RE: Sundowner 50 Arf
Get a Jett60, a Tettra tank, and never look back. Mid 130's to low 140's with the right prop. Good luck. C
Posted on: 3/1/2011 1:56 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10372556

RE: Sundowner 50 Arf
I have a Jett60 in mine fitted with the cigar shaped muffler. I used a rubber exhaust deflector and a short length of AL tubing. Zip tie/Yamabond the snot out of it because any fuel/exhaust leaks are going to quickly destroy the interior of your fuse. Right over the landing gear is where all this stuff sits. This little guy looks pretty cool with a zoomie stack coming out the side of the fuse. Good luck. C
Posted on: 2/19/2011 9:43 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10347919

RE: Some things to go a little faster?
Try raising your exhaust port slightly. This will raise the RPM range of the engine. A degree wheel is the best way, but in layman terms you could likely raise it around .02-.03 and be safe. It'll kill some low end but who cares, your just trying to go fast right? Balance your prop to the engine. (Huh?) Rarely are these engines actually bob weighted and spun balanced. The engineers that design them allow the software to speculate the weight of the crankshaft counterweight. If your engine is "buzzy" and WOT try taking a new prop and sanding the snot out of one blade. Time that blade's heavy side to point away from your glow plug with the engine at Top dead center. Crank it on tight and fire it up and see if you get an RPM increase and a smoother running engine. If you don't, experiment. Rotate the prop 180* and try it again. This does work. I promise. It's kinda along the lines of an externally balanced 400cid chevy small block engine. Balance your spinner. None of this is going to make earth shattering gains, but when combined it can make a significant difference. Props for these little buggers are super cheap so if you ruin one it's only a couple bucks. Play with glow plugs. The heat ranges act just like retarding/advancing ignition timing as much as they do firing the mix inside. Head shims. Raising/lowering compression affects how/where the engine makes power. General rules: If you lower compression you may be able to get away with more nitro content (assuming the air density hasn't gone up) If you increase nitro, move to a different plug to retard the ignition timing. (if I recall it right, you'll use a colder plug) Retarding the timing is critical with more nitro. Gotta do it. If you increase compression you generally have to lower the nitro content (unless the air density is crap, then you'll be fine) Hotter plug to advance the timing. An old trick is to leave the driver on the engine and run it up to WOT. Then pull the driver. If it drops RPM then you may want to switch to a plug that runs hotter. This acts to advance the timing a bit. Running heavy, heavy dosages of nitro will require a bit more engine work. The volume of fuel delivered to the carb must be increased significantly. Bladder tanks and/or perry pumps really help. enlarging the orifices in the carb will need to be done and the idle slot on the barrel will likely need some fiddling. (especially on a Moki 210 engine!) Things like port timing and fiddling with transfer ports can also net some gains but you have to be careful. You are only robbing pete to pay paul. Hope this helped. C
Posted on: 11/11/2010 10:48 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10128720

RE:
The 12x10 APC screams! I flew the snot out of it on Sunday and all was good. Yesterday my MAC pipe arrived along with a pair of 12x12 APC props. I'm optimistic. I think this'll wake things up a bit. If I'm down on RPM my intentions are to first shim the head and spike the fuel with a bit more nitro. (I have gallons of the stuff along with a hydrometer for "cooking" my own fuel) If that "kinda" works I'm going to raise the exhaust port a smidge. This will raise the usable RPM range of the engine. It'll surely kill some of the "grunt" down low but I don't care. This is a speed plane. Just has to idle reasonably well and transition to WOT for take off. I'll get some radar gun #'s once she's all done.
Posted on: 11/11/2010 10:35 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10128692

RE: Ok, so it's not RC, but it is extreme speed, and it is a prop plane
that's a alot of work for 10 seconds. . . Pretty cool.
Posted on: 11/9/2010 3:01 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10124915

Sundowner expiration: 11.07.10
My Sundowner met it's demise yesterday. The new Moki 210 (minus the blower I'm working on) ran really well and put on one hell of a show for everyone. Unfortunately I fuggered my final and she died for good. Since H9 no longer produces this plane I need another candidate for my "Blower Moki" project. Anyone know of a good speed plane that is the appropriate size for this displacement engine? Something semi scale looking (a 80" Kelly F-1 or GR7 would be excellent!) Thanks. C
Posted on: 11/8/2010 11:47 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10122611

RE: The Moki project. . .
Hard part's over! [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0013.jpg[/IMG] now onto the cool stuff again.
Posted on: 11/6/2010 4:43 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10119079

