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Giant Scale Corsair weight Top FLite

Old 03-28-2014, 11:21 AM
  #26  
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I would go with the G62 that you have. A 53cc twin is probably equivalent to a 45cc single. At your altitude that's marginal at best.
Old 03-28-2014, 01:53 PM
  #27  
Warbird AL
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Lots of great suggestions. I do appreciate the comments. I will let you know how it turn out . Hopefully a positive result, I almost said end, sort of like never say I am going up one more time...
Old 03-28-2014, 02:24 PM
  #28  
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Hey Al - where do you fly at?

Keith - Grantsville..........
Old 03-28-2014, 02:53 PM
  #29  
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I have this kit on my shelf. Is the SAito FA 450 radial to big/small for this kit (Nitro) ?
Old 03-28-2014, 05:40 PM
  #30  
Warbird AL
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"Tail end charlie" I like it! Keith, I fly down at the Utah Valley Airfield in Lehi or now I think Saratoga Springs owns it. I don't know if the Saito will fit, I dont know the dimensions on it. If you got it I can measure.
Old 03-28-2014, 06:29 PM
  #31  
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Anyone know anybody that has a GS corsair with a dle 55 in it?
Old 03-28-2014, 10:53 PM
  #32  
fw190
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In all my radial warbirds, I build a box mounted to the firewall just above the motor, it holds all 3 batteries and in front of it I bolt on or pour in lead shot mixed with epoxy.

This 1/4 scale LA-7 required only 2 lbs of nose weight, even with full details. My smaller Bearcat required no weight at all with this method.

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Old 03-29-2014, 03:58 AM
  #33  
rt3232
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Fw193

That is about what I have been doing, but just mounter to the motor box.

I will incorperate it into the firewall on next go. Thanks for sharing

Cheers bob T
Old 03-29-2014, 05:02 AM
  #34  
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Put a helium balloon in the tail
Old 03-29-2014, 08:17 AM
  #35  
radiisteve
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High Guys Just seeing this post on balancing and have a couple ideas to share. I've been balancing Medical Linear Accelerators and Airplanes for 25/45 years and with some simple math we can perhaps add "less weight for the same effect."
Your message said ( I did a rough balance and I need another 6 lbs weight in the nose to balance her out.),
· So if you have the engine, muffler, prop and a nut?? HH Nut?? and it takes 6 lbs to balance at mid cowl (setting weight on it),
· Then going out to the inner cowl diameter (estimated 20 1/8" from CG scaling the plans pdf as compared to approx 16 3/8" to mid cowl) you'd only need 4.88lbs to balance.
· The Moment Arm Formula is simply weight X distance = Moment Arm force (or effect if you will = MAE).
· If you add a "Really Big Prop Nut" from Harry Higley (roughly 8oz. compared to the STD Big 4oz prop nut), you can reduce the front cowl weight to approx 4.27 Lbs and save more weight overall.
· W x D = MAE (weight x Distance = Moment Arm Effect called MAE)
· Having a MAE number calculated, you can always divide that MAE by a different desired placement (measure distance from CG), and simply divide the previous calculated MAE by the desired location distance to get a corrected weight required for the same balancing effect.
· End effect, 6lbs @ 16 3/8” (mid cowl) = 98.25MAE.
· So when we review the front edge cowl placement (20 1/8” from CG), and divide 98.25MAE by 20 1/8” we get a revised weight of 4.88lb required to balance.
· Add the effect of the “Really Big Harry Higley Prop Nut”, and you reduce the weight needed to approximately 4 1/4 lbs required to balance the plane. That’s almost two pounds less (1.75 lbs. or 29.17%).

Good luck with your Corsair!
Old 03-29-2014, 08:36 AM
  #36  
radiisteve
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I looked up a 53cc twin engine on line (hobby king) weighing 1477g = 3.25 lbs, and comparing to a G-62 with eng, muffler, Ign & mount weighs 5.125 lbs, for a 1.869lbs. addition weight. This additional 1.869 lbs would reduce th front cowl eight to 3.28 lbs, but you would have added an additional 7/8ths of a pound to the plane.

So in this case, the math shows positive and negative effects without the hours of mounting then re-weighing. Yes in Engineering we try to do most of the work on paper first to make manufacturing efficient.

For you the airplane builder and flyer, the object would be to save you time, money and auguring out the plane and finding out it didn't work. A little work on paper can save you hours of trial and error efforts.
Old 03-29-2014, 08:49 AM
  #37  
Chris Nicastro
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I redesigned the cowl mount because the stock one is inadequate. After a few flights I was always chasing tightening screws and in two cases the cowl got loose in flight and rubbed the back of the prop. So out with the stock set up and in with the redesign.

I'll self edit my previous suggestion and say use lead shot in the cowl ONLY if you mod the cowl mount.
Ive posted my work on this before but if your interested I can find my post and link it.
I split the cowl from the cowl flaps and made the cowl ring stand off 0.75 inch forward of the firewall. The taper of the cowl requires the ring to be resized slightly. The cowl ends up in the same location relative to the fuse but now the cowl has button head screws radially installed into the wood ring.
The cool part is the screws look good enough, minimally noticeable, and access is easier. I would suggest making a copy of the cowl ring in a proper marine plywood because the supplied wood is crap and delaminates with a stare! Lol
Old 03-29-2014, 09:04 AM
  #38  
Corsair2013
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The problem is that moving the weight out to the front edge 20 1/8" you have issues with the cowl vibration and coming loose. As mentioned, unless you have a really heavy duty cowl, or special mounting, that is not the best place to mount the weight. So that leaves you back at less than mid cowl - motor mount area.

