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Engine basics => Engine set up tips => Topic started by: frank mccune on August 02, 2020, 06:12:59 PM
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An engine that has AAC construction sounds like great design. What are your thoughts about this idea?
Tia,
Frank McCune
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An engine that has AAC construction sounds like great design. What are your thoughts about this idea?
Yes, you might get that to work.
2019 David Fitzgerald Thundergazer PA75
2018 David Fitzgerald Thundergazer PA75
2017 David Fitzgerald Thundergazer PA75
2016 David Fitzgerald Thundergazer PA75
2015 Paul Walker P-47 Plettenberg
2014 David Fitzgerald Thundergazer PA75
2013 Paul Walker ?? Plettenberg
2012 Doug Moon Bear PA 65
2011 David Fitzgerald Thundergazer PA75 Muncie, IN
2010 Bill Werwage P-47 Thunderbolt PA61 Muncie, IN
2009 Dave Fitzgerald Thunder Gazer PA 75 Muncie, IN
2008 Orestes Hernandez Yatsenko Shark Discovery Retro 60 Muncie, IN
2007 Orestes Hernandez Yatsenko Shark Discovery Retro 60 Muncie, IN
2006 Brett Buck Infinity RO-Jett 61 Muncie, IN
2005 Paul Walker For Reals OS 40 VF Muncie IN
2004 Dave Fitzgerald Star Gazer IV PA 61 Muncie IN
2003 Dave Fitzgerald Star Gazer IV PA 61 Muncie IN
2002 Paul Walker P-51 Miss America Saito 56 Muncie IN
2001 Dave Fitzgerald Star Gazer IV PA 61 Muncie, IN
2000 Ted Fancher Final Edition PA 61 Muncie IN
1999 Dave Fitzgerald Star Gazer III PA 61 Muncie IN
1998 Paul Walker Impact OS 40 VF Muncie IN
1997 Dave Fitzgerald Star Gazer I PA 61 Muncie IN
1996 Bob Baron Pattern Master Super Tigre 60 Muncie IN
1995 Ted Fancher Great Expectation OS 46 VF Pasco WA
1994 Paul Walker Impact PA 40 Lubbock TX
1993 Paul Walker Impact OS 40 VF Vincennes IN
1992 Paul Walker Impact OS 40 VF Westover AFB MA
1991 Paul Walker For Reals? OS 40 VF Vincennes IN
1990 Paul Walker Impact OS 40 VF Vincennes IN
AAC engines in bold- and these are just the winners, almost all the other competitors used them throughout this period.
Brett
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PAs are AAC. All the F2D motors are AAC. Pretty sure the Rojetts are as well.
Metalurgy is probably the best and it is lighter than ABC.
But chroming aluminum is nowhere near as easy as chroming brass, so not that common in normal production engines.
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David went straight from the 61 to the 75? He missed out on the 65?
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Thanks for the education! I had no idea that AAC construction was so prevalent. I must get out more. Lol
Be cool,
Frank McCune
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just to clear up F2A speed which runs in the 30-40,000 rpm range have gone back to Brass cylinders because they hold their shape better than aluminum and not worried about the extra weight.
for stunt and even racing ,aluminum works great
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David went straight from the 61 to the 75? He missed out on the 65?
Yes. For a long time, a .65 was not legal for FAI, so he stuck with the 61 - which didn't seem to hold him back too much. He only changed when the 75 came along.
Brett
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The Enya 60X was released in about 1975 and was AAC which was then used later in some of their smaller sizes. Apparently the 60X was the first true AAC but a couple of other earlier engines (YS-60 and Ross 61) had a chromed aluminium liner but with a ringed piston.
Personally I think the Norvel AAO is the best with their ceramic coatings and integral fins so no heat barrier between the liner and crankcase.
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Yes, you might get that to work.
