rcdude7

My Feedback: (264)

Can someone tell what a good prop size would to start with? This engine will be used in a TF flite streak. This will be my first C/L plane larger than 1/2A that I have flown. I would like to learn to fly stunt with this rig, however C/L is unheard of in my area, so I am pretty much on my own here. I am a experienced r/c pilot also and just want to try something new. Any other help getting started would be appreciated. Thanks

Mike

smcouch77

Hi mike. In my opinion the Max S .35 is one of the best stunt engines around. I use a wide blade 10-6 prop and 10% fuel. I get good consistent runs flight after flight. Good luck with Flite Streak.
Steve

downunder

Yep, they're a great little stunt engine but be careful what fuel you use in them. They really need 25% all castor for long life.

rcdude7

My Feedback: (264)

Not easy to find this mix in a shop anymore, however I have located a semi-local shop (1 hour drive) that sells this type of fuel, at least I won't have to order it and pay shipping and haz-mat costs.

greggles47

G'day Dude,

You could always add enough castor to bring whatever you have up to 25%.....or even make your own. If you have access to the components it's easy as can be. And then you KNOW for sure what went into it and the measurement protocol. Some fuel makers measure by weight rather than the more preferred by volume.

good luck.

Greggles

culver

If the local shop has Powermaster see if they will get some 10-11-11 for you, it's a blend of synthetic and castor 22% total or Sig champion 10% and add some castor to it.

rcdude7

My Feedback: (264)

I bought a case of Fox Duke's fuel today, 10% nitro, 20% castor, then I added 4oz S&W castor to each gallon, bringing it to 23%. I bench ran the engine for 5 or 6 minutes and it runs great on this fuel. The flite-streak is still in the works, but hope to have it ready in a week or so, I'm a slow builder.
I ran the engine with a new APC 10.5X4.5 prop, would this be good for initial flights to slow the plane, making it easier to learn? or is a 10X6 the prefered prop for stunt?

Thanks, Mike

Alan Hahn

I am not sure if you are referring to the TF ARF version or not, but if it is, I would warn you that the fuse is weaker than the original kit solid plank. The OS35S, while better than a Fox35 in smoothness, still may cause problems for the ARF nose. I would really recommend going to a smaller engine, like an FP20, 25, or LA25 or other equivalent. These have aluminum pistons and run smoother in general than a OS35S four stroking.
I run my Flite Streak ARF with a Fox15BB. I know, it has a steel piston, but it is considerably smaller, than a 35 size. My Arf tips the scale at 24oz (with some weight in the front to balance it near the leading edge) and flies great on 52 foot 00.012" lines.

If you don't have the Arf, then what I said doesn't apply.

rcdude7

My Feedback: (264)

It is the ARF that I am refering to. I do have a .15 max-s here, but I doubt it has the power of your fox and so is probably not up to the task. Is it worth while to strip the covering off the nose and maybe sheet it with some thin ply or something along those lines?

Mike

Alan Hahn

Maybe that might work. The basic fuse construction (sheeted stick frame the best that I understand without actually cutting into it) leaves a few "hollow" areas. One possibility would be to remove the covering from the nose doubler and the fuse just from the end of the doubler to roughly the point where the wing is thickest. Then add a balsa layer, the thickness of the front doubler back the where the covering was removed. Just trying to make a continuous layer here from the front back to the midwing area. Now add a thin sheet (1/32") of ply (or maybe fiberglass if you are into that) which goes over the original doubler and ties the balsa you just added to the original double. If you do this on both sides it should stiffen and toughen up the front end.
Kind of a PITA, I agree.
I do agree the OS15 max S may not be enough. But do you have an rc 20->25 size engine (like an FP)? You can always wire the carb open. In that case you want a 9-4 or 10-4 prop to run in "high rpm/low pitch" mode. Just an idea to avoid a rebuild!

Your 35S would be great in the ARF Nobler!

rjbranchii

Mike

Alan in right on for what folks are flying the flight streak arf's with. Most are using .25 size motors. "Back in the day".... when I was a young buck.... and the flight streak was what we were flying, we used .35's on them, 10X6 props and they went so fast you had to really keep up with them. Today, they are being flown alot slower and are much easier to fly. If you are going to use the OS .35 be very careful to run it rich. Never launch it in more than a 4 cycle with occaisional 2 cycle breaks. It will be about 75 to 8500 rpm. If it breaks into a 2 cycle, do not do any maneuvering. The heat can kill the motor and let it land and cool. Keep the nitro 10% or lower. Prop wise, keep the diameter no higher than 4 inches and you will be fine. Castor oil and total oil package 22 to 25% is key.

