks at around 12,500 RPM.)

I could see where the impression would be like a lower end .09 engine, especially if a lower nitro fuel is used.

They certainly are neat looking. It's good to see that no one butchered the case. Many cut the back off or lost the backplate.

Ken Cook wrote:          They certainly are neat looking. It's good to see that no one butchered the case. Many cut the back off or lost the backplate.

Yep, one of mine had a "hacksaw attack", with the rear of the case (fuel tank) being very roughly hacked off. It runs, but that's about as far as I'll go. My other example presents and runs way better. It's complete and runs ok but you need to be prepared to experiment with different props. Less is more. Over-prop it and and it will refuse to reach any sort of sweet spot. 7 X 3 sounds about right, but I don't remember what I ended up using. Some criticise the Gilberts for being low on power. In regards to performance I'd choose the Gilbert 11 over the Rocket any day. I know it's bigger, but being of similar design, I think the comparison is fair. The Rocket probably did the job ok as a free-flight engine.

Not a bad looking engine George , hopefully the glow head works . Are you going to clean it up and give it a spin ? I have a rocket .049 or .09 can't find it at the moment but did find an engine that took me on a adventure  Has no marking but can tell its a Fox from the glow head needs a needle and is a little gummed up but best i can figure its a Fox Comet .049 with the integrated tank . .  

That’s cool George…. Love those old historical engines….I’m sure you’ll shine it up and make a good runner!!! I think you can still get glow heads from MECOA if needed….. Looks like you have done your homework on prop selection and power output….. My CG Stuntman 23 lists this engine as an option on the assembly instructions…. Would be a neat combo…

Congratulations Jorge!!!
Here I show you my Fox Rocket.
I never installed it in any model aircraft, I always have many projects in mind, time has made me unable to do everything my head wants to do!!! ha ha ha

Oldenginerod wrote:

Ken Cook wrote:They certainly are neat looking. It's good to see that no one butchered the case. Many cut the back off or lost the backplate.

Yep, one of mine had a "hacksaw attack", with the rear of the case (fuel tank) being very roughly hacked off. It runs, but that's about as far as I'll go. My other example presents and runs way better. It's complete and runs ok but you need to be prepared to experiment with different props. Less is more. Over-prop it and and it will refuse to reach any sort of sweet spot. 7 X 3 sounds about right, but I don't remember what I ended up using. Some criticise the Gilberts for being low on power.  In regards to performance I'd choose the Gilbert 11 over the Rocket any day.  I know it's bigger, but being of similar design, I think the comparison is fair.  The Rocket probably did the job ok as a free-flight engine.

Good inputs, Rod and Ken. About those butchered cases, only thing I can think of that may sort of redeem them is to carefully file away and clean up the butch job. If someone has a milling machine, of course they can carefully mill away to that which cleans up the looks and makes sense.

Regarding overpropping, there are some other engines sensitive to that, whose torque curves require getting the engine to run at peak HP in the air for best performance. This is why I have enjoyed engines like the Enya cross scavenge, because they are less fussy. But it is good to know about this engine as the torque curve is not as tolerant.

I wanted to use the Gilbert .11 on my Berkeley Impulse kit build as it shows the Fox .09 on the plans. However, the cheek cowls are too narrow to handle the width of the mount flanges on the Gilbert. That narrowed it down to the Thunder Tiger .074 R/C, Cox .074 Queen Bee or Cox .09 Medallion .09 R/C.

getback wrote:Not a bad looking engine George , hopefully the glow head works . Are you going to clean it up and give it a spin ? I have a rocket .049 or .09 can't find it at the moment but did find an engine that took me on a adventure  Has no marking but can tell its a Fox from the glow head needs a needle and is a little gummed up but best i can figure its a Fox Comet .049 with the integrated tank . .
 

Eric, those half-A Foxes, from what I've read, are decent engines. I think Ex Model Engines still have a few they are marketing, along with some parts. Really don't know what I plan to do, but the engine caught my attention because it is the base engine used on the 1959 Berkeley 46-in. Impulse kit plans.

