Stuka Stunt Main Forum · 31 of 31 known posts recovered
See Ya
Peabody
Dennis,
I will be surprised if your various certificates, coupons, etc. will prove to be additive. I don't know, but suspect they'll tell ya, "Pick *one,* boy!"
From what I have heard, Chinese ST51s (is that funny, or what!?) run fine. As in no better or worse than units previously made in Italy.
Yep, ringed engine. If there is some gap between ends of ring (referred to as end-gap, amazingly enough), no problem. If not, big problem.
In any case, you need to disassemble engine, install just the ring in liner, see if you've got desired .002 to .004 gap. If not, get out the file.
Oh, yeah. When you order the engine, order at least one spare ring. Think well of me when it becomes clear to you as to why I might offer this advice.
Rev-Up 11-6EW is generally a really good prop. Also really hard to find.
I think SIG 10% Champion fuel will be fine, although some spice it up with another one or two percent of castor.
As to the model, we don't see many Cardinals out here, but I used ST51s in both a variant of the SIG Magnum (Mutant Magnum, Helmick now owns it) and my first Impact. Plenty of power.
Dan
D
D
Typical ringed engine "comes in" nicely and quickly. No weirdness.
Dan
Noticed the prices of ST .51 in Tower were about $119 or $129. I didn't see the $79 price tag. Is that a special? Mike's Models in OKC sells them for $79.95 (RC). He thinks the C/L one would be $10 more. What a great price. Make sure you buy the C/L one as it has a different liner than the R/C.
Edit: Props to try on the G.51 are APC 12-5, possibly cut to 11.5", or Graupner 11-6.
Robert
Leonard,
Since you are an advocate of lotsa power, I'm curious how would respond to this. I know you're not an LA fan, but what would you recommend here? Extra head shims, smaller venturi, different prop? Stuka .53?
I'm debating CardARF engines with myself, and neither one of us is winning. 
Thanks,
Split Personality in Santa Clara
Apologies, but somehow I overlooked your mention of the ST51 going on a profile Cardinal. For some reason I blew through your post, mention of the 51 lead me to think we're talking built-up Cardinal. Apologies...
Some of these guys cautioning against too much motor and too much weight may well have a point.
Tell ya what, Heavy Stunt has a kit-built profile Cardinal I have seen fly a couple times, especially noteworthy as last time out I put him on the trailer in Expert P-40. Using (read: borrowing back momentarily) the "Dirtmobile", ARF Flite Streak with 20FP for power. Snicker, snicker...
I'd do two things: 1) Fit model with sheet aluminum gear; the wire gear seems to flop around too much on landing and take-off; 2) Install a stock Magnum 36XL.
We can probably get Helmick to prompt Mike Haverly into providing much more complete information, especially as he has now got his Oriental/Magnum 36 quite nicely sorted.
Besides, do you really want to be flying a profile on .018s??!! C'mon...!
Dan
Gosh, I've been watching this post and you Dan are really the first one to really take a stand on this combination. Personally I think it's absurd. At the recent Golden State Stunt Contest I watched ST 51's pull full size 64 oz. stunters thru the pattern. Not saying it can't be done but the weight of the motor and the power will make this very interesting. I would like to see this, I think it will be entertaining to say the least. Grins
Steve The lomein pizza ST51 ( king of take out) just seems so intriguing and big time cheap for what it is. A mythic power plant perhaps such as other ST engines like the 46 and 60 and the LA46 is becoming. Seeing my newly baptized (sort of) Fancherized Twister fly at Mach 1 when my FP35 broke full lean made we wonder about the overpowering thing. When tamed the FP40 and 35 do a great job on a Twister, but power for power sake. Well, no. Not so good an idea all the time. Can the ST51 be tamed enough to pull the profile Cardinal at stunt speed?
As far as the Magnum36XL none of us have run it in Philly, yet. I've read a lot of the positives. Definitely worth a shot in the future on something. The Cardinal seems a lot more airplane than a Twister. The extra wing area and airfoil thickness (I believe this is so) likes more power.
