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A question of weight.

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Old 11-14-2005, 08:40 PM
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Rebellion
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Default A question of weight.

Hi everyone,
My coming project for the year ( my Christmas present to myself ) will be a Q40, either a Vendetta or Polecat, to be powered by a Jett 50 for sport use. I have been looking around in here quite a bit and have seen the weight issue mentioned numerous times. I'm wondering just how critical the weight is on this type of aircraft, not just for speed but for overall flight characteristics. Reason I'm asking is I'd like to have a real nice paint job, but not if a few extra ounces will make the plane a dog to fly.

Thanks,

Dave
Old 11-14-2005, 09:37 PM
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Default RE: A question of weight.

Top speed will not be effected by an additional 2-3 oz of paint. Weight is really only an issue for accelleration on start up, and after a hard turn. As long as it doesn't weigh more than 4 1/2 lbs, you won't be sacrificing anything other than a slower spool up. Also, with a Jett .50 you will probably be spinning something a little bigger than 7.4" and that will help you on start up.
Old 11-14-2005, 09:46 PM
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Default RE: A question of weight.

Thank you Dave. Most appreciated ! Concerning the prop, Bob Brassel recommended an 8.8 x 9.25 cut down to 8" dia. for starters.

Oh, any words of wisdom on the Vendetta vs. Polecat choice? I know you've flown both.

Again, thanks,

Dave
Old 11-15-2005, 07:27 AM
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Default RE: A question of weight.

The only thing I would see, is a potential issue on CG with the PoleCat. Depending on how much more the Jett50 weighs in comparison to the Nelson40 that I run, you may have some trouble with being very nose heavy. I run my battery pack (500, 5cell) behind the rear wing bolts, and the servo tray is as far back as I can get it. But then again, I run my stuff pretty tail heavy.

Just some thoughts, DN probably knows more on this.?? I thought with the Vandetta, I had all the gear fairly far forward... Put a Jett50 in that and you might be able to put the battery behind the wing..?

It all depends on the weight difference between the motors.

rb
Old 11-15-2005, 09:32 AM
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daven
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Default RE: A question of weight.

Randy is right about the Polecat, I needed to put the battery behind the servo tray to get it to fly how I liked also. I did not like how it flew slightly nose heavy. I just weighed my Jett .50 and it with a prop and nut it came in at 1 lb 3 oz, so it is a couple oz heavier than a Nelson to start with. You may have issues with C.G. with that plane. With the Vendetta, they've balanced almost perfect just by stacking the receiver on the battery right behind the Tettra tank. There's really not much room to do anything different, but if you glued the battery in the oil cooler just behind the wing, that would help you out.

I have always liked the way the Vendetta handles in the air, I only had about 15-20 flights on my Polecat before a midair with Parker. I have another polecat on order to give a try next year.

I run a 10x7 on my Jett, and have been happy. I am currently designing an eindecker around my Jett .50 for our warbird race next year. Can't wait to pass the mustangs with a WWI plane.
Old 11-15-2005, 09:54 PM
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Default RE: A question of weight.

Thanks Gentlemen. It would seem that for my use, the Vendetta would possibly avoid a CG issue.

I have the black muffler on my Jett 50. Only ran it on the bench so far, but the sucker screams, although not in comparison to an all-out race motor like the Nelsons I'm sure. Perhaps the black muffler will save a tiny bit of weight on the front end as well.


Dave I like the Eindecker idea! Now that's gonna be cool. Funny, I have been thinking of kit-bashing a Lanier Dominator into something like what you're describing. There was a kit out several years ago ( don't remember too much about it ) that was built along similar ideas. WW 1 looks, but not scale, even had open structure aft of the wing, but used a thin airfoil and was a real " sleeper ".

Old 11-15-2005, 11:11 PM
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Default RE: A question of weight.

e-dave,

You nailed what I want to do with my Eindecker. I can't say too much more, the rules haven't been finalized for 2006, but I will have flying wires and a pilot

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