RE: EVO10GX MODS
Idle rpms were checked today with numbers ranging from 1800-2000. Got a couple of blips in the 1700 range and a couple in the 2100 range.
Posted on: 5/23/2013 6:00 PM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11520758

RE: EVO10GX MODS
Evgeny.. I would never suggest that you are not knowledgeable. I understand that you have space constraints where you fly and when I compare my first landings with my 10GX powered plane with a 11x6 prop screw to those now with the 14x4 there is great contrast and the plane lands much slower. Above I provided an edit to my previous post saying that I don't know if fuel collects in the idle bar and that if it in fact serves a positive purpose during spool up as a static accelerator pump. If so, my suggestion to close off the spray bar would be poor advice. I simply do not know. edit... sport flyers are generally more interested in flying than refining an engine. They wish for general reliability out of the box where their focus can be on the flying.
Posted on: 5/23/2013 8:08 AM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11520201

RE: EVO10GX MODS
I've noted the positive statements about the engine but have also noted that some have concluded the engine has problems simply based on the rhetoric about needs for modifications. Once again, I applaud the efforts to refine the design towards perfection, but suggest that most sport/scale users do not require perfection. I've previously outlined that my engine has suffered no dying problems, in fact quite the contrary... it is more resilient to keep running when compared to glow engines. It has been months now since I tached the idle RPM's and I don't recall what the number was, but can say without hesitation that the idle is sufficiently slow that the model does not roll at idle and slows very well during landings and does not die when landing. Again, my success may be due to the APC 14x4 prop. As to a simpler fix for the possible fuel dumping, simply plug the end of the spray bar with a brass rod and solder or insert a dob of JB weld. There could be many variables in place such as comparing a fast against a slower throttle servo. Maybe my throttle servo is simply too slow to cause the effect that a faster servo might? edit note: I'm not an expert on carburation. When I suggested an easier fix would be to close the end of the spray bar if fuel dumping when closing the throttle was an issue, I might have overlooked that the idle bar might in fact serve a secondary positive effect beyond the idle metering. It is possible that fuel does collect in it and then serves as an acceleration reserve when the throttle is opened quickly, thus helping to avoid spool up stumble and a required too rich of idle setting. If that is the case, Evgeny's design does not provide for such. I simply say... I don't know if the idle bar is intentionally designed to provide the spool up dump or even if fuel collects in the idle bar. I'm back tracking my words however and wouldn't close the spray bar end off without an expert suggesting it is ok. There are several engine experts among modelers and perhaps some will weigh in on the question.
Posted on: 5/23/2013 7:57 AM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11520169

RE: EVO10GX MODS
The engine runs well for me. I don't even know that the carb design in fact fuel dumps as suggested and am somewhat doubtful that fuel collects in the idle bar. Even if it does and is a problem, a fix is simpler than making new carb parts.
Posted on: 5/23/2013 6:56 AM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11520140

RE: New Evolution Engines!! 15GX, 20GX, 33GX
I've started efforts to re-power an aerobatic model from Saito 1.25 to Evo 33. The plane has hardwood rail engine mounts hence why the Evo 33 was chosen and they have perfect spacing of 1- 15/16" for the engine so as expected the engine dropped in. The Saito 1.25 doesn't have that kind of width but the beams were originally set up for a YS - 120. The muffler however has some clearance issues with both the muffler wrap around header and the muffler body. The body will not be much issue, just cut away a little of the lower fire wall but the header clearance will need a cowl blister. The plane was set up for three degrees of thrust which has the beam mounts shifted to port exasperating the clearance problem. A cowl blister isn't a terrible issue as it will give opportunity to close up the hole used by the Saito muffler header and the cowl was in need of a paint job anyway. I'm thinking one of larger plastic easter egg halves will make a good mold to lay the glass into.
Posted on: 5/23/2013 6:27 AM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11520111

RE: EVO10GX MODS
My pudding has not had any dieing problems and idles fine, but as mentioned previous, that may be due to running a 14" prop.
Posted on: 5/22/2013 6:59 PM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11519790