RE: The Moki project. . .
1st op on the back blower case cover is done. Just a little fluff n buff to nick the burrs off. Woo Hoo. It'll be a great "hood ornament" for my desk if nothing else. [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0008-1.jpg[/IMG] [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0009.jpg[/IMG] [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0010.jpg[/IMG]
Posted on: 11/6/2010 2:55 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10118945

RE:
I flew the other day with a 12x10 APC. Seemed to work well. I'm at 3500ft elevation so this may be why I'm getting away with the added pitch. I've ordered a MAC header/pipe set up and a couple 12x12 APC props. Maybe that will wake this thing up! I'll post results. A buddy is a cop and enjoys making "creative use" of his radar gun. More to follow. . . C
Posted on: 11/6/2010 2:10 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10118879

RE: The Moki project. . .
Afraid there's a bit more to this than just building boost. As I've come to learn "huffing" a front rotary valve 2C engine isn't as easy as it would seem. The issue comes with keeping the charge in the cylinder. The exhaust port is the first thing that opens as the piston is on its way down after firing. This compresses the mixture in the crankcase. After the exhaust piddles out the spent stuff the transfer ports begin to open and the new intake charge gets squirted up into the combustion chamber. In a boosted condition it's very likely the bulk of the charge will run right out the exhaust port. I have a couple options. One (most complicated) is to design a new head/liner with a poppet valve that's driven off a camshaft for the exhaust. The second (more realistic) is some creative use with a tuned pipe. The pipe works by taking the sound energy generated and reflecting it back towards the exhaust port to literally stuff the piddling intake charge back in the cylinder. Done correctly it's quite powerful. Tuned exhausts on 125cc motorcross engines are capable of making the combustion chamber displace up around 180cc's of intake charge volume. It makes the powerband quite narrow though as the length of the pipe determines the RPM range/broadness. This is why the "revy" 125's are often picked on as being "peddled" around the track by the gear shift lever. (to keep the thing in the optimal RPM range for max power) What I'm learning is the trick is to get that charge shot up there with enough velocity to adequately fill the cylinder while avoiding an overly "quick" charge that'll tend to run out the exhaust. If I can get the intake charge "just fast enough" then hopefully it'll fill the cylinder and loiter around while the piston changes direction and closes off the exhaust port. This leads to another challenge. The actual displacement of the engine isn't exactly correct. (Bore x bore)x stroke x .7854 is the old school displacement formula. Unfortunately it's a bit skewered for a piston port engine. The ports are open for the bulk of the rotation cycle. Actual displacement (usable) is significantly less as anything that really matters takes place from TDC (top dead center) on the piston to when the exhaust port starts to open. The trick with high nitro content is to get enough exhaust timing. This means raising the port- sometimes considerably. Doing so reduces the effective "pressure cycle" in crankshaft degrees as the pressure in the cylinder drops off pretty quick once the port opens. Raising the port elevates the effective RPM powerband of the engine. It has to run faster to make the same power as the shorter port did. Not a bad thing so long as components inside (crank, rod, piston) are able to tolerate it. I know my stock Moki 210 ran a 16x16 APC at 7400 rpm on 15%. Through extensive tinkering I was able to bump that up to 7900 rpm with 58% nitro. (I had to buy a hydrometer and learn how to blend my own fuel) What kicks my butt is my buddy down in AZ was able to run a 16x14 APC at over 9600 on the ground with 60%. I figured I should have been in the low to mid 8's with the 16 pitch. Makes me think I did something wrong but I can't find out what it is. With smaller props I got as high as 10,200 rpm (14.4x13 APC) My performance goal is to be able to spin that 16x16 at 10,000. That should really wake this engine up. If I get it then I'll look at a custom prop with more pitch. 200mph is the speed target for this bugger. A bold undertaking. I doubt I'll get it without having to really tear into the airframe but who knows? Stranger things have happened. Ok, back to work. This morning's agenda is to finish the rotors. Gear sets and all. More to follow as time allows. C
Posted on: 11/6/2010 9:38 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10118487

RE: The Moki project. . .
Oky doky, 1st op on the rotor halves is finished. Both are within a couple tenths for taper and OD. Not too shabby for a dumb farm kid. Tomorrow or next week I'll start on the 2nd operation. I've got a rifle to get started on for a client so it may have to wait a bit. Nite gents. C
Posted on: 11/5/2010 8:54 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10117839

