Originally Posted by Daryl Perkins

Tuomo, I had to switch to an 850 mah Life pack to get mine to CG, and it's still too stable.

I think that battery might fit in the gaps between the wing panels...........
i wondered what they were for........

Originally Posted by freddan2244

and also the installation of multi-locks for the wings...

What do you need the multilocks for? The easiest and cleanest and lightest and fastest way to secure the wing tips to the middle wing is to use tape. No need for multilocks.

Tommy

nevermind

Thank you all for your input.
I remember seeing an australian pilot talk about how his plane was slightly less stable than his closets competitors flying the same type and loosing out in a fly-off because he had to correct the unstable model vs the other pilot could let his plane fly more hands-off thus saving himself a lot of drag...
What I was after was to try the method of balancing the plane to perform well on a close-to-zero decalage (at least as close to zero as I could get it) The CG is at 125 mm right now and that seems to work out fine, if I throw the model straight and level into the wind it doesn't seem to require any up-elevator, trim or otherwise to settle on a reasonable glide-slope. I hope to test it some more this weekend.

Yes David Hobby.

Even if you are matching the cg to the tail rather than the tail to the cg, i still don't really see how hand tosses are better than flying at normal speed higher up tbh.

Also i think it is really hard to set the tail to fractions of degrees. What with finding the centreline of the aerofoil, flex in the tail etc.

Originally Posted by Daryl Perkins

Tuomo, I had to switch to an 850 mah Life pack to get mine to CG, and it's still too stable.

The 3.8 light carbon fuselage (white) is definately quite nice. Almost same tail moment as 4m fuse with much shorter nose. Still it balances slightly forward unless one uses very small nimhs (NAN foam tails are very light).

Originally Posted by Tuomo

The 3.8 light carbon fuselage (white) is definately quite nice. Almost same tail moment as 4m fuse with much shorter nose. Still it balances slightly forward unless one uses very small nimhs (NAN foam tails are very light).

Tuomo,

3-4 grams on the tail and you will be at 125 - or since you will no doubt be running ballasted 99% of the time (these planes are too lite!) you can just adjust with your ballast!

See you in 2014 maybe ?

I am waiting for the fall winter rain to quite long enough to go fly. My toys are stacked up and waiting ...I have a new fuse to build now so at least ill have something to do this weekend.

Originally Posted by webbsolution

3-4 grams on the tail and you will be at 125 - or since you will no doubt be running ballasted 99% of the time (these planes are too lite!) you can just adjust with your ballast!

Hmmm... I hate lead in tail, but substituting foam elevator with molded one changes CG 6-7mm if I remember right. Time will tell what CG I want to have.

Originally Posted by webbsolution

See you in 2014 maybe ?

That looks like a good project.

Originally Posted by satinet

Yes David Hobby.

Even if you are matching the cg to the tail rather than the tail to the cg, i still don't really see how hand tosses are better than flying at normal speed higher up tbh.

Also i think it is really hard to set the tail to fractions of degrees. What with finding the centreline of the aerofoil, flex in the tail etc.

Never said hand tosses are better than high-start for testing... It was just that I wanted to see that the CG-decalage-combination wasn't way off, kind of like checking to see that the elevator trim isn't way off... Besides, if things go horribly wrong it might not do as much damage from 10 ft as it would from 150 ft???

I am in no way saying that this method of setting the decalage close to zero is better than the more traditional way of testing. I just wanted to try it and to be honest I never expected the results to be any different, it's just another way to get there. It might take longer, or it might be quicker, I dont know until I've tried it. The optimum set-up will be the same regardless of how I arrive there, right? I read about this method on one of these forums and wanted to try it... Again, don't know if it's the best or the worst way of doing things. The one reason I didn't try the plane on the high-start was that I ran out of daylight since I tested the plane in the evening...

Today however I did try it higher up at the CG that I arrived at previously. It handles quite nicely though I don't know what the optimum cruise speed is, what thermal-speed is optimum etc since I only had a 65 meter line to launch with. I did to my amazement catch enough lift to maintain altitude for quite a while. It's only 5 degrees centigrades, or 41 F for you guys across the pond... Also did some rolling side to side to see how much adverse yaw I get, did look like I have enough differential and aileron-rudder coupling. I only had time to try it in normal mode though...

Do most of you guys use any aileron-flap mix in thermal and launch mode? The more I think about it the less certain I am of wether or not it's a good idea to have it turned off during launch.

I am going to have to get more flap deployment though. Whom ever said you can never have too much flap-angle on these planes were right.

Originally Posted by Tuomo

Hmmm... I hate lead in tail, but substituting foam elevator with molded one changes CG 6-7mm if I remember right. Time will tell what CG I want to have.



That looks like a good project.

Yes that would be really cool to finally meet you and a host of other people in Europe. And it will be a funny position then because you will have come to the "dark side" and you will be flying a SL 3.8 oh and I will be quite comfortable flying at 3100 grams ! complete change of positions

But there are a lot of targets to smash before I can get there. We have to plan our TS - and it would be nice if just for once I actually make the team lol. I have been to two WC now as the 4th pilot but due to other scenarios I ended up flying. So my goals this season are a little more down to earth.

Anyways back to the X2 conent - I have a new fuse courtesy of Nan models to build. I use the ATX 761 servos and the cut outs are a little large for those servos so ill be making some kevlar plates as mounting brackets to span the gap.

No other build deviations - I should have this ready for testing by the end of the weekend but I dont anticipate an end to the rain for a month. I might have to take a model with me to Chicago in order to test it.

My 4m X2 is about ready for flight, just need to program the radio. A flying weather is also needed, not so easy at this time of year.

Specs: balance point now at 119-120mm, weight 2050 grams (about 72,2 ounces). At this balance point it needed 58 grams of nose weight.
No SL, more of an everyday plane that also survives those not-so-good landings + winching/towing in 5-8 m/s wind.

Servos: in wings Futaba 3171SB (s-bus version of the 3150). Elevator Graupner DES658, rudder Futaba 3155.

Receiver: Futaba 6203SB.

Battery: Hyperion LiFe 1450mah, with Powerbox 5.9V regulator. The wing servos are fed directly from the battery/regulator, not through receiver.

On wing I use the s-bus system, for the first time. The wing wiring was very easy to do!

Tommy

Originally Posted by Tommy Wee

What do you need the multilocks for? The easiest and cleanest and lightest and fastest way to secure the wing tips to the middle wing is to use tape. No need for multilocks.

Tommy

Tape is not the fastest method: nor is it particularly environmentally-friendly... I love multiloks: nothing extra you have to make sure you carry with you: click-and-go...

Chris

Originally Posted by Woodstock 1

Tape is not the fastest method: nor is it particularly environmentally-friendly... I love multiloks: nothing extra you have to make sure you carry with you: click-and-go...

Chris

How do multilocks survive in hard landings?

Originally Posted by Tuomo

How do multilocks survive in hard landings?

They pop out, much like tape splits...

Originally Posted by Woodstock 1

They pop out, much like tape splits...

My tape does not split I use a piece (about stamp size) of fg-tape close to hinge line.