"Bob" wrote >
The hideously evil thing about foaming is that it is gone a fraction of a second after the engine quits. You never will see it. It is like faith; you just have to know it is there!
Pretty much what I figured, but I had thought that there might be some residual bubbles in the high point in the carb line.
Question:
Due to the location and size of the tank I was using in the SS, I was using "foam rubber" (the same stuff used wrapping most receivers) around the tank. Due to the size of the opening in the former, I had to tightly wrap the foam around the tank, and then fairly tightly wrap the whole mess with 2" wide clear packing tape so that it would fit in the former. Would this have likely contributed? My normal useage is to gently wrap the tank, often bypassing the tape, and allow the formers to hold the foam around the tank (and within the former cavity).
Currently, during the present testing mode, I'm using a SPAD profile design, and the tank is rather gently wrapped with the same type foam, and is then held in place with a couple of plastic zip ties, and I am having the same problem, although I may be getting closer to half a tank prior to the sudden cessation of engine activity (same tank size as before, but new tank and fittings). I can accept trashing the engine and moving on, but it's now become a matter of principal (or stubbornness).
Whatever I do, I don't want a known problem engine to be the demise of the "new" SS that I was given from my old friend's estate (esp. as SS's are only available as ARF's or plan/scratch builds now). It's a fairly nice plane that he and I flew together a good bit, and he would want me flying it, and not using it as a hangar queen. I've been at this long enough that I rarely lose a plane to pilot error (but when I do, they're spectacular crashes). I'd just hate to lose this one through stupidity. He and I went back a long ways, and he treated me as a father in many ways, so there's a lot of sentiment involved. Probably why I'm prattling on so much about as inane a subject.
Realistically, I'll probably either rebuild his old OS if I can get parts for it, or shoehorn a GMS 32 into it; but I'm still going to try to figure out this ST. It's a great little engine when it's working, it just needs too many work breaks (sorta' like my employees).
Bob
I've been following your thread but your last account gave me a shiver. The RC gods must not be happy. I suggest a sacrifice. :) mk
On Sun, 15 Oct 2006 15:08:57 GMT, "MK" wrote in :
OH, my!
It's been years since anyone in the group called for a sacrifice!
In the old days, I think it had to be an Ugly Stik.
Dunno what the exchange rate is these days.
Marty
OK, I got the sphere mixed up with the ring.
Whaaaaat!?!?!? You're a Jesuit AND a college perfesser and you don't know? Oh, dear!!! ;-) Does this have anything to do with ST's no longer being Italian-made? Talk about blasphemy!!! Oy, vey!!!
On Sun, 15 Oct 2006 11:16:03 -0700, Geoff Sanders wrote in :
Pasta faggiole!
Marty
They're still taking trade-ins:
Thanks for the correction on the name of the ring.
Marty
I dont think MECOA is selling the GMS line other than what was still in stock. Parts for the .76 that Tower sells do not fit on the .76 that MECOA carried. Diff case, diff bearings, diff muffler, etc. They just cant compete costwise with the chinese makers is what the guy at MECOA told me a while back. Mostly the cost of casting. MECOA is not far from here so I bought my .76 at the shop itself. Also picked up my .32 parts there. Probably not possible to get those parts any longer.
On Sun, 15 Oct 2006 20:51:58 GMT, "Fubar of The HillPeople" wrote in :
The GMS engines came from the same plant that the Tower engines do. GMS is from "the chinese makers."
Maybe the factory is devoting all its production to Tower?
Given up on GMS?
Working on a different brand?
Marty
On Sun, 15 Oct 2006 11:16:03 -0700, Geoff Sanders wrote:
Hoo boy, looks like I've stepped into it now.
Being a simple hick from the boonies, with no club, only a couple of nelatively new RC'ers (that I more or less shanghaied so as to not always be flying alone), and definitely no nearby place of organized RC worship, I am in sore need of instruction from those of you here.
I realize that there is an entire pantheon of RC gods, rather than a single true RC god. I have had more than a passing familiarity with a few over the years. Such as the god "dammit" that controls the untimely placement of the feet of backwards-walking spectators -- seems to have a preference for wings over empennages. The god "oh-shit" that seems to have control of most things concerned with controlled powered flight, and the departure therefrom at the most inopportune moment. Of course there's the lesser god "oops". that appears to be the henchman of "of shit", but with generally less drastic outcomes for both the modeler and the model. Mustn't forget the god "uh-oh" that reigns supreme over the realm of radio-frequency communications. Yes, the one that ensures that a "charged" pack dies during your flight, mysteriously causes you to switch your computer radio to a different model during your flight, or blocks your signal entirely just because you flew near some wires that you believed only carried telephone service. He's the one that delights in YOUR acrobatics with the transmitter whilst your model flies whither it will, almost certainly coming to a bad end. He's also the one that makes certain your fail-safe settings will fail if they are needed and supposedly available. There's "not again" that seems to control most things encountered with IC engines, whether it has to do with mysteriously changing needle settings, or grabbing hot heads. He is also the patron saint of plastic surgeons, for those modelers that seem to be unable to keep their fingers out of the prop arc of a running engine. Then there are at least a couple of gods whose names I quake to even mention here that control the building process -- yes, "%&*@##" and his friends that assure that you build 2 left wing halves, or build the wing right-side up over the plans, when it was supposed to be the other way, or omit doing something in an area that becomes inaccessible later during the building process.
I feel certain that the pantheon is much larger, but without access to formal RC worship, these are the only gods that I recall becoming acquainted with over the years. If someone could help me to fill out the roster of gods, it would be much appreciated.