RE: EVO10GX MODS
Or.... just plugging the end of the spray bar.
Posted on: 5/22/2013 6:47 PM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11519779

RE: Help in ID'ing plane
A YS engine would however narrow the scope of interest as YS invokes love em or hate em.
Posted on: 5/18/2013 6:56 AM by Author "AA5BY" in the forum "Sport Flying"
http://www.rcuniverse.com/forum/fb.asp?m=11515082

RE: Foam Cutting Power Supply - Train Transformer
To add some idea of what will work, the train transformer used here is a Lionel, 50 watt, 8-15 volt and will run a 44 inch bow with nichrome wire at about a 3/4 power setting.
Posted on: 5/18/2013 5:09 AM by Author "AA5BY" in the forum "Tips & Techniques"
http://www.rcuniverse.com/forum/fb.asp?m=11515028

RE: New Evolution Engines!! 15GX, 20GX, 33GX
Speaking of waiting... I had a 15&33 GX coming.... This notice alerts you that the shipment listed below has been delivered. Shipment 1 Tracking Number: xxxxxxxxxxxxxxxxxx Shipper: HORIZON HOBBY INC. Delivery Time:[color=#0033FF]7:54 PM[/color] Delivery Location: RESIDENTIAL
Posted on: 5/17/2013 8:20 PM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11514842

RE: New Evolution 10cc gas engine
[quote]ORIGINAL: brunofporto No, He is not trying, in this case, to achieve maximum power.  He already consider this engine very powerfull out of the box. He is trying to achieve a reliable idle behavior of the engine. Also a reliable behavior of the engine at any throttle position by modifying the carburator to a proven design solution. [/quote] Performance is a word that sometimes gets restricted to power but it generally includes all aspects of running such as power, economy, smoothness, acceleration, power to weight ratio, longevity, reliability and probably more. Sorry, I've a different take. Perhaps and probably not intentionally, to me he has painted a picture critical of the engine. From my perch, he initially chronicled a melt down of the engine and accepted none of the possible responsibility and even said that time would see all 10GX's melt down. He took opportunity to be critical of the centering of the needle assembly in the carb when from my view it was a red herring. If the needle had been offset in the assembly, yes... it could be an issue... but it wasn't the needle that he was detailing, it was the assembly into the carb and a couple of thousands on it should have no affect that I know of. He now offhand discounts the value of the 15 & 20GX. He has confronted Pete as not interested in doing the right thing. He has not acknowledged that there are some who are happy with the engine, even suggesting that I'm a critic of the engine because I outline more vibration than glow when every gas engine owner likely knows and expects that gas engines have more vibration than glow. All I'm trying to say is, I'm a sport/scale pilot/modeler and bought an engine and out of the box it is performing beyond my expectations. It is not for Evgeny and he has every right to say so and I simply want to be a counter voice and have every right to be so.
Posted on: 5/16/2013 5:11 PM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11513651

RE: New Evolution Engines!! 15GX, 20GX, 33GX
I took off this afternoon to be here for UPS to sign for the shipment, but UPS updated they had weather problems and delivery was delayed until tomorrow. I'm expecting both the 15 and 33.
Posted on: 5/16/2013 3:25 PM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11513558

RE: New Evolution 10cc gas engine
[quote]ORIGINAL: brunofporto I think that one of his hobbies is work on engines to make them qith better performance. He is not frustraded by the engine, it is the opposite! [b]He is quite happy that the engine have a lot of potential[/b]. :D I find it very interesting.  [/quote] I stand behind my observation. It seems to me that Evgeny is frustrated with the GX because he wishes for a high performance engine and [b]sees the possibility for such in the GX series with a bit more effort.[/b] Very similar don't you think? As to frustration... "Pete why I love your engines - they have potential. [b]But you have no desire to make perfect their products[/b]. And you cann't put on the blades OS Engine. But why not allow the production to love what they do ... " Those seem like frustrating words to me but confess that what seems to me is not always correct.
Posted on: 5/16/2013 3:06 PM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11513543

