Not to knock our favorite engine, but....

Hmmm,

To each their own. And I mean that, but in all fairness to the Cox brand it can't hold a candle to a healthy reed and it's a rotary engine.

That sounds rough I know, but I compare apples to apples and the TD spanks it hard. I agree that it will fly most if not all OT 1/2A stunt planes, it just doesn't have the oomph required to stunt.

Mind you I have only tried one in flight and a couple on the bench. In flight it was adequate and needed a real open berth to get it to loop. I swapped it with a Babe Bee and I had enough power to do a basic loop without nursing it. It did however keep the plane aloft inverted.

So I guess what I am saying is for level flight and inverted it does have enough getup to get the job done. Apart from that it's lacking.

I hope that didn't come off hateful, it's just what I experienced for myself.

Ron

Cribbs74 wrote:Hmmm,

To each their own. And I mean that, but in all fairness to the Cox brand it can't hold a candle to a healthy reed and it's a rotary engine.

That sounds rough I know, but I compare apples to apples and the TD spanks it hard. I agree that it will fly most if not all OT 1/2A stunt planes, it just doesn't have the oomph required to stunt.

Mind you I have only tried one in flight and a couple on the bench. In flight it was adequate and needed a real open berth to get it to loop. I swapped it with a Babe Bee and I had enough power to do a basic loop without nursing it. It did however keep the plane aloft inverted.

So I guess what I am saying is for level flight and inverted it does have enough getup to get the job done. Apart from that it's lacking.

Reed or rotory hasnt anything to do with being a peformance engine or not, its the way the engine is timed. The Tee Dee is a performance design and the wen mac is not. Comparing a Tee Dee to a Wen Mac is not apples to apples.

HERETIC!!!!!! Get your pitchforks and your torches!!!! Burn the Witch!!!!

I hope I didnt come off hatefull too. I didnt mean it that way if I did! Dont burn me!

Well from what I've seen, this is one forum which diverges further from its main subject that any other, but that's great.    Sure, Cox engines is the main theme, but there's so much other cool stuff goes on here that we all end up far richer for what we are able to learn.  
I may not understand why someone likes one brand of engine (which I may not like) more than another, but it's no different than your favorite car   or favorite football team.    I may not see the same positives that you see, but that's what you like, so that's great.  
Cox achieved a lot of things that most other engine makers didn't achieve.  All credit to them for that.  Some think OK Cubs are dogs, but I like 'em.  I don't know why because most of mine won't run any good, but I just do.  Wen Macs produced millions of engines and an enormous number of models, so they must have done something right.  I respect what they were able to do, so I like them for that.  Higher rpm or greater stunting ability doesn't make something the best because we're all looking for slightly different things.  I've always driven Toyotas, and probably always will.  They're dull and not high performers, but that's not what I'm looking for.  I like to still be driving my Toyotas with 300K-400K on the clock, and they do, with a minimum of cost along the way.

So, to our O.P. it's great that you discovered something else (other than Coxs) which you enjoy and can get something positive out of.  If you want to win a tach race, then you might be barking up the wrong tree, but if you want to have fun, go for it.

Rod.

As they say - variety is the spice of life and I had never tried any .049/.051 other than Cox engines. A learning process for me. I had always discounted any other 1/2A engine, my bad.

Now I can't wait to try the Wen Mac Mark(s) I, II, Ok's, Spitzy's, Hollands, and Testors that I have accumulated since joining this forum. Doesn't mean I'm putting my Cox's on the shelf. I'm sure that my Musciano Cyclone will be wearing one soon.

Bob

It's the glow plug adapter head that lowers compression and affects top end performance. The later Wen Macs with glow head were decent engines, good sport engines for CL, FF and RC aircraft. Yes, they are not a Tee Dee, but still decent sport engines.

GallopingGhostler wrote:It's the glow plug adapter head that lowers compression and affects top end performance. The later Wen Macs with glow head were decent engines, good sport engines for CL, FF and RC aircraft. Yes, they are not a Tee Dee, but still decent sport engines.

Yes, I agree. Comparing the Wen's with a TD would be unfair. I have owned many TD's in the past.

Bob

Bill Atwood designed the Wasp 049 in 1950 and it ate every other 049 in sight until the Cox Thermal Hopper showed up. I don't have my notes with me, so I don't have exact dates. About 1953, Bill Atwood designed the Wen Mac engine, very much like the Wasp. When Bill Atwood and Bob Holland split up, Bill Atwood produced the Wasp as his Atwood. Later, with a GLOW HEAD, the Atwood became the Atwood Shriek and it was a powerhouse. Bob Holland did the Hornet with a big venturi and glow head and it was king of the hill. The Shriek and Hornet both outran the Thermal Hopper.

