bsindel

Hi Gang,

I got this little 049 in with a bunch of BabeBee's and I'm not sure which engine it is. It turns freely and seems to have good compression, but I'm wondering if parts like pistons and cylinders can be swapped with other Cox engines? Also, what was their performance like, TeeDee or Reedie?

Bill S. (The other Bill)

BMatthews

I believe it's a Sportsman model that came out later. The Thermal hoppers had cast alloy crankcases but with the same kind of backplate and carb.

William Robison

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Bruce and Bill:

It is the "Space Hopper."

In 1959 and 1950, and for the early part of 1961 it was THE 1/2A speed engine. When the TeeDee came along the Space Hopper was no longer the hot engine, and production stopped.

The rarest version was the Space Hopper BB, that was the same size, but had a ball bearing crank. The plain bearing version was faster, so people tried the BB (I had one too) and went back to the plain bearing engine.

There were not a lot of them made, currently they are commanding a very high price from collectors.

Picture attached is one I still have, and its plane.

Bill.

William Robison

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Bill:

Just realized I didn't answer a large part of your question. All the parts will interchange with the other reedies, except the backplate and carb assy, and the crankcase. There were some made with a different length crankshaft, so if you have the odd one that's another part that wont interchange.

Overall, I wouldn't risk the engine in a plane, it has too much collector value. But so far as its power is concerned, the Space Hopper and Thermal Hopper were the strongest of the Cox reed engines.

Bill.

XJet

I had a Cox 0.15 (or was it an 0.9?) engine that looked like that (but bigger I guess). Does anyone remember what model was that then?

Ragwing

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There was a Sportsman .15 that looked like that engine--I had one-then sold it to finance some other engines

Derek

Tim Wiltse-RCU

Bill,

That is a nice looking Space Hopper you have there. It does have a newer cylinder on it though. They really run too! For what it's worth I am currently working on tooling to make a .020 sized engine based on it!!!


Later,
Tim

DICKEYBIRD

Dang ol' junk engines ain't worth nuthin'....you oughta just box 'em up and send 'em to me for proper disposal!

jessiej

[Picture attached is one I still have, and its plane.

Bill. ]

Thanks for posting those pictures. I was always fascinated by CL speed, but never got into it myself. Too esoteric for an ole country boy, but I loved to watch-and listen!

bsindel

William,

The turned down cylinder and glow head were custom work done for racing right? What kind of fuel mix did you use for racing?

Thanks everyone for the information on this little engine. It looks like I have found a little jewel in my box of cornflakes. Sorta like finding a Captain Midnight decoder ring in your box of wheaties (wish I'd kept one of those too). I love finding these things at garage sales.

Bill S. (The other Bill)

William Robison

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BillS:

Yes, it was a version just for c/l speed. If run on wooden mounts it would overheat if not run rich, the pan was used as a heat sink along with the top fin of the head being out in the breeze.

The glow head was also reshaped inside, turning the semi-spheric shape into a cone. When the TeeDee heads came along with the convex curved cone shape they were patterned after the earlier speed heads. And a lot easier to get. The TeeDee heads extended the Space Hopper's competition life a few months, the TeeDee heads were better than the more expensive custom heads.

The best commercial speed fuel was a mix called "This Is It." Subtitled "Hopped-up engine racing fuel." Think it was somewhere around 50 to 60 percent nitro. Another good one was "Franny's Fuel." Both were hard to find, but TII was a little more common.

In mixing our own we were among the first to use synthetics, the polyoxide oils worked fine and since they would burn in the cylinder thay also added a little power on their own. But. 100% polyoxide greatly shortened engine life if the needle was even slightly lean - regular lube wa 50-50 poly/castor. And one drop (or a little more) of cheap dish detergent to make the poly/castor/methanol/nitro components mix. Without the detergent the poly oil wouldn't mix. The best poly oil we found was "Castrollo," supplied by Wakefield (Castrol England) Oil Co. as a "Top" oil for automotive use.

The fuel itself was mainly methanol/nitro in varying ratios, with some amyl acetate, propylene oxide, and sometimes a little acetone.

Through the 1960 season if we wanted that litttle extra speed, the fuel got a squirt of tetranitromethane. Tetra, and all other corrosive fuels were outlawed starting with the 1961 season. And I agree completely with their illegality, they are far too dangerous for casual use.

Best ever speed on the plane I showed was in 1960, a hair over 102mph, using tetra in the fuel.

Bill.

DICKEYBIRD

Squeek, creak, screech, graunch (the sound of old rusty mental cogs slowly turning after years of disuse) Didn't some of the uhhh, connected (NASA) guys use a little anhydrous hydrazine to spice up the ol' fuel mix as well? That is until the AMA banned it. If memory serves, it was Titan rocket fuel! [X(]

I was probably 10 or 12 yrs. old and too young to be actually involved in u/c speed at the time but I'm pretty sure I read about it in M.A.N. Ahhh, the good ol' days!

William Robison

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Milton:

In my group was a fellow named Dave C... (wont complete the name, but some may know who he is) was an employee at the Redstone Arsenal, he was the source of most of our exotic additives.

Yes, hydrazine hydrate was also tried, and RFNA and WFNA among others. The hydrazine compounds worked well in the DynaJets, but I never heard of any good results in the piston engines.

Tetra was the best all-round, but it still had major disadvantages. Once mixed, the fuel went bad in about five minutes, if you were too slow getting off the ground planes were seen to explode in flight. And the wreckage had to be doused with water before it was safe to handle. Even if you made a successful flight the entire plane and engine, inside and out, had to be flushed before the combustion products ate it (and you, if careless) up.

Tetra is so poisonous that merely getting a whiff of its fumes can lay you out, a drop on your skin will put you in the hospital. It's unstable. let it get much above 60F in the bottle, the bottle will explode. Squirt it on the sunlit concrete, it will self ignite and burn on the ground.

Hydrazine hydrate is nasty also. RFNA and WFNA? Don't get close.

I hope I've said enough to discourage anyone trying any of these chemicals. If you are the least bit careless your funeral will be held shortly after your experiments.

Bill.

PS: WFNA and RFNA? White Fuming Nitric Acid and Red Fuming Nitric Acid. wr.

>>Edit to add R/WFNA PS>>

DICKEYBIRD

Dang, why does all the good stuff have to be either too expensive or bad for your health!

William Robison

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Milton:

Because "Safe" is not any where nearly as much fun.

Titan rocket fuel: unsymmetric dimethyl hydrazine and diethylene triamine. Known as a "Hypergolic" fuel, when they mix there's an automatic "Kablooey!"

Bill.

Andrew

Bill --

Thanks to you and RCU, I learned a new tidbit of information today (usually get one or two new ones a day here). I had never thought of the speed pans serving as heat sinks -- although it makes loads of sense -- just had thought they were to stiffen the fuselage and serve as skids for landing. Boy, do I feel dense at times.

Thanks,

the "other" Andrew

jessiej

I remember the exhaust of the speed jobs smelled pretty exotic- glad I didn't breath too deep.

Even on my relatively garden variety rat racers the heat sink effect of a magnesium pan was apparent. They got pretty toasty after a while.

jess

Jim Thomerson

A friend recently returned a Space Hopper I had loaned him about 1961 (bought in 59 or 60). I looked it over and decided the rod needed resetting. Discovered that the piston was in two parts, with a bottom piece holding the rod in. Swapped for a modern piston which fit nicely, put on a high compression head and ran it. Didn't tach it, but it sounded like it would run with a pretty good TD. Have to build something for it.

Jim