RE: New Evolution 10cc gas engine
Evgeny... I've meant no offense and have taken none. We are both Aero modelers and if I'm wrong that you are motivated by maximum performance, my apology. Surely from your post you can appreciate my reasons for the conclusion. You describe a tuned pipe, and other details associated with maximizing the performance of an engine. Sport/scale modelers generally don't go to the efforts that you have outlined. They generally pick and engine that out of the box will fit the airframe for power and weight and then simply fly it. As to the idle of the 10GX... mine idles well but that might be because of the choice of prop as mine is swinging a 14x4 so it likely helps produce a lower idle. As well, dead sticks have not been a problem for me. The engine starts easily by hand and runs well. Yes, I've outlined that mine has more vibration than a similar glow engine. I don't however believe the vibration is excessive but it does require specific action regarding the muffler... to use a sealant of high enough temperature rating between the muffler parts and the muffler and engine. As to the source of the vibration, I'm not qualified to speak. Others have outlined that it is typical to gas to have greater vibration due to more rapid combustion. I don't know if that is true or not. I'll add my voice to having enjoyed your post and observations and also say that I generally understand what your saying.
Posted on: 5/16/2013 2:45 PM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11513522

RE: New Evolution 10cc gas engine
It might be that apples and bananas are being compared. What I mean is that our Russian friend seems to be thinking high performance vs sport, whereas the Evolution GX series seems to be sport/scale designed rather than high performance. A few years ago, I bought a YS and soon decided it was a performance engine and a bit too problematic for sport use. I concluded not to use it and have never bought and have no plans to ever buy another as I'm a sport/scale pilot and don't want to deal with the issues of a high performance engine. It seems to me that Evgeny is frustrated with the GX because he wishes for a high performance engine and sees the possibility for such in the GX series with a bit more effort. Personally, I don't want the extra cost of a high performance engine or the frustrations that sometimes come with them.
Posted on: 5/16/2013 11:54 AM by Author "AA5BY" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11513382

RE: evolution 10gx issues
You are one up on me... I've three Zenoah G-20s but I've six Zenoah's in all, with two 26's and a 23.
Posted on: 5/15/2013 7:29 AM by Author "AA5BY" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=11512175

RE: evolution 10gx issues
Bet you can't stay away from the apple pie during fall festival at Hemet as they are really good... if not the best apple pie I've ever had. As to the 10GX. I've enjoyed mine but confess benefiting from those who had troubles with the muffler leaking. That awareness motivated the use of copper sealant before ever running the engine. I am experiencing more vibration than with glow. On the plus side, a lot less fuel cost. Far less clean up. No field box needed as it starts easy by hand and requires no glow igniter. Can use a larger prop for less noise as power band is wider. On the negative side is more vibration and the necessity of taking precautions.
Posted on: 5/15/2013 7:11 AM by Author "AA5BY" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=11512158

RE: evolution 10gx issues
All tanks have a vent line... in your case the vent line is also the muffler pressure line.
Posted on: 5/15/2013 2:10 AM by Author "AA5BY" in the forum "Questions and Answers"
http://www.rcuniverse.com/forum/fb.asp?m=11511996

RE: Having engine, wing and horiz. stab on a common centerline as opposed to having it otherwise.
Planes like the Kaos .40 are of the size that the drag couple is probably not an issue to be of much concern. When entering the world of giant... drag couple becomes an issue. My initiation to it happened with the BUSA Phaeton .90. The greater drag of the upper wing and longer lever arm compared to the bottom wing had the plane climbing badly, which had to be countered by some negative wing incidence. On the Spacewalker, the drag problem was opposite and pitching the plane down.
Posted on: 9/9/2012 11:40 AM by Author "AA5BY" in the forum "Aerodynamics"
http://www.rcuniverse.com/forum/fb.asp?m=11222849