2019 David Fitzgerald Thundergazer PA75
2018 David Fitzgerald Thundergazer PA75
2017 David Fitzgerald Thundergazer PA75
2016 David Fitzgerald Thundergazer PA75
2015 Paul Walker P-47 Plettenberg
2014 David Fitzgerald Thundergazer PA75
2013 Paul Walker ?? Plettenberg
2012 Doug Moon Bear PA 65
2011 David Fitzgerald Thundergazer PA75 Muncie, IN
2010 Bill Werwage P-47 Thunderbolt PA61 Muncie, IN
2009 Dave Fitzgerald Thunder Gazer PA 75 Muncie, IN
2008 Orestes Hernandez Yatsenko Shark Discovery Retro 60 Muncie, IN
2007 Orestes Hernandez Yatsenko Shark Discovery Retro 60 Muncie, IN
2006 Brett Buck Infinity RO-Jett 61 Muncie, IN
2005 Paul Walker For Reals OS 40 VF Muncie IN
2004 Dave Fitzgerald Star Gazer IV PA 61 Muncie IN
2003 Dave Fitzgerald Star Gazer IV PA 61 Muncie IN
2002 Paul Walker P-51 Miss America Saito 56 Muncie IN
2001 Dave Fitzgerald Star Gazer IV PA 61 Muncie, IN
2000 Ted Fancher Final Edition PA 61 Muncie IN
1999 Dave Fitzgerald Star Gazer III PA 61 Muncie IN
1998 Paul Walker Impact OS 40 VF Muncie IN
1997 Dave Fitzgerald Star Gazer I PA 61 Muncie IN
1996 Bob Baron Pattern Master Super Tigre 60 Muncie IN
1995 Ted Fancher Great Expectation OS 46 VF Pasco WA
1994 Paul Walker Impact PA 40 Lubbock TX
1993 Paul Walker Impact OS 40 VF Vincennes IN
1992 Paul Walker Impact OS 40 VF Westover AFB MA
1991 Paul Walker For Reals? OS 40 VF Vincennes IN
1990 Paul Walker Impact OS 40 VF Vincennes IN
AAC engines in bold- and these are just the winners, almost all the other competitors used them throughout this period.
Brett
There was also a TON of trophies won with the AERO Tiger powered ships , which are all AAC, . As well as the 100s of OS -VF conversions, OPS AAC converted engines, and a few others.
In addition there are many Combat engines that are AAC construction.
Randy
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There was also a TON of trophies won with the AERO Tiger powered ships , which are all AAC, . As well as the 100s of OS -VF conversions, OPS AAC converted engines, and a few others.
In addition there are many Combat engines that are AAC construction.
Randy
Of course. AAC and ABC engines have been around *forever* and have dominated the system for 3 decades now. Iron liners, ringed engines, baffle-piston engines, are just about museum displays.
Brett
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Steel cylinder, meehanite iron piston. The design of the future.
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Propably not a welcome opinion in here, but I haven't seen much domination of (piped) AAC engines in recent world- or European champs and other contests where I've been to. Quite opposite; in the past champs in very hot and difficult weather, like in France and Bulgaria, the piped engines seemed to be suffering more from the conditions.
And I wouldn't say that piston deflectors and -rings belong to museum, just look at Yuriy Yatsenkos decades of work with his engines, in skilled hands they are as competitive as anything else. And some Stalker's ain't bad either, just look at the track record.
About rings, it's interesting that the real engine experts, including those that more or less invented the ABC/AAC -technology, and the abovementioned Yuriy, all seem to understand that ideally the ringed setup is the way to go. Even I have proved, at least to myself, its phenomenal stability through quite extreme weather conditions.
But the post-traumatic stress is quite deep in peoples minds, from the era of crappy metallurgy and castor oil.
The ringed setup has to be made so well and carefully that it wouldn'd be profitable to make them.
With an AAC/ABC stunt engine we are talking about a very fragile harmony (maybe slightly less so with pipe), and with a ring it becomes clearly more stable and predictable.
Ring is not a time-bomb, it does not have a short life span, but it has to be made very very well. L
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Steel cylinder, meehanite iron piston. The design of the future.
Still truly beautiful
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Many AAC and ABC setups are DEAD reliable, in all conditions, Especially the PA and the massive amount of other AAC and ABC Ringless engines I , and others have made, Just look at the record, people that tell you they are not, are flat wrong ! There are also many stock fragile OS VFs that have lasted 2 to 4 times longer than most ALL ringed engines, and ran reliably, as well as other brands of ABC and AAC
The AAC and ABC last a very long time, unless treated bad. The VAST majority and I mean in the 99% range of Ringed engines do NOT last anywhere near as long as a good AAC setup. That is a fact !, matter of fact they average about 25 to 30 percent of the life of an good AAC. I have flown these setups all over the usa and Canada, in high altitude, extreme heat, Texas Washington, Florida South Georgia, Louisiana in july etc, It has alway been flip n fly.