RE: The Moki project. . .
The rotor taper was bugging the hell out of me so I decided to remake the rotors. Mucho betta!! [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0006-1.jpg[/IMG]
Posted on: 11/5/2010 7:54 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10117726

The Moki project. . .
This whole idea started with the USRA Giant Scale pylon guys opening up a class for the 80" H9 Sundowner. I put a plane together just in time for the class to be eliminated (since H9 stopped making it) So, a big plane, a big engine, and now what? We go faster for the hell of it (hopefully) I've made friends with one smert fella down in AZ that owns a machine shop and took to seeing what it takes to wring out a Moki 210. He's had quite a bit of success. A 16x14 APC at 9600rpm on 60%nitro isn't too shabby! Tore the wings right off the plane one afternoon. I've essentially duplicated his engine. (he was kind enough to share the notes with me) Although I'm at roughly half the elevation I've never been able to get the RPM he was/is so I've taken another tract. I too own a machine shop. . . The positive displacement blower project begins. . . I spent a few hours on the phone with engineers from Whipple, Eaton, B/M, and Blower Drive Service. I've gotten a good understanding of what needs to happen now. I've got my bearings, gears, drive belts, and a few CAD doodles. I've also aquired materials. Here's the basic rotor geometry: Rather than invest a huge effort into a helical rotor setup that is much more complicated to make I'm first going to keep this simple by machining a straight two lug rotor setup. Here's a few pics as I'm running the rotor program right now as we speak CAD doodles [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0007.jpg[/IMG] [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0008.jpg[/IMG] [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0006.jpg[/IMG] chunk of 7075 T6 certified aerospace forged billet aluminum. Some tool paths. Doesn't look like much yet as I have to get the bulk of this out of the way first. It'll start to make sense here soon enough. [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0061.jpg[/IMG] [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0062.jpg[/IMG] [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0063.jpg[/IMG] [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0064.jpg[/IMG] More to follow. Chad
Posted on: 11/5/2010 6:02 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10116014

RE: The Moki project. . .
One rotor 1st op done: There's about .0006" taper across the rotor's width when measuring the outside to outside swept arc. (the big imaginary circle this creates while spinning) .0006" taper isn't as close as I'd like but I'm going to live with it. I'm running my rotor clearance at .005" and case clearance at .008" so it shouldn't hurt anything. Twin lobe rotors aren't very efficient when compared to the multi flute helical setups in modern superchargers. I'll leave them alone for the time being and just stick with this. Progressing slowly, but dilligently. More to come. . . [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0005.jpg[/IMG]
Posted on: 11/5/2010 5:57 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10117529

RE: The Moki project. . .
Just got off the phone with the "Gawd" from MAC tuned exhausts. Were workin up a custom header and stinger for this bugger. Should be cool (hopefully, fingers crossed. . .) Here's a few more pics of getting the header set up sorted out. [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0004.jpg[/IMG] [IMG]http://i165.photobucket.com/albums/u64/nesikachad/RC%20PICS/moki%20project/Supercharger/DSC_0002.jpg[/IMG]
Posted on: 11/5/2010 5:54 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10117525

RE: The Moki project. . .
There! Sorry, camera settings were changed. Finished up the 1st op on the rotors last night. Now it's onto the 2nd op. So far so good. . .
Posted on: 11/5/2010 9:42 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10116778

RE: Sundowner 50 Arf
I look forward to meeting him! Name's Chad. I have a machine shop (I build rifles) in Sturgis. Working on a couple "pet" projects right now. First is my own 80cc twin nitro engine for my USRA 42% Kelly F-1 Pro plane. The second is a roots supercharger for my Moki 210 stuffed in a H9 sundowner. bummer that H9 quit making the plane and that USRA eliminated the class. It's just my "franken plane" now. Were working with the sturgis school board and the city about securing a piece of property just east of town for a dedicated field. The city is 100% on board with it and agreed to giving us a 500' x 75' paved runway. Good times! Chad
Posted on: 10/29/2010 6:21 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10103038

