GallopingGhostler

Horace, I think there are exciting things coming to CL in the upcoming years. I'm thinking there may be a resurgence in CL flying, as the trend seems to be further local government restrictions on RC flights because of onboard photographic equipment. I don't see how someone can arrest someone for participating in "tethered flight", although anything foolish can be possible. Electric flight is adding new dimensions to flight with new electronic timers for ESC's from places like RSM Distribution. Now, the impediments to multiengine aircraft can be overcome by having all motors started at the same time and stopped the same time. No longer does one have to ensure that the trailing engine has enough power to continue sustained flight with the outboard running out.

JKinTX

I'm not being pickey at all Chief. It works on some engines and conditions, not on others. The larger the displacement is, the less critical the ratios are for general "sport" use. Shrink down to K&B Infant Torpedo .020 or Cox .010 size and it quickly becomes VERY critical.
The oil goes flying all over the combustion space and the plug, and guess what, it will bond to the platinum glow plug element far faster and better than the alcohol will- result fouled or dead glow plugs.

JAK

JKinTX

Iwould tend to agree with this.

JK

Dwayne

Sorry not to be picky myself but who said anything about small stuff, the OP was about a Fox .35 and Torpedo 29 and 19, just add 12 oz. of castor to a jug of fuel and go have fun. The end.

gcb

Thanks JAK, I have a K&B Infant and a few TD .010's and I had not considered that.

George

JKinTX

Nope!
It doesn't work that way. You think there is no difference at all in the running character and such between a GH Torp .29 or a .19 and a Fox .35 then you are VERYgreatly mistaken.
I have a whole bunch of Torps, and Foxies as well as others. Some 10 of the GH .35 Torps alone, and I know them quite well. ALL engines are individuals and no two are exactly alike- similar maybe, but the same no.
The Torp .29 and .32 are close but not the same, and there is a difference between the .19s and .15s as well. All of which tells me you don't know what you are talking about, but I already knew that.

JK

JKinTX

You are welcome sir. It will kill your plugs deader than a concrete lawn jockey and once it is on there, there is no way to get it off that I know of that won'tdestroy any seals on the plug at the element or whereverthe element fixing is.

JK

Dwayne

How much oil are you adding? For my 1/2a stuff I've been using Basher 20% nitro car fuel that has 16% oil, I add 1.5 oz. of castor to one quart which brings the oil up to 20%, it works great and I have never experienced a fouled plug.

JKinTX

You are the most fortunateof men!You are in Canada, correct? Try that down here in SE Texas in the heat and humidity (or cold and humid) we have here and it won't work.

GallopingGhostler

Then may I ask, JKinTX, for these little 1/2-A critters, what is your honest opinion based on your experiences what a person should use for their fuel?

JKinTX

It completely depends on where you live, the engine in question, and the operating conditions at the time. The old schoollittle guys usuallyhave fragile internals and in most cases today, replacement parts or service is non-existant so be guided by that.
The castor content needs generallyto behigher inhot weather than in cold, the nitro ratio can change alsoto suit.
That said, back before synthetic oils, we ran the Cox fuel out of the can here locally and we had more blown (fouled) plugs here in theSummer when it got above acertain temp/humidity level than at any other time. Today, I would drop the castor off atad andrun slightly more synthetic.
Best is mix your own. In most cases, you can have it mixed for you by one of the custom blend dudes.
Iused to run some of my OK Cubs on FAI fuel- in cool weather- but performance wasn't great, even for a Cub.

GallopingGhostler

Back in the late 1970's, I was running K&B, Duke's, and to a much lesser degree the Cox fuels, all with the higher nitro content (15% - 25%). They worked satisfactorily in the reed valve .049's. Since they were Castor based, after so many flights, I had to devarnish the cylinders. Didn't have a problem with plug fouling, but then I always peaked out the engines with the nose of the plane pointed 45% up.

Now that I am retired, I have acquired some old legacy baffle piston engines, Enya, OS Max, OK Cub, AC Gilbert, Fox, McCoy, K&B and etc. Also have a bunch of Coxes with the ball and socket con rods and aluminum crankcase plain bearings. Those are the ones I'm modifying the oil content of the modern fuels up to standards, mix for small ones, another for larger.

JKinTX

That is the best way to go!
Ionce had a McCoy .35 that was a redhead that turned into a brunette and that was on Fox Superfuel!
Engine all wrong crummy fits- way too tight.

downunder

I won't comment too much on the .049's because I've only ever run 3 different Cox's on the test stand with FAI fuel just to see how they'd run. All gave one flick starts and ran perfectly, certainly good enough for sport flying. The smallest engine I've used was an ETA 29, starting back in about '58, then progressing through Frog 500, K&B Stallion, OS Max-III 35, Enya 35, Merco 35 (where I began competitive stunt flying), Enya 45, ST G51, Stalker 61, OS 40/46VF, Irvine 40RLS, Stas's 42RE and now Enya 61RE. Everything up to the G51 was run with 75/25 all castor and from the Stalker on were run on 80/20 all castor except the Stas's which has an iron piston. I'm not counting the multitude of engines I've only run on the test stand where I always use 75/25 fuel. I've never used or found any need for nitro.

Essentially, any engine with an iron piston should use a minimum of 25% oil, preferably castor, but the best way to find out how much oil an engine needs is to start off with a high oil content and check the head temp (using a thermocouple, not infrared) then reduce the oil content a little and recheck the temp. Keep doing this until the temp starts to rise and go back to the previous oil content. Even this isn't a guarantee though because something like an OS Max-S will run fine (as far as head temp goes) with 20% oil but the rod needs at least 25% if it's to survive. It's good to keep in mind that too much oil has never ruined an engine while too little will kill it .

Larger engines can use less oil because cylinder bore area (where oil is needed) increases at a much slower rate than cylinder swept volume (which is what determines how much oil is drawn in).

iskandar taib

My Feedback: (5)

I heard that one years ago, but it isn't quite true (at least, not any more):

http://www.alibaba.com/trade/search?...t=nitromethane

Iskandar

GallopingGhostler

iskandar, perhaps a better wording would be what is available in USA for USA customers. To eliminate other countries, I went to advance search with exact wording (for some reason would bring up everything including the kitchen sink if not), it brought up two suppliers, one in US and another in US who supplies a China product.

Dwayne

Holy cow Isky you're alive...lol Miss the old forum. ))

Dwayne

I found this post over on Stuka Stunt that everyone might find interesting.
http://www.clstunt.com/htdocs/dc/dcb...d=383639&page=

JKinTX

Me too! And the Krylon Paint People and "My 1988 Honda Accrod clatters when I accelrat" dude!

John

JKinTX

"It's good to keep in mind that too much oil has never ruined an engine while too little will kill it .

Larger engines can use less oil because cylinder bore area (where oil is needed) increases at a much slower rate than cylinder swept volume (which is what determines how much oil is drawn in)".

Yep!. But be prepared to replace/clean plugs as needed.
Watch out for Fox .59 as the only upper cylinder seal is the gasket on a flat surface- push it too hard and POOF!

gcb

Don't forget the submarine guy and the gent who wanted to rebuild his truck diesel...those were the days.

George