This can be confirmed by pilots all over the USA and the World!, I have Aero Tigers past 2000 flights that are still going strong with never having been opened back up Dave Fitzgerald handed me a 61 PA after 1 of the many NATs that he used it in, and said had more than 2400 flights, Dave logs every flight in a book. Same with Bill Werwage, and many many other pilots. So people that tell you different do not know what they are talking about.
Super Tiger 60s ST 46s ST G51 , HP40s, OS FSRs and many clones, OS 40H, OS SF and a host of others ,most all ringed are good for about 500 flights before you need to rebuild them.
I have many customers that went off these engines and went to AAC lapped ones, with very good results in all areas
Check with pilots about things like this, and if you are a pilot that has to buy equipment, and do not have the machines chroming vats, mics, hones or knowledge , and friends who can help you, make a good AAC ringed setup, you will be in the same boat going to any commercially available ringed stunt engine ! They will NOT be as stable, last as long, or produce consistent reliable power .
Randy
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Propably not a welcome opinion in here, but I haven't seen much domination of (piped) AAC engines in recent world- or European champs and other contests where I've been to. Quite opposite; in the past champs in very hot and difficult weather, like in France and Bulgaria, the piped engines seemed to be suffering more from the conditions.
And I wouldn't say that piston deflectors and -rings belong to museum, just look at Yuriy Yatsenkos decades of work with his engines, in skilled hands they are as competitive as anything else. And some Stalker's ain't bad either, just look at the track record.
Your opinion is always welcome, but Lauri, you are doing something *completely different* than any consumer engine ever managed, or that can practically be achieved by the average pilot. I am sure that if I had a full precision machine shop and enough time to work it out, I am sure I could come up with a reasonably reliable ringed engine. You were previously talking about fits to 10s of microns, which is FAR FAR beyond anything that a mass-market or even semi-custom manufacturer could manage.
Even a Fox, produced in the crudest way possible on manual or mostly-manual machines, by the million, is far more reliable and predictable than even the best consumer ringed enginesm for at least stunt engines. It's not the greatest engine in the world but one thing it never, ever did, in thousands of flights I flew with it, was just change characteristics for no reason. That happened 3 times on a good weekend with an ST46. Made with precision machines to a high standard, OS cranks them out by the million - they are all the same from unit to unit, to the point they pre-set the needle for a breakin - and it actually works!
Randy is 100% correct, AAC/ABC is *the right way to go* for any sort of semi-production or production system, it's darn near bulletproof, to the point that barring some debris running through it, they essentially never fail. I wore out exactly *1* engine the entire time I have been doing this, excluding bearings failing and taking out the cylinder/piston - the supposedly "fragile" 40VF, that wore out well north of 2000 flights. Even then, it still never really went over the hill and never did anything too unexpected, just very slowly lost power. The one I wore out, on its last flight, scored a 595 in qualifying at the NATS and was #1 on the circle, even though I had to set it sagging lean on the ground just to get the lap time.
Brett
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Propably not a welcome opinion in here, but I haven't seen much domination of (piped) AAC engines in recent world- or European champs and other contests where I've been to. Quite opposite; in the past champs in very hot and difficult weather, like in France and Bulgaria, the piped engines seemed to be suffering more from the conditions.
And I wouldn't say that piston deflectors and -rings belong to museum, just look at Yuriy Yatsenkos decades of work with his engines, in skilled hands they are as competitive as anything else. And some Stalker's ain't bad either, just look at the track record.
About rings, it's interesting that the real engine experts, including those that more or less invented the ABC/AAC -technology, and the abovementioned Yuriy, all seem to understand that ideally the ringed setup is the way to go. Even I have proved, at least to myself, its phenomenal stability through quite extreme weather conditions.
But the post-traumatic stress is quite deep in peoples minds, from the era of crappy metallurgy and castor oil.