Hi Alan! Still got some grease under the nails I see.

Bob Branch

hothandle

I believe he must have ment 4inch pitch, not diameter. Even a 4inch pitch seems rather small however, I would probably go with a 10/5, and needle it to where ilt was in a 4 cycle with occasional 2 cycle bursts. By all means use lots of Caster, the rod is a weak point and a lean run will ruin the piston/liner fit.

smcouch77

This is a very interesting thread. I have a 22 year old OS 35 Max S in a 22 year old Nobler. I have always used synthetic blends at about 15% to 18% oil. This combo has flown smoothly and consistently all these years. I use SIG 25% Castor in my fox engine. It won't run on anything else. So I tried some in my OS. It ran very rough and I couldn't get a good 4-2 break. You guys that are using the pure castor in your OS engines might want to try a synthetic blend. You'll like it.
Steve

rjbranchii

Hothandle

You are right, I ment 4 inch pitch. With 5 inch the plane will be too fast and the motor will tend to overspeed into the lean end. I used to compete with full stunters (550 to 600 sq inches) scratch builds with Rev Up 10X6 EW's. But when a lean run hit I was careful to not let it out of level flight so I didn't ruiin the piston/sleeve. These were full bodied planes in the low 40 ounce range. The profile flight streak just doesn't need anywhere near that kind of power and if you give the motor half a chance it will go zoom, especially in the wind. One of the real suprises to me when I returned to stunt last year after about 20 years away was that most everyone is flying with 3 to 4 inch pitch props. They have done alot to solve the overspeeding hot lean run issue. Not completly, but alot better and especially in the wind where they would really take off in maneuvers.

Fuel wise, blends of synthetic and castor are what I was talking about. A 50% ratio of each and at least 22% oil total. I agree, modern motors don't need pure castor like the old fox's did. Interesting aside, in ducted fan motors we want castor in there for the same reason, to dissapate heat and still be there to lube at the high temps we get turning 22 to 28000 rpms in .90 range motors. There are some custom stunt motors (Ro Jett in particular) that are designed around an all synthetic fuel. Randy Smith's PA custom stunt motors are recommended for a blend fuel. Most stunt fliers today use a blend.

Bob Branch

gcb

If your iron/steel engine has a lot of time on it, and you have been using all castor lube, it may be "over the hill" and maintaining compression via a castor varnish. This varnish resides in to pores of the iron piston. A nice run of all or part synthetic can clean the engine of this seal and leave you with little compression.

Running all castor will get the seal back by rebuilding it.

Conversely, if you have been running all or part synthetic in an iron/steel setup and your engine is near the end of its useful life, sometimes you can regain some compression by switching to all castor. Remember Duke's ads for Fox Superfuel before ABC?

Castor is not required for an iron/steel as long as you needle it correctly. Castor may save your engine if you get some excessively lean runs.

BTW, the varnish seal is only for iron/steel, the high silicon aluminum pistons are not porous.

George

rcdude7

My Feedback: (264)

This engine does not have the dark brown varnished piston yet and has very good compression and a tight fitted connecting rod. The cyl liner still has most of its cross hatch hone marks still there also. I think it is safe to say that this engine never had much running despite its age. I'm lucky to have found this one cheap on ebay that was properly cared for. I have another that was a ebay engine also and the rod fit is very loose, probably a victim of synt or part synth mix fuel. I am trying to locate a rod for it. BTW, I found that a Enya .29-35III rod has the same size crank pin and wrist pin size, only it's about .014" shorter in length. If I could lower the sleeve by that much, I could use it, and it has a bronze bushing in the lower end too.

Mike

049flyer

My Feedback: (18)

I have a Top Flite Flight Streak ARF with a old fox 25 bushing engine flying on 60 ft lines, .018 diameter. The plane is way too fast even at a very rich 2 stroke running a 9 x 5 prop. A rich 4 stoke is better but watch out for the end of the tank cause it will become a rat racer for about 5 laps before the engine quits. Next time I fly it I'm going to try an APC 10 x 3 prop in an attempt to fly in a constant rich 2 stroke and still get reasonable lap times.

By the way the landing gear on this plane is terrible!! Mine nearly twisted off on the first landing and the tire crumbled at the same time. Replace the landing gear and tire before you fly it.