The Wen Mac and the Cox product engines were designed for easy starting and have enough power for the companies RTF planes and cars; not as competition engines.

In the late 50's Cox was trying to build an 010 sized engine. They couldn't get it done, so they hired an engineer with previous experience. His design for the .01 was successful and scaled up into the Tee Dee line. The engineer was Bill Atwood!

And as Gallopingghostler wrote, the glowhead is a key.

chevyiron420 wrote:

Cribbs74 wrote:Hmmm,

To each their own. And I mean that, but in all fairness to the Cox brand it can't hold a candle to a healthy reed and it's a rotary engine.

That sounds rough I know, but I compare apples to apples and the TD spanks it hard. I agree that it will fly most if not all OT 1/2A stunt planes, it just doesn't have the oomph required to stunt.

Mind you I have only tried one in flight and a couple on the bench. In flight it was adequate and needed a real open berth to get it to loop. I swapped it with a Babe Bee and I had enough power to do a basic loop without nursing it. It did however keep the plane aloft inverted.

So I guess what I am saying is for level flight and inverted it does have enough getup to get the job done. Apart from that it's lacking.

Reed or rotory hasnt anything to do with being a peformance engine or not, its the way the engine is timed. The Tee Dee is a performance design and the wen mac is not. Comparing a Tee Dee to a Wen Mac is not apples to apples.

I agree it's not a fair comparison either. I was expecting the WenMac to perform better than a Babe Bee and it does not on my opinion. Doesn't mean it's not any good just not for me.

I suppose that's why we have options!

Timing plays a role in performance, so does porting,compression, bearing surfaces,crank design etc.

That probably another topic. I guess in keeping with the theme of the original post, let us know how it works for you Bob! Glad you like it and hope to see it spinning circles soon.

Ron

Babe Bee and variants like the 8 cc tank version "Silver Bee" for mid 1960's war birds such as the Cox RTF Spitfire (had one back in 1965 or 1966) were IMO the standard sport engine for the RTF's. The Wen Mac was more or less comparable in performance, perhaps a little less. Key was the proper pitched and diameter prop. They are not barn burners. The longer venturi stack ensured good suction for fuel pickup.

Cox continued to improve performance of their engines to the point that Cox dominated the sport flier modeler scene. Key was the vastly improved glow head. The reedies were light weight, powerful, and cheap. My favorite is the 290 "Postage Stamp" engine of the late 1960's, which some used for half-A proto-speed I believe.

Later Testors .049 Red Head was the last of the series. IMO, with their improved glow head, it seemed to run just as well as the Babe Bees. The last of the series, 8000 reedie with integral plastic tank and RTF version known affectionately as the "Pipe Bomb" engine was a very well running engine to the extent that Peter Chinn applauded it.

Nonetheless, beauty is in the eye of the beholder. They have a place, just as much as the rest of the half-A's including the Babe Bee replacement Sure Start variant engines do, even though a good portion of RC modelers disdain these as toy engines. Only due to the influx of high powered electrics, do we see the return of the half-A sized planes now known as "Park Fliers".

As in any case with engines, with the proper prop, fuel mated to the correct airframe, these Wen Macs will continue to live on and amaze on-lookers as to how well they fly.

I like Rod's take on the subject. Any engine that won't run right is a "dog" until you can fix the problem! Any engine that does run right is useful when you mount it in the right model! Early full-scale aircraft, automobiles and boats had limited performance.. but they worked good enough. EDIT: You wouldn't want to use an OK Cub as a ducted-fan engine to power a fighter jet.. or need a Tee Dee .049 to power an early 1900's vintage scale model. This is a good discussion!

I noted some comments regarding glow-head vs. glow-plug head. This makes me really curious. Would the internal 1/4-32 thread-area of a plug cause some compression-loss? It's the one area in the combustion chamber that is not sealed. The plug itself uses a gasket.. but on every stroke, there's probably some loss on the up-stroke when the compression "bleeds" through this threaded area.. as opposed to hitting the "solid-wall" seal that a combination head/plug provides. On a small 1/4-1/2A engine, this probably makes a lot of difference. It makes me wonder if using a thread-sealer would improve performance?

I also wonder if the dis-similar metals in a separate-plug type head; sinks valuable needed heat away? The clamp-ring plugs/heads probably do a better job at holding heat in.. and again; they seal more like a glow-head.. rather than a glow-plug.

I just now finished and installed the Wen Mac in this AMF P-39 "partzer" model that I bought sans engine, bell crank, bell crank rod, control horn, belly pan, and front landing gear. An exercise in frustration. I have been fooling with this thing for weeks trying to get it right.