If we could just make the props out of lead or heavy steel and the motor could handle it then our problems would be easy to fix...................

K


Originally Posted by radiisteve
High Guys Just seeing this post on balancing and have a couple ideas to share. I've been balancing Medical Linear Accelerators and Airplanes for 25/45 years and with some simple math we can perhaps add "less weight for the same effect."
Your message said ( I did a rough balance and I need another 6 lbs weight in the nose to balance her out.),
· So if you have the engine, muffler, prop and a nut?? HH Nut?? and it takes 6 lbs to balance at mid cowl (setting weight on it),
· Then going out to the inner cowl diameter (estimated 20 1/8" from CG scaling the plans pdf as compared to approx 16 3/8" to mid cowl) you'd only need 4.88lbs to balance.
· The Moment Arm Formula is simply weight X distance = Moment Arm force (or effect if you will = MAE).
· If you add a "Really Big Prop Nut" from Harry Higley (roughly 8oz. compared to the STD Big 4oz prop nut), you can reduce the front cowl weight to approx 4.27 Lbs and save more weight overall.
· W x D = MAE (weight x Distance = Moment Arm Effect called MAE)
· Having a MAE number calculated, you can always divide that MAE by a different desired placement (measure distance from CG), and simply divide the previous calculated MAE by the desired location distance to get a corrected weight required for the same balancing effect.
· End effect, 6lbs @ 16 3/8” (mid cowl) = 98.25MAE.
· So when we review the front edge cowl placement (20 1/8” from CG), and divide 98.25MAE by 20 1/8” we get a revised weight of 4.88lb required to balance.
· Add the effect of the “Really Big Harry Higley Prop Nut”, and you reduce the weight needed to approximately 4 1/4 lbs required to balance the plane. That’s almost two pounds less (1.75 lbs. or 29.17%).

Good luck with your Corsair!
Old 03-29-2014, 09:29 AM
  #39  
DCORSAIR
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Wagon1

I used a Saito 450R in my 32lb Byron Corsair. Flew great but I did have to cut two holes in the cowl for the bottom cylinders, it will fit but by the time you offset the thrust and I didn't want the top cylinder to be showing so I dropped the motor down just enough to clear the top cylinder. Didn't look bad at all, you could barely see the vavle covers. Don't know if the TF Corsair is the same size cowl??? Even with the big Saito 450 up front I still had to add weight. The sound is awesome and you can use the flex pipes to route the exhaust where needed.
Old 03-29-2014, 10:03 AM
  #40  
c550
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I am in the finishing stages of the Top Flite GS Corsair. I am using the Saito 450R3 also. I found that the fiberglass specialties cowl just fits. I am almost to the point of mounting the engine and seeing how much weight I need to add. Just need to do some weathering and markings and clear coat and details and a few other things!
Old 03-29-2014, 10:30 AM
  #41  
DCORSAIR
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c550

Your not going to believe the thrust that Saito 450 puts out. I kept mine in the 6500-6800 range with a 22x10 prop and we clocked my 32lb Byron Corsair at 98mph in a low level pass. Also try to use a onboard glow system so you can run it rich, I failed to do that and after about 30 flights or so one of the cam gears let go, landed on 2 cylinders but I think it was from being lean so I wouldn't have to run an onboard, crazy thing was, I sent the motor in to Horizon for repair and they didn't have the parts to repair it so they sent me a brand new engine, really don't know if it was my fault or this was a problem with that motor, I never asked.
Old 03-29-2014, 01:55 PM
  #42  
c550
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DCORSAIR

What size tank did you use? I have a40 oz and i am wondering if it will be enough.

regards,

Dave
Old 03-29-2014, 05:07 PM
  #43  
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In the early priming/sanding phase of my Top Flite Corsair. I am using a 450r as well and am hoping to keep the empty weight around 30 lbs. That may be wishful thinking. I'm waiting on my Keleo exhaust ring. I need to mount the muffler before I can build any battery trays up front. I'm also ordering a CH Ignition system, so I can add that weight up front. Using 32 oz. fuel tank. Hoping to run a 24x8 Falcon prop.
Old 03-29-2014, 07:52 PM
  #44  
DCORSAIR
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I also used a 32oz tank. I didn't use ignition or onboard glow system, to start it I just soldered up three of those remote glow drivers into one lead, then used a Hobbico 4500mah glow igniter to light all three plugs at the same time. Every now and then if you idle to long it will drop the bottom left cylinder, I never lost more than one cylinder though. To tell you how much torque that motor has , when I lost a cylinder just after take off, I was able to fly the pattern on the other two cylinders and at 32lbs I was a little nervous about a stall but the Byron Corsair with full flaps will almost fly itself in on final, loved that plane and wish I would have never sold it.
Old 07-18-2014, 07:27 AM
  #45  
Warbird AL
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Ok, good news. First it barely got off the ground with the 52. Flew about 5 feet then decided it didn't want to stay in the air. damage was a broken prop and destroyed the landing gear. Picked up some new gear and put the G62 in it. G62 with a 22x10 wood prop.

Yesterday was awesome. I flew her 3 times and it was solid in the air!. The landings were watched by several people including 2 (real) pilots. Both said I was mushing it in on the approach. they both thought it was going to stall. The plane came in nose high. We figured I must have been making my final approach too low so there was no way I could put the nose down. It was sloppy but it landed ok. I will try to come in higher on my final approach and let it sink in. The good thing is she showed no bad habits.

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