RE: Sundowner 50 Arf
I have a 91fx in my 40 size voodoo mustang. Speeds are good but it's quite a bit of weight for such a small plane. If I were to do it again I'd be more apt to stick another 60 Jett sport engine in it. That's what I have in my 50 size SD and it runs really, really well. A 10x7 master air screw gives me the best performance on 15% powermaster. I live at 3500ft elevation. Most guys seem to like the 9x6 or 9x7 apc. I really encourage anyone building a speed plane to use a Tettra bladder tank. the improvement is considerable. At $25 bucks they are well worth the $ IMO. If your going to mimic pylon stuff I say go one further and fabricate hard lines for fuel and pressure. In a corner you might experience 20+ G's. That means that little 6-7lb airplane suddenly weighs 120-140lbs. It also means that one ounce of tubing with fuel suddenly weighs 20 ounces. The silicone tubing WILL flex and I was plagued with an engine starving for fuel in the corners till I upgraded to hard lines. Then it all went away. . . Last, you'll find this plane suddenly develops quite a bit of "dihedral" in the corners as well. Either upgrade to a carbon spar or reinforce the aluminum one with a rib of plywood down the inside. Much happier plane when banking hard. The firewall sucks. There's a few You Tube vids of guys ripping their airplanes apart in midair due to the engine tearing the firewall off. It's worth going over. Especially with an engine as big as the OS91 FX. Remember, that 19.3oz engine suddenly weighs 25lbs when cornering. Good luck!
Posted on: 10/27/2010 11:06 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10097513

"Extreme" speed doesn't actually apply to me but. . .
. . .I have a 50 size Voodoo mustang that I stuck a 91os fx into. I have a 10x10apc on it and flew with it today. It's quite windy (20-30+) today in S.Dakota so it's hard to tell what the bugger is doing. Ran pretty good on the down leg side! Anyways, anyone have a good speed racer prop set up on this motor/plane combo? I'm running home brew 15% nitro/20% oil right now and it'll twist this prop at 13,800 on the ground. Only engine changes are removing the cone from the muffler and I'm using a Tettra bladder tank. I'm thinking 11x10, 11x11, or 11x12 even. (apc) Thanks! C
Posted on: 10/9/2010 3:22 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=10057916

RE: Sundowner 50 Arf
Big fly in this weekend in Sheridan WY. Bummer I can't make it. Lots of people there. Enjoy. C
Posted on: 9/10/2010 4:31 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9993114

RE: Revolver vs Sundowner?
I have a 50 SD with a Jett 60. Fun little plane. Speed is around 125-130 straight and level on a 9X6 or 9X7 APC on 15% powermaster. Some guys try like hell with a 91OS and in the end find its juts too heavy. This is what makes landing the tough part. With the Jett motor from ol Dubby it's a very docile plane on approach. Two things. IF you go with a Jett motor ditch the factory fuel tank. I know Dubby sells a bubble tank. I tried it and had issues. I like the Tettra version much better. If you aren't afraid of changes is a simple upgrade with a few dollars worth of carbon rod to hide the elevator horn inside the fuse. Easy job. Just make a horn from brass and solder to the U shaped wire they supply. Good luck. C
Posted on: 9/3/2010 9:27 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9977965

RE: My Sundowner 80
I have no doubt that Chuck (the sharp ol racer guy) that I'm working with gave me valid information. I worked in autoracing as a machinist during the 90's (part time as I was in the Marines at the time) and learned quite a bit regarding engine building (NHRA Comp Eliminator C altered, B altered, B street roadster, etc) Chuck is a smart fugger. There's something I'm not doing. My 2S knowledge is a bit weak so I'm thinking I may have measured the intake port timing wrong. He modified his combustion chamber a bit. I've yet to do that. I just stacked a few gaskets so that it'd tolerate the 30% fuel. That kills the quench area on the outer periphery of the piston so that may very well have something to do with it. I'm hesitant to post #'s only because I want to ensure this works first. I'd hate to see someone ruin an engine based on my bad scoop. This is what I know. Chuck has pretty much the fastest Moki powered 80" SD on earth. He literally ripped the wings off the thing. He has a 3 piece spar now. It broke right at the edge of the fuse where the wings attach. He was running his on 50% nitro at the time and was turning a 16X16 APC pattern prop at 9600rpm on the ground at 7500ft elevation. He has an Eagle Tree set up on the plane. His top speed on the straights was 169mph. That was on 40%. He's figuring he picked up about 5mph bumping the nitro content. (the last flight didn't have the Eagle tree set up) I have 2 gallons of nitromethane, 5 gallons of M-5 methanol, and a gallon of Klotz SuperTechniplate oil. I mixed a batch of 30% based on volume last week. I have a nitro hydrometer on order but it hasn't showed up yet. Hopefully this week it'll be here. It may just be that I have a piss poor batch of fuel, although I doubt it. I'm going to put a new ring in the motor when I tear it down. I used the old one as it looked really good and the piston/bore were in good shape also. If that doesn't work, I'll be ordering a new piston/liner and trying again. I am suspicious that I have something wrong with my intake ports though. I did raise the exhaust a bit. As time allows I'll post more. I'm not getting my arse kicked by a toy airplane!
Posted on: 8/24/2010 10:28 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9956381