Ahh what the h#ll I've got two ARF Cardinals... I think I'll... Imagine thinking like this about a hobby... a sport... a way of... fun isn't it?
D
Take my word for it. The Magnum 36 XLS will pull the feathers off that Cardinal. I have seen them in action and there is nothing to worry about, plus you will not have the balance problem you would have with the ST 51. The ST 51 is a great engine but is for the bigger planes.
Can the ST51 be tamed enough to pull the profile Cardinal at stunt speed?..... Why would you want to?. The best motors for this plane weigh less, cost less and use less fuel and will balance the plane better as the Cardinal was designed around these motors. Why take a good design and create problems for yourself. The LA 46 is stone reliable, available etc. etc. etc. Good luck
>Guess I've got that contrarian gene, so, I WANT to try something else. (Would you know anything about that?)
>As far as the Magnum36XL none of us have run it in Philly, yet. I've read a lot of the positives. Definitely worth a shot in the future on something.
>Ahh what the h#ll I've got two ARF Cardinals... I think I'll... Imagine thinking like this about a hobby... a sport... a way of... fun isn't it?
D
Dennis,
In snipping your response down a bit, I believe we have the answer. And you supplied it!
Being contrary can be a *good* thing, and you *want* to try something else, just about anything else would be my guess, seeing as how you lean toward ST51.
You then go on to say that no one in the Philly area has run a 36XL.
Excuse me for saying so, but I believe latter engine meets your stated criteria.
And they really work! Were I to be building, oops, assembling a Brodak profile Cardinal, my *first* choice would be the 36XL. For pretty much the same reasons you cite, plus you'll look like a visionary when the package comes together.
Dan
Watching a friends Twister today pulled around by well behaved snarling crackling FP40 beast, I realized ##### that little plane's really moving. Definitely in the high 4 second area, if that, not a 5 second lap by any means. For once the winds were quieted at our field just nasty and tricky way bellow gale force. Perhaps our enthusiasm for the fire breathing FP40s are due to the zeus' chronic stomach ache near the Delaware River in Neshaminy Park. Also for once the LA25 on my ARF Streak seemed on the powerful side as opposed to moderate and balanced. Adjustments, adjustments. Dense cold air and relative calmness. Could almost get my mind around the idea of an FP20 on a light streak. Typical conditions at our field, where it is usually on the rough and nasty side, favor lotsa power and high side stunt speed.
(Note: looking like a visionary in any way would blow my comfortable clownish routine. Hate to have anyone look to me for advice. Where's the chuckle in that.)
D
Leonard neumann has venturi's for the 36 XLS. I bought a couple from him [email protected] Bill Little has experience with this motor and has given input in the passed.
Current 36XL is the one. I refer to it as a "squarehead" engine to differentiate between older 36.
I simply made a reducer for case so I could use the bags of O.S. venturis laying around. Little J-B Weld, you're good to go.
Beyond that we need better input. My own 36 has been run on stand, never flown. I simply will not make specific suggestions as to a setup which is unknown to me.
That's why we need to hear from Keith Varley, although he is using the PTG setup, complete with pipe; Mike Haverly who is very successfully using one of these engines in an Oriental and with a tongue muffler; maybe even Derek Moran, although his model is still abuilding and he will be using a pipe as well.
From what I have seen, standing *outside* the circle, Mike doesn't even try for a 4-2-4 break, level flight it's set to a "wet" two-stroke. I *think* Mike has mentioned use of a .250-bore venturi; I have no idea what NVA he is using.
Dan
Just what is the tipoff that the bearings have gone bad, other than total destruction (i.e., crunching)? Leo Mehl told me he had a shaft run on his XL .53 and after, the fuel economy was terrible. New bearings fixed that, and the engine returned to it's previous good manners. Other clues? 
Steve
D
When the character of a man is not clear to you, look at his friends.
Japanese Proverb
Our main experience is with a '59 Ares of Aaron's. It is up to about 39-40 oz. now.