MauricioB wrote:Congratulations Jorge!!! Here I show you my Fox Rocket. I never installed it in any model aircraft, I always have many projects in mind, time has made me unable to do everything my head wants to do!!! ha ha ha

Gracias, Mauricio, tu motor es muy facil para reiniciar. Your engine is very easy to restart.

706jim wrote:

rdw777 wrote: My CG Stuntman 23 lists this engine as an option on the assembly instructions…. Would be a neat combo…

The plans show the Fox 0.099 radial mounted with the 3-48 nuts glued behind the firewall, most likely with Ambroid as epoxy and CA had not yet been invented. Imagine the frustration (mine!) of trying to get those tiny fiddly nuts in the right position behind the firewall keeping in mind that they had the dual duty of holding the engine in place AND sealing the integral tank in the crankcase casting.

In my case my father came to the rescue by fabricating a sheet metal mount that screwed into the cowl cheeks.

My new (and generously donated Stuntman) will probably be powered with a Babe Bee. Why this particular choice? My Black Widow is fatally rusted and the Babe Bee will be both less powerful and will run for a shorter time. As all of us U/C pilots know, once you're airborne you are committed to many dizzy rotations until the tank runs dry. And they will be slightly slower with the Babe Bee.

I think the Babe Bee is a good choice. Yes, I know how those dizzying flights are. An 8cc tank would add another minute of dizzying flights.



Here, Walt Musciano in his early 1950's Fokker Dr1 Triplane with 24 inch wingspan considered the Fox .09 as minimum power for it, with the K&B .23 Torpedo being maximum. Probably a Testor McCoy .19 Red Head would be about right, a modern sport Schneurle .10 plain bearing engine, too.

706jim wrote:Should you own one of these that has been subjected to a hacksaw attack, I have access to a machining center and can clean up the end of the crankcase casting if there is enough remaining metal to do so. Your only cost would be the shipping to and from my home In Thunder Bay.

Sounds like a good plan, Jim. With a cleaned up "custom engine", could be a show piece on an aircraft than a basket case.

706jim wrote:My Fox is long gone but it would be neat just to see one of these again after all these years.

I picked up mine for a song, person discounted the price a touch with only a few hours left to buy now. That's when I clicked "add to cart". Perhaps one will come along for you to buy, or someone donate to you their bastard case for you to clean up and enjoy.

That seems like a good deal for the engine George….. Tempts me to watch for one…. Between your purchase and Jim’s offer to repair sawn off backs, You guys may have driven the market up on Fox Rockets!!! ….Share some photos and assessments when you get it George

Robert, I serious doubt we drove up the Fox .09 engine real estate costs by our actions.

It arrived today, was a little stiff turning because of the congealed Castor, but a couple shots of Gunk Super Oil in the venturi opening, engine nose area by the prop thrust drive plate and in the exhaust port to piston top freed it up after a couple flips. A 2-56 screw and nut were used to hold tank back with it. It was slightly sprung, so careful tweaking with needle nose pliers restored the bent mount corner to original flatness. I can easily make a paper fuel tank back gasket if I ever were to use the tank.

Because of the tank's lightness, there really is not much to be gained by hacking it off. The ability to bulkhead mount the engine I feel is worth it. Regarding concerns over mount screws holding the back in place, the Cox .049 Ranger, R/C Bee and Dragonfly all use the rear mount screws to hold the plastic tank back in place. I never had any problems with fuel tank leakage on my R/C Bee through its many flights on my Minnie Mambo.



I was surprised to see that one can still buy Gunk Super Oil, now in a plastic squeeze bottle. My can now looks like a historic relic.  

Think I will do Bob @rsv1cox's cleaning method, use an old toothbrush with MEK solvent to clean the outside, no reason to disassemble.

Holding this engine in my hands is a sight to behold. Compared with my Fox .25, this little jewel has a very clean, immaculate block casting, something truly marvelous, a truly quality 1950's work of art with the casting technology of the day. The engine for its size is very light, Peter Chinn measured it at 3.1 oz. tank back included.