RE: My Sundowner 80
Update. Well, turns out I was a bit optimistic. Remember the lack of experience comment?? I measured RPM with my Hobbico Intellitach from inside my garage. The florescent lights skewered the #'s I'm afraid. I'm no where near the target RPM. I've got some more work to do I guess. More to follow. C
Posted on: 8/24/2010 9:22 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9956249

My Sundowner 80" quest (Success!!)
I've probably wrecked more SD 80's than anyone. There's a reason why on my latest I left the #6 on the tail. The reasons are many, ranging from lack of experience to lack of skill. It's been a steep learning curve but I finally got it licked I think. I've been running a Moki 210 for the last couple years. The end goal is to have the skill set and setup to compete in the USRA Sundowner class. (For clarity, the USRA SD class allows for a Moki 210. Some port timing changes are allowed. You have to use a Bison Pitts muffler as well, no tuned pipes.) #6 has had quite a bit of fuel through it and it's still managed to stay in the air. So, I decided it was time to try and make it faster. With the stock engine the best I ever saw was 112-117 mph straight and level. This was on an APC 17x10 prop. It would turn 8600 rpm on the ground wih 10% powermaster. I met a guy down in the SW that's pretty much one of the most knowledgable guys around with high performance racing engines. He's an ME by trade and holds a few records at El Mirage dry lake in CA and Bonneville in UT. He's an avid racer and hell of a nice guy. he offered to share his Moki engine notes with me as he's an avid USRA racer. Lots of changes to crank and port timing. A few other little doo daads as well. I chewed on and massaged this engine over a couple weeks. I own a full CNC machine shop. All figures are on the ground with the plane strapped to a table. Tach used is a Hobbico Intellitach with a fresh 9V battery. The stock Moki turned a peak RPM of 7300-7600 on 10% powermaster with an APC 16x16 pattern prop. The "new" Moki turned a peak of 8600rpm on the same prop and fuel. Today I mixed up a batch of home brew 30%. I shimmed the head to dump compression a bit and I made (drum roll please) 9800-10,100 !!!!!! WFS BATMAN! I maiden this evening. If anyone tries this just remember: FUEL DELIVERY IS EVERYTHING. I'll get some pics up as time allows. C
Posted on: 8/20/2010 3:37 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9947901

RE: Sundowner 50 Arf
Ditch the fuel tank and get a Tettra bladder style. Well worth the 25 bucks. I won't use anything else. Your engine will love you for it. So will your wallet and airplane! I was able to hide the elevator linkage inside the fuse. Just machine, whittle, grind, saw a horn from brass and solder it to the wire thingy that ties the two elevator halves together. Then link a 1/4 or 5/16 carbon rod with dubro links and run a straight shot to your elevator servo. You'll have to cut a little bit of plywood off the back side of the servo trays. Reinforce with epoxy. I did the same to the rudder although it's not hidden. I used smaller 1/8 carbon for this. Move the tank up against the spar to keep the CG as neutral as you can as the fuel level drops. I'm using a 5.5oz Tettra. Good for 10 laps and a few high speed dives. My plane is sort of "purpose built" for a little club racing venture some buddies and I have begun fiddling with. Elevate the tank to get the fuel lines either even or above the carb inlet. This will prevent lean surges when cornering. I had to knock out a rib on my canopy. Reinforce the firewall a bit as its on the thin side. For cooling I chopped off the back half of the cowl cheek and blocked off the unused stuff. I run a Jett60 in mine. Hauls the mail pretty well I think. Easy to land this bugger. Much easier than the big brother 80 size. Good luck. C
Posted on: 8/12/2010 6:54 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9929488

RE: Sundowner 50 Arf
Wow! That's great news. I'm in Sturgis and we have a new (developing) RC club here with a 600' runway (grass) If he ever want's to come fly here he's more than welcome. No restrictions, exhaust, speed, turbine, the works. We cator to all of it! Chad
Posted on: 8/11/2010 8:03 PM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9927261

