Klotz better than Castor...?

Does anyone have practical experience with either Benol, SuperTechniPlate, or R50? If it's not Hype, they all sound interesting... Duda in Austin, TX

For our applications castor oil is still the best lubricant. In some engines you need to use all castor. In some engines a 50-50 blend is recommended. In some it is optional. But with rare exception, you will never find a manufacturer recommending anything less than 50% castor. And the synthetics used by the major manufacturers are usually one of two or three different kinds. Castor has an enduring quality in that, even in high heat applications, it stays with the engine. In high heat, and under high stress, it turns to varnish and continues to protect the engine, while most synthetics will burn off. This is why the RC guys like the synthetics. No oil clean up afterwards. But if there is no oil coming out of the engine, you can guess what is happening inside the engine.

One of the problems in using castor is that if your engine does run hot you will get that varnish residue inside the engine. For some of the older iron piston engines this actually helps the fit and the seal. And should you run synthetic in that engine, it will clean it out (read the Byron's label) and you will lose the seal. On the other hand, with some of our modern engines, a varnish build up could lead to premature wear. For these applications a castor-synthetic mix will sometimes give you the best of both worlds. The castor will give you that extra quality of lubrication. The synthetic will keep the castor from leaving a varnish build up.

So, what I am trying to say is, stick with castor--at least a 50-50 blend--unless the manufacturer says you simply can't use it. And there are no "magic" oils for our purpose. If there were, the fuel suppliers would be using them (unless it was cost prohibitive, in which case it still might be cheaper for us to buy a new engine occasionally.)

And don't believe the hype that was spread (and still being spread) by Red Max. It is absolute garbage. The real moral of the story is, they got hold of some bad castor (cheap import) and can't get rid of it. Good castor is still available (and always has been) through all of the other manufacturers and Red Max's synthetic simply doesn't hold up as well as castor. We used to use their fuel. But I figure if they don't like their fuel any more, I don't, either. They just hurt themselves.

They state that it is "Degummed and extra fortified" which makes me think that there is something here other than just plain old castor oil. It doesn't sound like something we would normally use in our modeling appliacations.

Baker's AA, as I understand it, is simply the oil from the castor bean, pressed twice (the "AA" designation) and degummed. Nothing more. Nothing less. It is not "chemically extracted" as Red Max claims on their web site, although it is possible that some inferior castor oil from India or South America may be done this way, and, if that is what they got, that's their problem, not ours. I just won't use Red Max fuel any more figuring that if they aren't happy with it, I won't be, either. Surprisingly, they seem to be the only ones affected by this (of the major suppliers in the US). If you don't buy quality, you can't give quality.

I got tricked on this for a while, myself. I talked to their fuel guy, and got the "chemically extracted" and "pressed oil unavailable" story, along with an experiment to try. I got some of the their fuel, with only their synthetic oil. I also had them send some castor oil. The experiment they suggested was to add the oil and let sit, after which they claimed a white precipitate would form. I tried it, and sure enough, after a day or so, there was a bunch of white stuff in the bottom of the jug. Fair enough. Then I did the same experiement with SIG Castor Oil, and with Powermaster castor oil from the hobby shop. Lo and behold, nothing happened. No white stuff, ran fine. So, maybe it's some other fuel component in Red Max. I tried putting Red Max castor in some SIG fuel. Bunch of white stuff after a day or so. It really was bad castor oil. Bad RED MAX castor oil, others seemed fine.

Armed with this knowledge, I being a big-time rokit syentist, I went over to the standards lab during lunch hour, and had them through a little Red Max castor in the gas chromatograph. Wonder of wonders, there was some xylene present. Xylene is commonly used as an extraction agent to produce low-quality castor oil. Threw a little Sig oil in there, and even more wondrous, no xylene at all.

Conclusion: Guys at Red Max were largely telling the truth, the oil they had will not mix, seemingly was chemically extracted, and was unsuitable. The false part was that uncontaminated oil was unavaliable. When I asked them, instead of some mitigating argument, I got a sales pitch for their "proprietary" oil, and how we "Ukie guys" didn't know what we were talking about. This was unsatisfying.

The end result was that after a long period of good experiences, I didn't care to use Red Max anymore. I instead now use fuel from organizations that haven't tried to fool me. SIG, Powermaster, Byron, and others seem to have exactly what they claim. Despite the fact that "no one makes good castor oil anymore (circa 1995)", there seems to be no problem getting it.

In a previous life I was in the oil business (pronounced AWWL by most in it), and I came to believe strongly that at lower temps castor is good stuff, but, at high temps, synthetics are the plan. Castor burns. Good synthetics don't until we start seeing whisps of piston in the exhaust port.

It cost me a bunch to learn that, and the guy didn't answer what I asked, but I still find it useful?

See Ya

So, I suppose it depends on the engine. As a sort of standard (I mark fuel bottles with the formula in them), I use half synth half castor (I get mine from Castrol-a local guy carries it surprisingly).

It's actually the other way around. Synthetics (at least, the common alcohol soluble polyglycols used in model airplane fuel) will burn, while castor polymerizes into varnish. Castor will protect your engine in the case of a lean run, synthetics won't.

Ben L.
Klotz"

jd

Tony had been wanting to confirm the "29%" all-castor idea for a Fox engine (I think) that he acquired. I said if it needs to be broken in, go with the high oil content. Also, if it's a really old Fox or other iron-piston engine, avoid the synthetic to keep from dissolving out any castor varnish that is helping the old beastie's compression seal.

But I used 25% oil fuel (volume measurement) in Fox iron piston engines for 20 years without seeing excess wear to any of mine; now, let's admit that during that 20 years, I wasn't putting 5-6 flights a week on any single engine to really build up huge running times. I haven't "worn out" a sport or stunt type engine in maybe 25 years that wasn't damaged through use in racing or other unusual usage.

My combat engines, including various Fox and Super Tigre iron piston motors, were operated with 20% oil high-nitro fuels and I wanted speed/ power more than long life; the fuel mixes were mostly all- synthetic oil for those.

With the advent of new metallurgy for model engines, I am using 22% oil fuels, half castor, for ABC stuff.

K.