Now, as to intentional sacrifice. As has been already stated, I'm certain that the time is nigh for a sacrifice to be made to resurrect this baby ST engine. The fact that it is Italian and not Chinese will no doubt increase the conversion factor, but I am sorely lacking in understanding the conversion factor in the first place. Can appropriate recommendations be made? Must the sacrifice be planned in advance, or will the next sacrifice to come along be adequate? Must the sacrifice be virgin, or will one whose weight in epoxy equals or exceeds the weight of balsa be adequate?
Further, will the sacrifice need to be made to a specific god or group of gods, or will it require a convocation of the entire pantheon -- and how does one make certain the correct gods are in attendance in the first place?
(Sorry guys, this is what happens on a very rainy Sunday afternoon, when it's too nasty to even run a boat, if I were into boats).
Bob
On Sun, 15 Oct 2006 17:25:04 -0500, Bob wrote in :
"Everybody" has to go on the list, as in:
"Hey, Everybody, watch this!"
Not that I've attended the pagan rituals, you understand, but I seem to misremember that they called for an Ugly Stik to plunge headlong into the center of the field. How such things were arranged was known only to the initiates of the cult, of course.
If you have to ask, the initiates can't tell you. :o(
I'm enjoying a 5-day weekend in Buffalo, thanks to our first snowfall of the season. Last weekend, we were out in T-shirts at the field.
Marty The Big-8 hierarchies (comp, humanities, misc, news, rec, sci, soc, talk) are under new management. See
You crack me up. You can't plan the sacrifice. Just try your best to avoid it and it will happen. BTW, you might try being the first to truthfully describe the faulty engine on eBay.com and see what happens. I believe you and will not bid. You mentioned a sledge, if you haven't seen Philip Rawson's site it's worth a visit.
Yes, I had actually seen his site a year or two ago, and that's where the sledge idea came from..
Actually, although it goes against everything I try to do, you COULD plan the sacrifice. I have an old, early stick-style trainer that's as much epoxy as balsa. Unfortunately, I think it's a bit heavy for the ST .25. Wouldn't be too difficult to climb a few hundred feet, perform a full-power dive, and try to turn it into a post-hole digger. Only problem with that is that in similar crashes I've seen, the servos generallly get trashed as well as the receiver and battery -- not to mention the engine (other than today's rain, our dirt is normally about as hard as cement). But they DO make a very satisying (or sickening) ker-WHUMP. Only oroblem with this particular Stick is that due to its many repairs, it may well start shedding parts well before impact. It hasn't been flown in years, and isn't likely to be flown by me again. I just keep it around to give to any rank beginner that may want it, although they would be better served with a lighter aircraft.
Bob
Along the lines about foaming fuel: A few of us have been flying Accel Profile Katanas(too many of us!) and the tank is mounted on the side with zip-ties(ty-wraps?) Some did have a foaming problem from the zip-ties being too tight that was not apparent on the ground . I guess it makes sense that
3 points of the plane touching the Big Ball would dampen the vibration as opposed to being in the air. Anyway, better rubber aroound the tank and not-so-tight zip ties fixed that problem. mk
Ed mentioned the ol' Armor All trick too. That has to be seen to be believed, if you haven't tried it.
Take a fresh gallon of fuel and shake it. Observe the foam formed (even in the fuel that claims to have "anti-foaming" additives). Add two drops of Armor All. Shake again. Foam? Add another drop. Repeat as necessary. After a very small number of drops, foaming will just completely stop happening! It really works, and seems to have no ill effects. If you have the slightest hunch that foaming might be a problem in one of your models, try the Armor All treatment on your fuel and you'll eliminate foaming.
Good flying, desmobob
You must not use such an aircraft to appease these particular dieties. They require a pristine, museum quality kit such as those sold by Proctor Enterprises for more money than I make in a month.
You must then purchase either a $700.00 YS or Laser engine,
As an alternative, if you put the ST in the old wreck and it doesn't quit, you'll know that Ed Cregger's correct! But then, after seven minutes it will disintegrate in midair, go splat nose down and break the crankshaft as the gods watch with great glee. The choice is yours. :-P
Geoff
That's what happens when you don't have a proper place to worship the fickle gods of RC. And I thought it might be a simple as dancing naked around a bonfire of irreparable RC plane parts fueled with old glow fuel, with perhaps the hornets nest thrown in for good measure. Ah Well......
Bob
On Sun, 15 Oct 2006 23:32:20 -0500, Bob wrote in :
"One test is worth ten thousand expert opinions."
Let us know how it turns out, Bob. ;o)
Marty
-- The Big-8 hierarchies (comp, humanities, misc, news, rec, sci, soc, talk) are under new management. See
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I doubt there is anything wrong with the ST.25X. It is far more likely that you have a hole in your fuel tank pickup line, or the line just plain fell off. Of course, you could have had the fuel line and vent line confused.
I've been flying (blah-blah-blah-blah) years. It has been my experience that if the engine is adjusted properly to compensate for fuel burn off over time and the glow plug doesn't fail, when it quits it is a fuel tank problem. If not the previously listed problems, then fuel foaming, which, incidentally, most folks are not trained in detecting when they learn to fly. It used to be standard practice to teach newbies about this stuff. Now everyone doesn't want to be bothered. They just want to fly.
The ST.25X is a honking little engine. Such an engine is very likely to cause fuel foaming if the tank is insufficiently padded with soft, uncompressed (jammed in) real foam rubber. I would pull the old Tigre out, mount it up and have another go at it.
A good pilot is always prepared for a dead stick at any time, whether full size or a model.
If you think you had problems before, buy one of the latest engines with an oversized carburetor. (Pssst, that's all of them)
Ed Cregger
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