RE: Sundowner 50 Arf
Well, good news for Chad. My little SD maidened well last evening. Mine has the Jett60 set up like on Dubby's website. I've had a few of these planes and this latest is the best so far. TETTRA fuel tanks are the ONLY way to go IMHO. Rock solid! I have a 5.5oz tank. Good for ten laps plus a high speed dive or two. That's IT! so if you go this way just be mindful of your timers! Very compact, light, and easy to assemble. I had a Dub bubble tank before this. I didn't care for it all that much. Great engines!, but the tank isn't for me. I'm suffering a bit of a lean surge when banking hard in the corners but I have that sorted out now. Raised the tank to get level with the carb, switch to hard lines all the way to the needle valve/carb, and switching over from exhaust to crankcase pressure w/check valve to squeeze the tank. I learned a bit on the handling too. Finally got this bugger to corner the way I want. it'll bank almost like a formula plane now. It's all about CG and a little creative mixing with the elevator and ailerons.[:D] My engine is taching at 17,600 with a 9x6 apc. This was on 10% powermaster. I'll bring the 15% out this weekend and see if the speed comes up as the engine wasn't unloading in the air quite the way I wanted. It'd spin up really well in a dive, but sounded a little lethargic straight and level. I'm at 3600ft for elevation. Hoping that the snortier fuel and revised delivery setup will allow me to maybe bump up the prop to a 9x7 or maybe even a 9x8. We shall see. If any of you guys are coming to the Sturgis Bike Rally, BRING YOUR PLANES!! We have a field right outside of town with a 600' grass strip that's about perfect for little racers!
Posted on: 8/6/2010 10:31 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9914782

RE: Sundowner with a OS 95AX?
Probably pretty well. The speed threshold (from what I've seen) with this plane is somewhere between 130-145 mph (maybe 150 in some cases but I don't think it's done often) The OS/pitts combo is robust and easy to set up and run. The Jett60 (what I'm using) is a bit more work to get right but once running is also a very good combination. (a bit lighter) One trades RPM for brute "grunt" where's the other spins the snot out of the prop to get the speed. (A buddy's OS runs an 11" prop at about 13-14k wheres my Jett likes a 9x6 prop at almost 17k. One thing I have noticed on the OS is the fuel system. On the Dago he has a traditional tank setup where the exhaust drives the fuel to the engine. Towards the latter part of a flight the engine will begin to sound a bit "odd" at times like it's leaning out. I think it has to do with running at WOT and the aeration of the fuel from the exhaust. If possible maybe consider running a bladder style tank so that you can purge any air from the fuel system and have reliable fuel delivery. Maybe overkill, but it won't hurt anything.
Posted on: 7/21/2010 11:29 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9878817

RE: Sundowner 50 Arf
Well I'm getting closer to finishing my SD50!! I got the tail feathers on finally. I did something a little different for the elevator. I went with an internal pushrod setup for the elevator halves. I machined up a horn from brass and soldered it to the "U" shaped wire that connects the two elevator surfaces. From there I ran a DuBro link to a 5/16' hollow carbon rod and straight to the elevator servo mounted on the "driver's side" of the fuse towards the back where the canopy attaches. It should make for a very rigid setup that will provide very crisp elevator control. (hopefully) I'm using a true 1:1 linkage ratio so the resolution of the servo should be pretty linear. I plan on running some sort of pull/pull arrangement for the rudder. That servo is mounted in a tray that I made that mounts over the elevator in the centerline of the fuse. It worked pretty well on the last one of these I built. (I seem to go through one of these airframes each summer)-sucks! The Firewall is definitely in need of some reinforcement! I have a stash of thin Al angle stock that I plan to gusset the sides with and attaching with epoxy and 4/40 screws. I think it'll be a minimal weight increase while providing some solid rigidity in the event of a nose pick or prolonged vibration. I'm using a Jett60 like the one from the Jett website. Good times, good luck. Wish there were more guys around here into these planes so we could get some racing action going. I have a buddy with a Dago Red/OS 91 set up that's talking mad chit so it'll be interesting to see who takes the glory when this bugger is done.
Posted on: 7/21/2010 11:21 AM by Author "LongRifles Inc." in the forum "Extreme Speed Prop Planes"
http://www.rcuniverse.com/forum/fb.asp?m=9878804

RWB 100cc AW yak parts available
I've got wings, tail feathers, and a cowl(nib) that I'd like to get rid of for the 100cc AW Yak in the RWB color scheme. If interested send me a pm C
Posted on: 7/19/2010 9:48 AM by Author "LongRifles Inc." in the forum "Aero-Works Support"
http://www.rcuniverse.com/forum/fb.asp?m=9873861