putting your plane on a diet
 

what are the most effective ways of losing wieght in a ship, that's built and is overwieght?

I just bought a an old bolly lotus that's going to be my test bed for a mvvs setup till I can get my own ship up and running and the previous owner was complaining of the wieght.

What can I do to get it lighter?

It's a fibreglass fuse, with foam wings that have all been covered in glass.

It's stipped of paint, and I'll take pains to get that light, but apart from that, what else can I do?

RE: putting your plane on a diet
 

How much weight are you talking about ...

Scott Anderson
Team Castle Creations
Team Tanicpacks

RE: putting your plane on a diet
 

I just weighed the airframe, and considering the size of it, it's overwieght.

2300g as a bare airframe.

I'd like it lighter if I can.

For the record, the Lotus is 73" and has about 930 squares.

RE: putting your plane on a diet
 

Well I took nearly a full pound out of my Impact with the following:
1. Change the wing tube to a carbon tube from Jerry Budd
2. Changed the exhaust from a 2c hatori pipe to a carbon Aeroslve pipe
3. Had Ryan M. build me a new nose ring and use the Hyde mount w/o the nose ring integrated with it.
4. Use light wheels

All the little items you don't give much thought to really add up in a hurry if you change them all.

Good luck!

Joe W.

RE: putting your plane on a diet
 

Servo selection can make a huge difference. I'm in the process of losing some weight on my Genesis and by changing out my aileron servos and my throttle servo I will get 3 oz. off the plane. Mike

RE: putting your plane on a diet
 

All of the above plus: Check out servo trays in the fuselage, tank mounting and hold downs, pushrods, fittings, etc. Changing materials and judicious use of lightening holes can shed weight. Moving things around to change CG can allow dumping of ballast whose only funtion is to balance the plane (and make it heavier). It's amazing how much can come out of a plane -- a few grams here and there add up.

Good luck with it!
Tom

RE: putting your plane on a diet
 

Well, suprisingly I didn't notice before but the wings and tail are all honeycombed. SO I don't think I can shave a lot of that.

The structure inside is a little higgedly piggedly, and I'm tempeted to tear out the servo trays and replace them with a a carbon one.

The wing joiner is a good idea also, so I'll look into that if I need to shave some more out.

Mike, what servos are you using to shed some of that weight?

RE: putting your plane on a diet
 

Also dump the nicad and use a 2 cell lipo 700 mah and a voltage regulator.. that will help.. Light weight spinner and lighten back plate..


Fill wings with helium... <vbg>

Scott Anderson

RE: putting your plane on a diet
 

Don't forget to trim all your fasteners to the minimum length needed and substitute aluminum or titanium for steel where you can.


Mark

RE: putting your plane on a diet
 

I was thinking of going for a lipo pack.

acutally that's a good thing

time for another thread....

RE: putting your plane on a diet
 

I bet a lot of weight is coming from the layup of the airplane and the glassing on the wings. If the builder didn't seal the balsa before he glassed it, chances are that it soaked up a whole bunch of weight in epoxy in the wood. Since it's a test bed, I don't think I'd go super crazy about it, but lighter does fly better (to an extent).

RE: putting your plane on a diet
 

Especially concentrate on any metal parts in the tail, since removal here will allow weight to be taken out of nose as well. I make my control horns out of sheet phenolic and glue them into rudder & elevators (and ailerons too). An ounce from the tail saves another three in the nose. Still searching for a strong but light steerable tailwheel.

RE: putting your plane on a diet
 

Mike, what servos are you using to shed some of that weight?
[/quote]
Hey Renegade I have JR 8231's in the ailerons and throttle. I'm going to put 9411's in the aileron and probably use a Hitec HS81MG in the throttle. That will save about 3 oz. Mike

RE: putting your plane on a diet
 

Glad to see I'm not alone regarding this; it floors me everytime I see a 1/2-3/4" extra hanging out of a nut or mounting point. Drop washers where you don't need them, too. Button head cap screws I use almost exclusively which provide both a larger bearing area and look better (IMO). Those crazy lock washers everyone uses are... Crazy. Add weight and really don't provide much in the way of locking. Loctite used in conjunction with clean threads will solve just about any loosening problem you'll encounter. How about those axles with a 1/2" hanging out past the collars? (The whole axle/collar business is pretty crude, IMO- E-clips or other means are much lighter and cleaner). How about those engine mounts with an 1" hanging out past the front of the engine? Trim 'em. I always attack the highest density offenders before resorting to more elaborate (and expensive!) methods/materials.