The ringed setup has to be made so well and carefully that it wouldn'd be profitable to make them.
With an AAC/ABC stunt engine we are talking about a very fragile harmony (maybe slightly less so with pipe), and with a ring it becomes clearly more stable and predictable.
Ring is not a time-bomb, it does not have a short life span, but it has to be made very very well. L
You must never have been introduced to a PA-65...
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You must never have been introduced to a PA-65...
Oh I have been, even used one (51 if I remember right) briefly. They're nice but not what I'm looking for. L
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ite opposite. We could as well make it AAC.
The problem we see with ringless is the eternal uncertainty of piston clearance in different temperatures. It's not really about sealing, but about stabilizing the thermal flow.
Which appears to have absolutely *no* practical effect, given the remarkable run stability of even mass-production engines cranked out by the hundreds of thousands. My (and most other people's) experience with production or even aftermarket ringed engines was that no two rings ever produced the same results, and that it appeared to skate, hydroplane, go out of round, stick in the groove, loosen up in the groove, spin around, etc, *all of which appeared to have drastic effects on the way it runs*, like a random-number generator.
Fine for 3 weeks straight, you would think "hey, I finally got it working", then the next flight, no power, or half a flight dead lean or dead rich, or it starts misfiring, quitting outright. And then you are back to square one, get out the brake cylinder hone or dig into your shoebox full of spare parts, or start screwing around with propellors to get it to break a little more, or a little sooner, put on a different head, or something like that, in an endless spiral.
I have no doubt that if you had a machine shop and could control every aspect of it, some of that might be solved, but you are talking about solving theoretical problems that seem to have nearly no effect in practice.
When it comes down to something like that VS entirely custom machine shop specials that only a few people in the world could possibly produce with tens of thousands of dollars worth of equipment, it's not a hard decision.
Brett
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..and not to mention the countless hours of running-in?
That was then, I haven't encountered any of the stability issues you mentioned. Running-in takes about 20 minutes, during which about 99,5% of wear happens of its whole lifespan. Thousands of flights, no measurable wear or nasty surprises.
You must understand that Super Tigre was not a good example of a quality product.
I have never said that this is a good business opportunity, but I have nice machines that I can use for making many things, maybe even something lucrative. This us just a side product. And a bloody interesting one. L
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As I stated earlier, IF you are buying stunt engines, Then lapped AAC is the way to go, Lauri is an excellent machinist and has a huge base of help, if he needs it, But you cannot compare his engine to ones that you can buy, and Lauri is not going to sell you one, If a manufacture made what lauri is trying to compare engines to, they would want maybe 1000 a piece for them, It is a moot point anyway, It is not going to happen, '
The commercial available ABC AAC AAN ABN are excellent, I ran 1 PA in a Vectra for 9 years, 9 Nationals many team Trials and flew the plane all over the USA, massive range of condition, perfectly stable, Never a problem, and flew in contest many times with winds that were over 20 to 30 MPH. 3 of these were at Nationals.
If you have a ring in your engine, and is commercial built, it IS an inferior product.
The best way to make a ringed engine is to make it a double ring, with thinner rings, they conform to the distortion of a hot running engine better than a single thick ring, pin each ring 180 degrees from each other, and as Lauri has done make sure you use an aluminum piston and aluminum sleeve, Make sure you make it with a slight taper in the sleeve The AAC ring is the most stable you can make, The thermal expansion is the closest, Most of the problems with rings in St OS K&B FOX etc, were from steel sleeves, The expansion rates were much more different, even 2 identical ST 60 , 1 with steel sleeve 1 with chromed steel sleeve, the steel sleeve can run a tighter gap to start than the chromed one, even with extreme care taken on ringed engines, i have NEVER seen one go much past 500 flight without wear, degrading the performance, and I have rebuild thousands of these type stunt engines. NEVER have I seen a ringed engine go over 2000 flights with NO wear on the ring.
Lauri's engine is NOT , in any way, a typical stunt engine. It is a extreme example of 1 off custom built high tolerance engines. So if you are not able to do what he does, and are looking for available engines, there is ZERO reasons to compare the ones against his, the argument is pointless.