RE: Scratch Building 1/4-Scale Pitts Model-12
Much depends upon the field condition and I'm coming from a pretty rough field where few ARF gear supports are adequate and the additional weight of gear reinforcing is needed and in fact welcomed to avoid headaches of ripped out gear on landings that weren't that hard. Sounds like you have thought the issue well and that was my primary concern.
Posted on: 9/9/2012 8:20 AM by Author "AA5BY" in the forum "Scratch Building, Aircraft Design, 3D/CAD"
http://www.rcuniverse.com/forum/fb.asp?m=11222718

RE: Scratch Building 1/4-Scale Pitts Model-12
The last picture offers a view of a concern that I've felt since the beginning of the design, that being the gear strut mounting. I might be (hope I am) wrong in my perspective that it is a good thing when gear stress cancels in a common mount and without a common mount there is no canceling so the supporting structure needs to be quite strong. I think the way the struts are mounted is fine but I'd like to have seen a box structure between the two with all thread screws traversing both mounts. As is... gear stress might/will lever the mounts away from the former and failure with a difficult surgery to repair. With the covering not yet on... not too late to think about that. One plan might be to simply add two all thread rods (one up and one down) with both interior and exterior washers/nuts traversing between the two mounts and gear struts. Doing so, there would be no need to change any of the existing mounting screws and the result would offer stress canceling. The reason for the interior washers/nuts is that the upper rod would see compression loads whereas the lower would experience extension loads.
Posted on: 9/9/2012 5:51 AM by Author "AA5BY" in the forum "Scratch Building, Aircraft Design, 3D/CAD"
http://www.rcuniverse.com/forum/fb.asp?m=11222562

RE: Tip-stall prone Cub
Yeah... no twisting a foam cored wing. I could be wrong about it being clipped... just looked that way in pic to me.
Posted on: 9/8/2012 1:50 PM by Author "AA5BY" in the forum "Crash & Rebuild"
http://www.rcuniverse.com/forum/fb.asp?m=11221988

RE: Having engine, wing and horiz. stab on a common centerline as opposed to having it otherwise.
Hi Karol, I applaud your project. I did a similar last winter and went through some of the thought processes you narrate. My thinking was that drag forces should be balanced on the thrust line to avoid drag induced pitch. The three biggies are stabs, wing and undercarriage. In my case, I laid the horizontal sheet stab as one would do on an inverted stick fuselage. I guessed that the stabs would have a fair amount more drag than the undercarriage so that meant dropping the wing (by far the greatest drag factor) slightly below the engine thrust in hopes of having better drag balance. IIRC, the wing is 5/8" below thrust line and the horizontal stab is 1.75" above. I don't know that there are any magic numbers but for good flight manners... some thought might help. An example of poor would be a Spacewalker I built. The engine is high, and it has a large low wing and center stab. That means that the big three drag factors are all well below the engine thrust line and considerable lever arm on the high drag of the wing. It was no surprise that the plane required a lot of up trim even though engine, stab and wing were all carefully set zero. Ultimately, I had to adjust the wing incidence positive to get the power on/off trims into alignment. I considered my project a great success as the plane required only two clicks of down trim and no roll trim on maiden. If the wing had been left on thrust center line where first drawn... no doubt more down trim would have been needed. Offsetting it 5/8" down from thrust line countered most of the stab drag. Finally, the project was a real thrill beyond any previous build. Part of that was because the plane was designed around what tickled my gizzard the most, it was my creation. And.... it was my responsibility to ensure it would be a success and that forced a lot of thought and effort beyond what one normally puts into a kit or built to another's plans. Wishing you a lot of fun and enjoyment in your effort. I'd concluded even if it didn't fly great and perhaps turned out to be the field ugly duckling the experience was worthwhile but when it looked good and flew great, the satisfaction of accomplishment was overwhelming. I love to fly the plane. PS: I'd drop your wings to about 1/4-3/8" below thrust line if the stab is 3/4 or so above.
Posted on: 9/8/2012 11:52 AM by Author "AA5BY" in the forum "Aerodynamics"
http://www.rcuniverse.com/forum/fb.asp?m=11221899