DO NOT BALANCE THIS PLANE WHERE SUGGESTED IN THE MANUAL. The manual lists a CG way too far aft for normal flying. The manual lists the CG location at the spar but I suggest that you balance it about midway between the spar and leading edge.

Otherwise a great flying plane for $50.00.

gcb

2fast,

You might try a uniflow tank if you are not already using one.

You might also try .015x60'ines to compare handling.

I'm guessing that you are referring to the 4-bolt backplate Fox .25. Those are really good engines IMHO. You might consider trying a 9x4 also.

Sounds like you are having a good time with your setup ('cept for them 5 laps ).

George

jackpower123

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rcdude7

My Feedback: (264)

Here is my flitestreak ARF before its first flight. On the advice of folks here, I found a great deal on a used .25fp listed in the RCU market place and installed it instead of the old OS MAX-S .35 engine. I have made a few mods to the plane enhancing durability while trying to keep the added weight to a minimum. I re-did the leadouts and attached the elev control rod using a ball link. This elininated a lot of slop and makes the linkage operate smoothly. Mounted the engine on plates I cut from some scrap .062" 2024 t-3 aluminum, made new LG from same. On the new LG I'm using a sullivan 2.25" wheel, and a 10X4" apc prop up front. I went with dubro pinned nylon hinges in the elev in instead of the questionable CA hinges included in the kit. I have some 60' .015" lines and the CG is about 1.5" back from the LE for starters. I will maiden this rig sunday if the wind is light.

cutaway

I won a couple of shelves full of Slow Combat trophies flying Streaks with a 36X's in'em. Its a very capable plane.

When you start getting used to it, start moving the CG back a tad and it'll find a whole new realm of performance.

da Rock

rcdude7,
You asked a question about props back when you were going to use the 35. The answer to, "what prop should I use" should always be, "which props (plural) should I try", and works for this engine just like for the 35.

Always take a couple of different props when trying out a new airplane. And try different diameters especially. And in your case, a 10" diameter prop just might be too much for a 25. It might be ok, but take a 9x6 since it's often a good one on the smaller engines. It'll save you a flying outing to have the props to test when you're out the first trip. It's dead simple to try different props, and it's really almost always worthwhile with any new airplane.

Lot's of times, advice about props is too narrow. Too many of us think there is going to be just one prop that works for each engine. You'll hear, "the only prop for that engine is......" way more often than you should. If you start testing different ones you'll find out for yourself the best one for that airplane/engine plus you'll learn just how many different props are "best for that engine".

rcdude7

My Feedback: (264)

*FLITE STREAK UPDATE*

My first two flights on the OS .25FP powered flitesreak ARF are complete and the plane is undamaged thusfar

For my first flight I set the engine to run at a fast fourcycle, breaking back and forth into a rich two cycle. The wind direction was right and take off was smooth and easy, the engine instantly went into a rich two cycyle and the plane flew fast and smooth until the tank was depleted and I pulled off a faily smooth landing.
For my second flight I missed the fact that the wind had reversed direction. Upon takeoff the lines went slack and the plane went into a verticle climb, lines still slack and me backpedaling like mad to tighten them up. By the time I did regain control, the plane was 3/4 through a huge loop and heading towards terra-firma, I pulled into level flight at about three feet off the deck, Wheeew............Flew circles till fuel depleted and smooth landing.

After that I packed it up and went home...............

I learned that this little engine has no shortage of power and the plane is still very fast, even with a 10X4 APC prop. I felt as if the plane was going too fast to attempt any stunts, even a simple loop. Or maybe I'm just a chicken at this point having never before flew C/L larger than 1/2A.
I learned to pay closer attention to wind direction and wait for a calmer day. I am also a R/C pilot and would have flown on a day like this with no problem.
I learned I have a looong way to go before I can fly stunts like some of those guys I see on the YOUTUBE videos. Also, while having R/C pilot skills helps some, this is a different ball game altogether.

This was fun and I will be looking forward to my next outing.

Mike

cutaway

I guarantee the plane is not too fast. You're just not used to it yet. With a 10x4 prop on any motor, you're not even close to how rockin a Flite Streak can be.

I can fly the whole pattern using an old Nemesis II fast combat rig with a pressurized G21.35, 40% nitro and an 8x8 prop. It'll be a pretty loosy-goosy pattern, but even at 110+mph, its possible to do it. Can't afford any brain farts on a flight like that though ;->

Drop a ST .35 in that Flite Streak with a 9x7, 25% nitro and a pressure tank and it'll blow your mind ;->