I have many custom made engines here, that have 100s of hours into them making parts and assemblies testing running, I have 8 ounce 64s, 7 ounce 40s, light extremely stable 55s, BUT these are NOT ones I could sell to people as a line of stunt engines at any reasonable price.
To close I will mention that there are STILL people flying engines from the 1980s and 90s that are AAC and ABC with great results, and they are still powerful stable and working perfectly, These include OS VF FSR , Clones, OPS rear Ex AAC, HP 40s, Royal 45s, PA 40s and 51s, OS 35 S engines, Thunder Tiger built Magnum AAC engines
Randy
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Thank you, Randy.
Actually, I prefer a Dykes ring. L
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Thank you, Randy.
Actually, I prefer a Dykes ring. L
Yes so did STan Powell, and a couple of other of my friends. I prefer to have the added compression of the setup I described
Regards
Randy
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>:D >:D >:DAnd then there was electric >:D >:D >:D ;D ;D ;D
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It seems Top Fliers missed to look at some AAC engines available in the 80s and 90s, like the Enya 45X AAC the Enya 45CXL AAC with rear exhaust. At least I never heard of any one using one of these AAC engines back then.
Martin
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It seems Top Fliers missed to look at some AAC engines available in the 80s and 90s, like the Enya 45X AAC the Enya 45CXL AAC with rear exhaust. At least I never heard of any one using one of these AAC engines back then.
Nobody missed out on them - a few people in the 80's tried them, they were not nearly as good as the more established 40/46VF or ABC. I think the side-exhaust version was one of the "schneurle war" engines.
Brett
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Who tried any of these 2 Enya AAC engines to claim they were not nearly as good as OS 40/46VF, which you know were not ABC but ABN.
Brain Eather told he thought the Enya CXL was much better then OS VF. Paul Walker told me he didnīt know about these engines back then.
This is an Enya 45CXL P/L, look how thick it is. Does it look like not nearly as good as an OS ABN? I think it is quite the contrary. I measured 145o total exhaust time.
Martin
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Thi is the Enya 45CXL AAC
Weighs 11.2oz
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Having read all of this it's strange to think that a production line and readily available ringed engine like a Saito would ever be successful.
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Having read all of this it's strange to think that a production line and readily available ringed engine like a Saito would ever be successful.
Lots of stuff can be made to work and there have been plenty of other ringed engines far more successful than the Saito many decades before.
Brett
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Lots of stuff can be made to work and there have been plenty of other ringed engines far more successful than the Saito many decades before.
Brett
I think the ST.G-.51 is a good example of that. I have had a lot of good service from the examples I have been using and I call it my "main weapon." The engine is very reliable, is of a decent weight but robust construction, very reasonably priced, and lends itself to simple but effective modifications if desired. I have had great service out of them both stock and "reworked" but that doesn't mean that they were extensively modified or retimed. I have a few Tom Lay handled engines, and like the rest of the work he did, he just made sure the cylinders were round, had a good fitting hardened ring for longevity, optimized other fits, and if I remember correctly, replaced the roll pin that located the piston ring with a solid pin . Of the three or four ST.51's that I have had in operation, I have yet to have had the need to replace the ring in any of them. I may not have won the NATS using these, but I may never win the NATS using any other power plant either! With the way I have had to pursue the hobby kind of hit and miss and on short notice during my working career, I found them very satisfactory to use and operate and I did pretty well with them on a local and regional level in Expert competition. A ringed engine is just another good option for a power plant. I will say this,( and I think Brett has tried to be gentle in his appraisal of things,) there are some people that can screw up a two car funeral!! You can hand them a great operating system and that has been proven and test flown, and they will still find a way to mess things up!
Type at you later,
Dan McEntee
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Hello We were told to get an ABC Fora Junior Diesel for a slow Goodyear model as the AAC version cools down too much due to the uncowled profile set up and ABC holds the heat in for better restarts. Could this would not apply to profile models with AAC engines if hotter running glow types.
Regards Gerald
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Parra engines make a 2.5cc engine in both glow and diesel and in three piston/ liner types.
Steel/steel/ chrome, aluminium/chrome/aluminium and aluminium/ chrome/ brass and warn that the steel option should not be used with a large prop load because the wrist pin eggs out.
Probably due to piston inertia at both dead centres resisting crank rotation.