How big can you go with a Modified Fox 35?

[Mike Callas]

Hey guys,
I did a search for planes with a Fox 35 and came away with the impression it is for the Shoestring/Buster size planes.
With the latest mods is it suitable for a low to mid 500 sq" wing, mid 40oz plane?

I know there are better options, but I am building a Shark 35 and thought it might be a better match for classic/nostalgic combo.

OK, the real reason is there was a Fox 35 at the field yesterday and the sound reminded me of the plane I had when I was a lad (and Nixon was in office-2nd term).

Thanks

[John Fitzgerald]

I am flying a 42 ounce 42.5 inch wingspan 460 sq plane with a Fox .35 and it flies very well in 2-4 break mode.  The only modifications are stuffer back plate and tongue muffler.

[Bill Little]

The original Shark 35 was powered by a Fox .35, probably mostly stock.

There are much stronger engines available now so the larger planes that were originally flown with a Fox .35 are now powered by engines like OS .46LA, Aero Tiger ,36, Magnum .36XLS, etc. Even ST .46 and .G.51.  In the '60s planes near 50 oz. were powered by the Fox and winning NATS.

BIG Bear
RNMM/AMM

[Brett Buck]

Hey guys,
I did a search for planes with a Fox 35 and came away with the impression it is for the Shoestring/Buster size planes.
With the latest mods is it suitable for a low to mid 500 sq" wing, mid 40oz plane?

I know there are better options, but I am building a Shark 35 and thought it might be a better match for classic/nostalgic combo.

OK, the real reason is there was a Fox 35 at the field yesterday and the sound reminded me of the plane I had when I was a lad (and Nixon was in office-2nd term).

Thanks

   A whole lot of mid-40's , 565 square inch Green Box Noblers have been built and flown with bone-stock Fox 35s. I wouldn't go that big, given a clean sheet of paper, but hard to claim it doesn't work.

     Brett

[Marvin Denny]

  The Top Flight Nobler was designed around the Fox Stunt 35.  The nobler is about 550 Sq inch wing.  If built around 44-45 ounces, it is a very good performer.
  I have flown planes that had 600+ sq inch wing area and weighed 53 ounces and had very good performance from them (NOVI III) the Fox in that plane was quite old and had the Denny Hemi Head (similar to the Fox mfg  one) and a stuffer back plate .  Stock port timing and shaft timing but slightly modified shaft.
  Many of the engine rework specialists can and do get considerably more power from the venerable old fox Stunt 35 (and you can still get parts for them)

  Bigiron

[Bill Little]

I definitely listen to Marvin on the subject of Fox .35s!  He knows the deal.

BIG Bear
RNMM/AMM

[James Lee]

Marvin
I heard that Fox in that Novi...    Didn't sound like any fox I had ever heard!!!!         Seemed to pull more like a 60
Thanks
Jim 

[Brett Buck]

Marvin
I heard that Fox in that Novi...    Didn't sound like any fox I had ever heard!!!!         Seemed to pull more like a 60
Thanks
Jim 

  Vitamin "N" certainly doesn't hurt anything. 

   Brett

[Bill Little]

  Vitamin "N" certainly doesn't hurt anything. 

   Brett

Only up to about 30%....................

BIG Bear
RNMM/AMM

[Marvin Denny]

  Vitamin "N" certainly doesn't hurt anything. 

   Brett

  I do NOT subscribe to the DD mode of thinking.  The ONLY fuel I used in my engines was 7.5% Nitro, 28% oil  Oil content was 24%castor (Sig brand) and 4% Klotz.  While I did use many different props, the most consistant one was the APC 10 X 5.  Rev-up 10 X 6W was second .  Also---I ran mufflers too. (home made)  I called them "exhaust deflectors) as they didn't muffle much.

[PJ Rowland]

Anything will fly.. It comes down to defining what the point/purpose would be.

Sunday Park flier.. 600sq 60oz will fly with a Fox 35..... how good is debatable.

As we keep going on about on this forum its not all about the wing size, its the power up the front.

[Marvin Denny]

Anything will fly.. It comes down to defining what the point/purpose would be.

Sunday Park flier.. 600sq 60oz will fly with a Fox 35..... how good is debatable.

As we keep going on about on this forum its not all about the wing size, its the power up the front.

  If that isintended to be a slam , or an implication that  the NOVI III "wallowed" instead of "fly", I do not appreciate the slam.
  If you cannot get a fox 35 to run decently, please refrain from slamming others.