RE: Tip-stall prone Cub
Your Cub is a clipped wing version and more aerobatic than a standard cub. You are right however in that many Cubs will tip stall and some easily. I've both a Goldberg Anniversary Cub and a World Models. The builder of the Goldberg added washout to the wing and it is very forgiving, while the World Models is not so much. After a tip stall and rebuild of the World Models, effort was made to tame it a bit with a few changes. Ailerons were given some differential and up trim at lower throttle to simulate washout. Some rudder mix was added. The up trim works fairly well with barn door ailerons and would work on your model or you could try to introduce some washout by twisting the wings and shrinking the wrinkles.
Posted on: 9/8/2012 8:06 AM by Author "AA5BY" in the forum "Crash & Rebuild"
http://www.rcuniverse.com/forum/fb.asp?m=11221723

RE: Gas engines for smaller planes
I think there is a Revolver thread in the ARF forum that might provide more attention to your question. IIRC, there has been some discussion there about 20cc gas engines fitted to .60 size Revolvers. Best of luck.
Posted on: 9/4/2012 9:24 AM by Author "AA5BY" in the forum "Sport Flying"
http://www.rcuniverse.com/forum/fb.asp?m=11216986

RE: inverted flight question.
Adding slightly to what da Rock says about the mains position... in my experience, the more lift the wing has, the more critical the gear position. I designed and built a plane last winter having 96 inches of span on a 35cc size plane. It porpoised on landings and lifted off before the tail would come up. Adjusting the gear position aft solved both issues.
Posted on: 8/27/2012 4:22 AM by Author "AA5BY" in the forum "Aerodynamics"
http://www.rcuniverse.com/forum/fb.asp?m=11207330

RE: trim question
Check the throw of the elevators. For whatever the reason, when I mix two elevator servos, the slave always has more throw and requires a 94-96% setting compared to the primary. I find the number is critical... one percent up or down will manifest the tracking problems in a loop.
Posted on: 8/27/2012 3:43 AM by Author "AA5BY" in the forum "Aerodynamics"
http://www.rcuniverse.com/forum/fb.asp?m=11207311

RE: JR 11X Rudder Gimbal
I had the pin come out on a JR 7202 elevator gimbal. Fortunately it was while flipping the elevator during a range check. Like you, CA locked it in place with no more problems.
Posted on: 8/16/2012 9:24 AM by Author "AA5BY" in the forum "JR Radio & Spektrum Radios"
http://www.rcuniverse.com/forum/fb.asp?m=11195785

RE: inverted flight question.
You might verify that both ailerons are trimmed properly, that both are not down a little or up a little.
Posted on: 8/13/2012 7:33 AM by Author "AA5BY" in the forum "Aerodynamics"
http://www.rcuniverse.com/forum/fb.asp?m=11191513

RE: Ugly Stck goes in and don't know why??
This might be one of those tough ones to nail down. FM normally goes wild with a contending signal which leaves the thinking that signal was lost for an unknown cause. The cause could be a lot of things such a range problem or receiver or transmitter failure. An antenna not extended, low transmitter battery, loose antenna, receive crystal failure, cold solder joint in receiver, broken receive antenna, receive antenna degraded by close proximity to metal control cable or even a bad switch harness. The position of the antenna relative to the plane plays a part when range is degraded. Unless I found the cause, I'd not put the receiver in a valued airplane. It could be crystal, or a cold solder joint and if so, it might cost another airplane. Not long ago, a guy at the field was losing an occasional plane. Turned out to be a sometimes range problem and transmitter issue. He sent the transmitter in for repair but the problem persisted with another crash so he decommissioned the transmitter.
Posted on: 8/13/2012 7:13 AM by Author "AA5BY" in the forum "Crash & Rebuild"
http://www.rcuniverse.com/forum/fb.asp?m=11191493