We set it up like PTG suggests, and used a venturi from an OS 32F that had been used in the plane from the beginning. The OS 32F venturi is a perfect fit. Have no clue as to the size but I believe it is in the .250-.255 range. NVA is a Randy Smith item.
The ship had immediate improvement, esp. in the overheads and braking on the down side of manuevers. Aaron won his first outing with this set up at Marietta last year. The plane had two flights on the set up before the meet.
We used a Bolly 10 1/2-4 3 bld repitched a little bit under 4, and set it in a good 2 cycle, backed off from a peak setting. The ship will fly extremely well at 5.3-5.4 on 62' E-E .015s. With the OS 32F it wasn't happy over 5.1.
There was absolutely nothing done to the engine other than adding a venturi/NVA, tongue muffler, and bench running it.
It doesn't have the same run as an Aero Tiger 36 (which I really like), the Magnum doesn't 4-2 it runs very much like a pipe motor.
A very nice set up for not much money, I have no doubts that it would fly a Cardinal ARF very nicely.
Bill <><
When the character of a man is not clear to you, look at his friends.
Japanese Proverb
Okay, I sicced the best guys on ya and they told you how to run the Magnum 36XL. We expect (almost) immediate and positive results.
And you go off the res just one more time, I will be suggesting a Saito 82 for that poor ol' profile Cardinal of yours and we'll just let ya twist in the wind from that point on...
As to Steve's question about bearings in the Magnum 36XL, I can respond pretty accurately as I was witness to this very act. *And* had it wrong until the engine was simply toast.
First, from what I have seen this is not a common problem. Yes, it has happened, but only the cautious will be replacing stock bearing set. For what it's worth, I did the work in getting Derek Moran's two Magnum 36s diassembled and fitted with Boca Bearing-sourced replacement bearings. As he was generous enough to buy three complete sets I immediately fitted my own engine with new bearings.
**Not an advertisement for rework.** I did this for a friend to whom I owe a couple favors.
As to typical failure mode, it was Keith Varley's engine in his 2004 Saturn. It seemed to run fine at start-up, but once in the air it pretty quickly went over-lean, eventually just giving up, Keith landing the smoking-hot model. Rob "Duck" Duckering took one look, felt the spinner, rocked the crank back and forth. "You're losing the rear bearing," and went on his way...
The spinner was very hot, as was the engine of course. But the spinner was a lot hotter than one normally sees after even a sagging-lean run. There was a bit of graunchiness (technical term) in feel of crank, both in flipping prop and (better) lightly rocking crank to and fro.
Chris Cox and I continued with our fuel-feed related theories. Wrong move, as we got it all buttoned back up, started and launched. Repeat performance of previous flight. Duck had been right all along, as shown when Keith went home for his spare 36XL, finding some nasty junk in now-trashed motor.
Interestingly enough, if we had simply held off launching the model for a minute or so I'm pretty sure bearing problem would have reared its head without putting in a flight. Would this have saved piston/cylinder set? Probably not.
While I expect few to do so, there is an old trick from my RC car days which results in bullet-proof bearings for any engine. Take two stock bearings and disassemble by removing steel retainers. The outer flange on inner race is notched using a 1/8" carbide bit in hand-held grinder. Inner flange of outer race is notched in the same way.
**Do not let this notch extend into raceway for balls.**
With light grease applied to outer race, begin putting balls into place. Slip inner race in. Add as many balls as possible.
Lining up the notches you cut, place a ball atop notches. It won't go in. Until you whack it with a hammer, ideally using a piece of hardwood as a drift pin. Outer race flexes out, inner race in, ball pops into place.
Repeat until you can maybe get in one more ball. Don't. You're done. And no more scattered retainers, as you no longer have one.
Note: Phenolic retainers have made this practice nearly obsolete, but it is still quite effective.
As to details, I simply cannot tell you exactly how deep to cut the notches, for example. This is very much a cut-and-try sort of deal.
I will tell you that while I have had a lot of success with this modification, friends have reported shattered outer races and other sorts of humorous happenings. Including building/modifying graunchy rear bearings, exactly what they are trying to avoid while drastically increasing reliability.
Dan