  THANK YOU

  Bigiron   aka Marvin Denny

[Tom Niebuhr]

Marvin knows more about running Foxes than almost everyone.

I am always amazed that more recent "experts" on the Fox .35 consistently knock its ability. We flew them for years. The only secret was the proper fuel and prop. The props will vary with the airplane but Marvin's recommendations are a guide line that will be close every time.

John D'Ottavio, in his heyday, flew Falcons and his Jerseyan at the unthinkable 58 oz range, and still won almost everywhere. I personally felt that an airplane in the 43 oz range was perfect.

Personally I have never had a bad Fox. I would recommend getting a tight one by special request from the factory. Then take your time and break it in properly.

Better yet, have Marvin work on the engine for you and you will be guaranteed to have a good one PROVIDED you run it as he recommends.

[Jim Thomerson]

It is nice when flying a Fox stunt 35 to have a fellow competitor ask if you are running a Supre Tigre 46.  I went to 11 x 5 props of my Fox 35's many years ago and never looked back.   

[Steve Fitton]

PJ, I've seen Marvin's Novi fly, that Fox is pretty stout

[Marvin Denny]

Marvin
I heard that Fox in that Novi...    Didn't sound like any fox I had ever heard!!!!         Seemed to pull more like a 60
Thanks
Jim 

Jim the Fox in the NOVI IV was even stronger and the plane was lighter at around 46 OZ..
 

  Bigiron

[jim ivey]

lets not forget the grand ghamp and his aries it was fox 35 powerd when i knew him about 60 years ago.  gma and his nobler. jim

[Bob Reeves]

Something else most are missing is the ability of the pilot to deal with power management. This is an art that has kinda got lost with today's power plants. Not sure Power management is the proper term but some of you guys understand what I'm talking about.

I think we use to be much more in tune with the airplane. Now I fly a Saito 62 and just stand in one spot knowing the airplane has the power to take it where ever I point it while wondering how I was ever able to fly my first Genisis back in the 70's with a ST46 on 68 foot lines.

[Bill Little]

Something else most are missing is the ability of the pilot to deal with power management. This is an art that has kinda got lost with today's power plants. Not sure Power management is the proper term but some of you guys understand what I'm talking about.

I think we use to be much more in tune with the airplane. Now I fly a Saito 62 and just stand in one spot knowing the airplane has the power to take it where ever I point it while wondering how I was ever able to fly my first Genisis back in the 70's with a ST46 on 68 foot lines.

Hi Bob,

A "little" towing here, a step back there, an extra lap whipping, all were things we used to have to do before the glut of power hit.

BIG Bear
RNMM/AMM

[Brett Buck]

Something else most are missing is the ability of the pilot to deal with power management. This is an art that has kinda got lost with today's power plants. Not sure Power management is the proper term but some of you guys understand what I'm talking about.

  "Energy management" is probably closer to what you mean. And you are absolutely right, it's a different ball game than it used to be. You can just plant your feet and drive it around in most conditions. Before about 1986 or so, that was just not possible most of the time, and those few times someone did get to that point, they won a lot of big contests.

   That's what drives me crazy about this sort of topic (i.e. Fox 35 performance and other vintage engines up to and including the ST46/60), not that there is anything so terrible about the old engines, but what you give up when you use them. Lots of people were masters of energy management and knowing exactly how to make the most of them, and flew them well (and many still could most of the time). But it was much more difficult than it needs to be. Current engines are absolutely marvels of performance, for most people there's no good reason to fiddle with vintage engines any more, other than nostalgia.

    Brett

[phil c]

More apropo to Mike's original post, the question should maybe be "what is the smallest size plane that a Fox 35 can fly and get similar power loading/wing loading compared to the 75 powered 600 inch planes?"  Weight in the 42-46 oz. range matches well with 60 ft. .015 lines.  Maybe 450-480 squares, 500 max, with slightly thinner airfoils, but using the same high lift concept airfoil design Al Rabe and Igor Burger came up with.  Maybe push the aspect ratio a bit to 5.75 for quicker corners.  Interestingly, that is only slightly smaller than Randy Smith's Vector 40 which is still a damned good flying plane.

[Marvin Denny]

  Phil, that isn't what the guy asked.