IMO, it would be a good upgrade to add a touch more power to an anemic .049 airplane. 0.111 BHP at 14,000 RPM on say a 7x3 prop will have more thrust than a baseline Sure Start or Babe Bee with 5x3 or 6x3 prop.

I tried to find information on its tank capacity but had no luck. My guess is may be 7 cc, enough for 1.5 to 2 minutes of flight.

A few more photos, showing the tank arrangement. Again, the casting is thin but strong and very light.

Tonight, I did a little "field" cleaning versus "shop" cleaning. Using an old toothbrush and acetone, I scrubbed away the Castor stains mixed with dust. Crankshaft prop threads and nut were filled with hardened Castor, now clean.



I notice that when flipping the newly mounted APC 7x3 prop, there is a slight bubbling at the glow head. There is a possibility that it lacks a glow head gasket, as this should seal perfectly.

Later when I get a chance, I might have a sheet metal wrench that fits the head. In my flight box, none of the Cox or Gilbert wrenches fit. Worst case is a section of leather wrapped around and vice grips or pipe pliers to remove.

All considering, it cleaned up quite nicely. Don't know if this is a rumor, but heard that the Gilbert .11 Thunderhead heads should fit it. When I get it off, will know more.

Bob @rsv1cox's cleaning method of using carburetor cleaner definitely has merit on engines that don't require a complete disassembly. Acetone cleaned it up, but not as thoroughly as Bob's methodology and required a little more elbow grease. I'll need to buy some and try it out. I also got an almost full gallon of MEK, but didn't have my pliers handy to open the can. However, that definitely requires gloves, not good for bare skin to handle.

GallopingGhostler wrote:

I notice that when flipping the newly mounted APC 7x3 prop, there is a slight bubbling at the glow head. There is a possibility that it lacks a glow head gasket, as this should seal perfe

George-it SHOULD have an aluminium head gasket fitted-but many don't seem to (at last the ones that have passed thru my hands over the years....) I don't know if replacement glowheads (available from Mecoa) come with a gasket like OEM Cox ones used to..... I do know that OEM Fox 09 gasket sets included a head gasket.....

ChrisM

George, send me your address in a PM and I can provide you a complete gasket set. There could be a chance that I'm one of the very few that has many parts for this engine. I have all but cases, however, I'm not providing parts at least at this particular time. I have categorized most of my Fox parts in a card catalog style which makes it easy for me to locate the small stuff such as what your seeking. This is free of charge as I don't want any money for the items just the satisfaction knowing that one, your interest in this engine, and the other that I know you will get around to using it someday. I just went down and pulled out a gasket set . The gasket set includes the cork backplate gasket, the small gasket for the backplate (thin and fragile) and the head gasket. The envelope is marked 25 cents. NOOS one would say, new original old stock.

I would also like to comment on your prop. The APC is heavy and it could run risk of breaking the crank. If it's all you have, I would lean on the light side with nitro like 10%. If you have woodie props, I would certainly use them on this engine, I've had this engine do funny things at times when it was loaded such as run forward and then backfire only to run backwards. This is where the APC could cause problems. I prefer the Cox grey 6x4's on this engine, it does sound a bit on the light side but the engine is certainly no firebreather.

As far as plugs, I do have them but I'm uncertain of the number. Duke was associated with the Gilbert engine lines and your correct in terms of the plug being able to be interchanged. I don't recall if it's the .07 or the .11. The one thing with the Gilbert plugs is that they're frail and they certainly can burnout or stop working in short order. In my experience the .07 is certainly more susceptible to plug problems vs the .11. I forget if this plug interchanges with the TD .09 I could certainly try and if so, we always have Kamtechnik as a solution with turbo plugs.

Thanks, Ken! (sent you a PM)    

Also, thanks for the advice on fragility. I didn't realize the Fox was somewhat delicate and to use wood props if possible. I do have a Masters 7x3 plastic prop that is a little lighter. Would it be a better choice? I don't have a 6x4 or 7x3 wood prop, only 6x5, 7x5 and 7x6 wood props.