Most of the changes are internal. Tabs to keep the two half's aligned, fabricated control horn and rod, reworked pylons and front gear mount.



Even made "machine guns" out of tubing. Might paint them black in the future.



Only thing left to do is rig up some lines, gas it up and hope. But at least I know the engine will run properly.

Nice job Bob! You put a lot of love into your restorations. Even though this was originally an ARF.. you still had to "build it back up" to flying condition using good ol' ingenuity. I like the machine-guns the way they are!

Looks Good Bob!

Hope it flys well for you, do you have a closeup picture of that bellcrank? It's not something I have ever seen before.

P.S. Hope I didn't offend, I really need to learn to keep opinions to myself.

Cribbs74 wrote:Looks Good Bob! Hope it flys well for you, do you have a closeup picture of that bellcrank? It's not something I have ever seen before. P.S. Hope I didn't offend, I really need to learn to keep opinions to myself.

Ron, I don't think it a matter of offense, rather a position of personal preference. We all gravitate toward certain engines. If we all gravitated toward the same engine, it would be a boring world indeed.

Preferences dictate the style of airplanes we enjoy flying. Not all like hollow log airplanes, but to some they love the Dickens [tm] out of it. Some like competitive stunt fliers, and will approach the subject with their preferred powerplants and methodologies for ultimate stunt flying.

So all in all, we have a variety of interests and positions. Not any one's opinion is necessarily wrong or out of place. It is what we are, and we all have experiences to share in this great community.

Cribbs74 wrote:Looks Good Bob!

Hope it flys well for you, do you have a closeup picture of that bellcrank? It's not something I have ever seen before.

P.S. Hope I didn't offend, I really need to learn to keep opinions to myself.

The bell crank is different, quite a span at about 4". The belly pan has a stop (see picture) limiting the amount of up that you could dial in. I eliminated it in my reconstruction.



This was going to be my "learn how to do it" piece but it turned out good enough to use for flight purposes. Best olive drab shade that I had on hand is not a best match. Bell crank is out of a silver P-63, seller couldn't find the proper P-39 crank that he had on ebay, so he sent me this one. Later he found the olive drab crank. Just another problem that I had with this model.



BTW, no offence taken..ever. Differing opinions are what we all learn from. It would be rather dull if we all thought the same. It's a given that we all love the Cox engines.

Bob

Thanks Bob,

4" bellcrank!!!!

I have those in my PA stunters. I suppose it kept kids from over controlling. It's a different design, but quite clever.

Ron

While talking of Wen Mac engines, I decided to list the ones I have, just for interest sakes.

WEN MAC MODEL 1. 1952.
WEN MAC MK. II, MODEL 3- 1956.
WEN MAC MK. II, MODEL 8
WEN MAC MK. III, MODEL 4. 1961
WEN MAC MK. XII
WEN MAC MK. XIII
WEN MAC-NETZEBAND .049 PROTOTYPE- This is what I was told. It's basically an alloy cased Pipe Bomb- not sure it's any different to the Testors.
Just acquired a parts lot consisting of 4 MkII cases, a few cranks and some Testors bits.
Plus 7 Testors Pipe Bombs including front rotary valve models, McCoy #1 & #2 and 4 Testors/McCoy Red Heads on tank- mounts. That makes about 20 complete engine from the Wen Mac lineage. Don't really care if they're not powerful enough to fly- I can never build enough planes to fit them to.

Total engine collention numbers around 154 engines. From Pee Wees to an OS FS-60 open rocker, includes about a dozen diesels. Engines come from United States, Great Britain, Australia, Japan, Russia, China, Taiwan, India.

The multi-cultural Rod.

Inventories, you gotta love them.

Your's sent me scurrying to my meager Wen Mac stash to see just what I have. Turns out to be: 4 Mark I's?, 6 MkII's, 3 MkIII's, and a couple of AMF's.



In addition to any that might be on my engine wall:



I probably have more OK Cubs than any other engines, some day I will inventory them. Somehow a "pipe bomb" found it's way in there.



I really have grown quite fond of these Spitzy's though.



Some day, should the weather turn for the better I will separate the wheat from the chaff and find the runners among them.

I've been after a Spitzy for ages and finally got one a couple of months ago. Unfortunately missing the NVA so haven't been able to run it. Keep a lookout please folks.

Rod.

rsv1cox, Nice collection. I see you have the copper stunt tank and a Turbojet engine. I file engines waited for resto in the same way you do 7x7x7 Priority. Where in W Va are you? I'm just up the road in Beaver Falls PA. Do you get up to Brodak's?