  Bigiron

[Mike Callas]

Thanks guys,
I appreciate all the info. As mentioned I have a Shark 35 about 50% done and was originally planning on using a Stalker 46 or LA 46. Then I heard an ol Fox 35 at the basin. It had a purple (?) head with the plug angled back ~ 30 deg. Un-muffled it had that staccato tommy gun beat in 4s which turned into a smooth 2S pulling up. The plane didn't vibrate much either. And of course that smell. Sounds like a modded Fox 35 might be the ticket.

My brother and I had a Buster with a Fox 35 in 73. We flew it at Glorietta park in Glendale. Funny how a sound or smell can trigger a memory.

Mike

[Brett Buck]

Thanks guys,
I appreciate all the info. As mentioned I have a Shark 35 about 50% done and was originally planning on using a Stalker 46 or LA 46. Then I heard an ol Fox 35 at the basin. It had a purple (?) head with the plug angled back ~ 30 deg. Un-muffled it had that staccato tommy gun beat in 4s which turned into a smooth 2S pulling up. The plane didn't vibrate much either. And of course that smell. Sounds like a modded Fox 35 might be the ticket.

    With an inverted mount, it will run just fine.

    Brett

[PJ Rowland]

Marvin & Steve..

I re-read all the posts - wondering what you both were going on about ;

I didnt even read YOUR 600sq 53 Oz Novi reference.

a: I havent seen it fly but Im sure if others say its amazing ,so be it.
b: My comment wasnt in reference to that plane or that line - my 600sq reference was a complete co-incidence
c: I was responding to "how big can you go" - it depends on performance.

I will offer an apology for misunderstanding & confusion sake.

[john e. holliday]

Well gents, I have two planes ready for VSC that are Fox powered.   

[Tom Niebuhr]

Brett has it right with "Energy Management". In the Fox days we had to work a little harder. Like most I am also spoiled with today's power. It is like having power steering. For modern stunt I wouldn't go back.

It is just that so many people under estimate what could done with the Fox in those days gone by. We used to laugh about waiting for line tension to come back at the end of the wingover legs. and don't forget having to whip it into the first loop of the 4 leaf clover. Nostalgic, yes, but I like today's power steering.

[Bob Reeves]

 "Energy Management" Yep that is the term I was looking for.. Thanks Brett.

[Brett Buck]

Brett has it right with "Energy Management". In the Fox days we had to work a little harder. Like most I am also spoiled with today's power. It is like having power steering. For modern stunt I wouldn't go back.

It is just that so many people under estimate what could done with the Fox in those days gone by. We used to laugh about waiting for line tension to come back at the end of the wingover legs. and don't forget having to whip it into the first loop of the 4 leaf clover. Nostalgic, yes, but I like today's power steering.

  The flip side of it is that modern engines have enabled a whole lot more people to be competitive than they would have otherwise. Only a relative few people had the necessary skill set to do all the nudging, pulling, etc, to get reliable top-rank flights back in the good old days and they are all legends - Billy, Bear, Ted, RJ, etc. Now, it's a different set of skills - probably not lesser skills, but different. Absent modern engines, I have to ask myself if *I* would have ever made it. Usually, if someone managed to get the rare perfect engine performance at the right time, they won.

     It's also a different approach. One of the things you used to do was fly a billion flights trying to learn and hone all these skills needed to "help" the airplane, and keep the engine running absolutely perfectly. They took a lot of flights to develop, and a lot of flights to keep peaked up. Now, while flying more (within reason) still doesn't hurt, you spend your time completely differently and much more efficiently. You *never* need to worry about having your engine run or getting enough power. So the "plant your feet and do the tricks" method works.

    Brett

[Steve Fitton]

The flip side of this is that I would much rather have a "wimpy" Fox 35 running a great stunt run vs the "trying to run a converted R/C engine and having a crappy run".  You can get good with a Fox powered plane.  You have no hope with a bad running R/C motored plane.

[Brett Buck]

The flip side of this is that I would much rather have a "wimpy" Fox 35 running a great stunt run vs the "trying to run a converted R/C engine and having a crappy run".  You can get good with a Fox powered plane.  You have no hope with a bad running R/C motored plane.

    Of course, all the modern engines that we are waxing poetic about ARE converted RC engines.  The problem with most poor runs with modern engines is either that someone is trying to run them like Foxes, either with or without modification. With modification, most of them are just as wimpy, without modification, you have to ignore most of the last 70 years of stunt lore to get them to work. Or you can get a modern engine that is designed and performs like a 50's engine with better metallurgy, like Tom Dixon advocates.