Oddly enough, I found that my 1965 Enya .09-III TV actually needled and throttled better on wood props. On the heavier APC, it didn't like it, was harder to needle and inconsistent. Its bigger brother, .15-III TV had no problem with plastic props.

Thanks for the advice on the Gilbert heads. When I remove the Fox head, then can check whether my .074 or .11 Gilbert head fits.

I purchased extras when forget his name now, who cleaned and sold Gilberts for a long time on E-Bay, offered heads as well (until his well ran dry). If push comes to shove, I have a 1/4x32 tap. I can tap a bad Gilbert head and install a plug.

You got the engine cleaned up nicely George… Certainly a unique look with the smoothed off head and rear facing venturi….Kudos to Ken on the parts offer…. Hopefully you can come up with a wrench to work the head…. Good luck with rehab

Thanks, Robert. I just found an example of what @Ken Cook was referring to, a hacked off back. This one curiously has an A.C. Gilbert Thunderhead head on it, may be the .11 one:



(Those interested in purchasing, see: https://www.ebay.com/itm/334815607282

If I had it, I would carefully file the back saw cut flat and even with a file, then lightly chamfer the edges to break the sharpness.)

I don't like seeing that. Unfortunately, almost everyone I see is like that.

GallopingGhostler wrote:Thanks, Robert. I just found an example of what @Ken Cook was referring to, a hacked off back. This one curiously has an A.C. Gilbert Thunderhead head on it, may be the .11 one:



(Those interested in purchasing, see: https://www.ebay.com/itm/334815607282

If I had it, I would carefully file the back saw cut flat and even with a file, then lightly chamfer the edges to break the sharpness.)

George-that's actually a Fox .10 head not a Gilbert....the spanner flats are a dead giveaway...all the gilbert heads had two small slots for tightening..[the Gilbert 11 head will fit though....and vice versa]

ChrisM
'ffkiwi'

ffkiwi wrote:George-that's actually a Fox .10 head not a Gilbert....the spanner flats are a dead giveaway...all the gilbert heads had two small slots for tightening..[the Gilbert 11 head will fit though....and vice versa]

Yes, you are correct, Chris, thanks for clarifying. The Fox .10 head does have a resemblance to the Gilbert. Not have one of my Gilberts in front of me, forgot how they are wrenched. Also thanks for verifying that the Gilbert head will fit, too.

GallopingGhostler wrote:

ffkiwi wrote:George-that's actually a Fox .10 head not a Gilbert....the spanner flats are a dead giveaway...all the gilbert heads had two small slots for tightening..[the Gilbert 11 head will fit though....and vice versa]

Yes, you are correct, Chris, thanks for clarifying. The Fox .10 head does have a resemblance to the Gilbert. Not have one of my Gilberts in front of me, forgot how they are wrenched. Also thanks for verifying that the Gilbert head will fit, too.

George-it will FIT....how it will run is another matter, given the generally held view of Gilbert heads.... As I've noted here before the Rocket 09 and the Hustler .10 share several parts in common-the piston/cylinder/rod -the crankshaft-and the prop drive components....so obviously the 09 glowhead and .10 glowhead are interchangeable.....what I don't know for certain is whether the two heads have the same internal shape and combustion chamber profile....I'd hazard a guess that they do, knowing Duke Fox's propensity for using components over several engines! When my Hustler arrives-hopefully in the next few days-I'll be able to check against both the 09 head and the Gilbert 11 head.

By all accounts the Hustler .10 was quite good..a lot better than the 09-its a surprise it came and went almost un-noticed in the market -I guess Cox had the 09 side of things sewn up....at least in the USA. FWIW the Hustler was sold in the UK under the name 'Gremlin'...by a firm 'Bradshaw Model Products'-with no indication that it was a Fox product. Thereby hangs a tale....which I suspect we'll never find the truth behind....

ChrisM