    Brett

[PJ Rowland]

" Absent modern engines, I have to ask myself if *I* would have ever made it. "


Come on now Brett.... Even back in the day you would have managed to run what we would have called a  "Buck-Fox .35" and done some serious Whipping on your own.

[Dennis Moritz]

Fox 35s are fine on Ringmasters. LA46s are much better on traditionally sized 40 stunt planes. Sorry but in my experience Fox 35s are all over the place in quality control. Poor bushing fit, prematurely worn bushings, over tight piston/liners. Over tight pistons can oval a pushrod, resist break in for a long time. Lately a skilled club member has started to regard new Foxes as Fox kits. Lapping in pistons, even replacing over clearance crank bushings. There are sweet running Foxes out of the box. But many seem to need TLC before they're ready. I have seen good running Foxes pull fairly light Orientals around nicely, good break. But LA46s running well are much more versatile and consistent, providing reserve power. Definitely an advantage.

[Larry Cunningham]

The first time I saw a flapped stunter fly with a Fox .35 in true 2/4 stunt mode, I was amazed at how slow it flew and half expected it would crash. Then I noticed just how well the 2/4 break worked! This was a Nobler sized ship, and it was capable of a respectable stunt pattern.

Latter day modified Fox .35s are truly smoother, sweet runners.

I started out with OS .40 FPs on the advice of Bill Melton, and later considered the OS .35 FP and bought one. I was surprised to find out that the .35 weighed more than the .40.. But the FPs were all noticeably heavier than Fox .35s. FWIW, the .35 version was popular as modified to turn large diameter props in a torquey mode. You can't really judge on raw displacement.

The Melton/Young {"High Altitude"} Roadrunner has a fairly large wing, and was designed specifically for an unmuffled Fox .35 (with shaft extension). Properly built, lightweight and with a properly broken in and well-treated Fox .35, the power was very adequate. Bill talked about a contest at Los Alamos, truly a high altitude site (~8000+'), where his Roadrunner flew well but some [heavier] west coast models, typically flown at much lower altitudes were falling out of their loops.. And at sea level, he said he could practically run his Fox .35 "4/8" mode to fly the pattern.

My point is that the models need to be light and well trimmed, and the Fox .35 needs to be "a good one", properly broken in and handled with TLC. It's a very competitive paradigm, which was the de facto standard setup for decades.

L.

"If people get a kick out of running down pedestrians, you have to let them do it." -Paul Jacobs, marketing director for a video game company

[Bill Little]

I doubt anyone will argue that the "modern" engines make flying a little bit easier.  Also, it is a matter of record that there were several very large models flown with the Fox .35 back in the day.  600+ sq.in. and over 50 oz., placing at the NATS.  Seen a Brodak Thunderbird flown very nicely by Derek Barry a coupe years ago.  Engine seemed to almost want to cut off at times, but just kept trucking along.

I love the new engines, they DO offer a lot to us that wasn't in the cards in the '60s.

BIG Bear
RNMM/AMM

[Leo Mehl]

I designed my Arctic Fox for the Fox 35 engine. Back in the sixties Gene Matheney and I knew what that engine would do and we decided on a peramitor on a 500 square inch wing an a plane weight of 40 oz. was ideal. My Arctic Fox was designed with that in mind. The only problem I have with the Fox 35 is cowling it in because of the short crankshaft which should have been made longer a long time ago(so much for nistalga). its timing is perfect for the 2-4 break but the engine lacks power considering todays engines but I always loved the way this engine ran so when got back into stunt again itook all this into consideration and built this plane that has a little less than 500 squares and weight in the 40 to 42 ounce size. Most people in the northwest have seen  <=this plane fly in some pretty awful weather conditions and I think it flys better than a Nobler because it is smaller and it lends itself to a better power curve.

[Bill Little]

The biggest Fox .35 plane I remember was Mario Rondenelli's Venus.  Quite large and it finished second at the NATS.

BIG Bear
RNMM/AMM

[Larry Cunningham]

Here's a good example of a Fox .35 powered Nobler, built by Mark Bowen from plans he got from George Aldrich. I remember Mark taking this model to a contest in Phoenix, where he competed in three classes with it and did well. It was one of his favorites.

A feature of many older classic ships is a thinner airfoil (say 18% or less of chord, ignoring flaps) which makes them more suitable for "modest" power. And of course, they must be lightweight. The weight margin is fairly small.

I remember Mark's Nobler went through a refinish, and afterward he said it never flew quite as well.

L.

"There's a pork chop in every can.." -Mark Bowen, on the nutritional value of beer