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Old May 11, 2012, 11:53 AM
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blunight's Avatar
United States, FL, Cape Coral
Joined Aug 2008
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Quote:
Originally Posted by scottdearinger View Post
the control rod connectors are the most important- the stock ones just plain suck and are prone to failure....
+1 on that! Replace the stock components and leave the excess control rod length - Youll need al that length if you plan on replacing the stock servos some day as different servos (HS65HB's in my case) need slightly different mounting locations.
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Old May 11, 2012, 04:21 PM
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Old May 11, 2012, 07:09 PM
Tossing planes into the snow
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The pictures posted this morning by skyhawk got me thinking. The first calm day we have had in 2 weeks also got me flying. I wasn't thinking about CG but about power. Usually I use 1300 batteries because they get me up there and it's nice to be light.

What I wanted to know, was if a bigger battery would provide a noticeable increase in power and it did. With an 1800 30c battery it went almost straight up with the stock prop, even with the weight increase. The difference in CG was apparent when gliding however. I have that plane trimmed to glide for long periods of time hands-off. With the 1800, it was porpoising and 3 clicks of down elevator took care of that, but it was moving faster than usual. Maybe next time I will try it with a bit of weight on the tail.
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Old May 11, 2012, 07:50 PM
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Ireland, Cork
Joined Oct 2010
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Quote:
Originally Posted by Radio.Active View Post
Wow... amazing how little the CG is shifted. You forced me to check out mine to confirm your results and they are quite similar to your 6mm difference < 1/4" Mine was closer to 1/4" or just a bit over going from the smallest to largest LiPo. I'm able to get my Turnigy 2200 fully into the battery slot with a little force.

Turnigy 1300mah 20-30C 3S 115g
Turnigy 2200mah 20-30C 3S 185g

So the bottom line for me is to not hesitate moving to the larger battery as it gets windier and not worry about the CG shift forward. Both the weight increase and very slight move of CG forward 1/4" should work to my advantage.


I'm able to get my Turnigy 2200 fully into the battery slot with a little force.
I never force something big into a slot (or should that be slut)
I ask her first... LOL



I'd never checked the CG on my stock radian and was quite shocked to see that the CG was at 80mm with the 1300 Li-Po even though it does fly fine ..

So I'm now going to do the same CG balance test again with my Decalage Moded Radian as after I finished the Decalage mod I did check the CG and I'm sure that was 80mm with the 1300mAh Li-Po , even with all the fiber tape taped to the rear fuse..

What is the CG for a Stock Radian in mm ?

Sean.

.
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Old May 11, 2012, 08:20 PM
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Old May 11, 2012, 08:20 PM
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Philadelphia, PA
Joined Jan 2002
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Stock CG location

Center of Gravity Location
The center of gravity on your Radian should be located
approximately 2-1/2 (63mm) behind the leading edge
of the wing, when measured against the fuselage. This
CG location has been determined with the ParkZone
1300mAh 11.1V Li-Po battery installed.

Right out of the Radian manual.
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Old May 11, 2012, 08:25 PM
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Old May 11, 2012, 11:35 PM
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Here is my new Radian.

I live in the east part of San Diego and just maidened this
in "semi" stock form.

I did replace the tail feather connects with the DuBro micro's.
I also glued a cf torsion plate in the aft fuse behind the rx bay...
Repositioned the elevator horn. Added paint to top and bottom...








After a couple of landing attempts, I too, sumized flaps would
be in order...









I glued an outrigger to protect the deployed flap, gettin about an inch of clearance.




Its a fun ship !



Here's some fun from Torrey ~ !

Aint nothin better than bein the only RC pilot on the mound on a gray Monday at Torrey Pines !

Cloudy days and Mondays always make me smile - especially flyin at Torrey Pines (3 min 13 sec)
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Old May 12, 2012, 04:07 AM
Not a newbie anymore..
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Ireland, Cork
Joined Oct 2010
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Quote:
Originally Posted by Radio.Active View Post
2.5" in my manual = 64mm

My 2 Radians ( with and without decalage fix ) one with aluminium hub and tail weight, one with heavier DIY HStab, both with CF arrow in boom, CF rod in VStab, Gold N Rods yada, yada, yada ; both have the aprox > 1/4" variance in CG between 1300mah and 2200mah.

The non-dec goes from 2.5" to 2.25"
The dec version goes from 3.0" to 2.75"

As I always fly with a 808 cam and 850mah 1S external LiPo velcroed to the top of the wing saddle near the CG I can still easily move the CG aft by repositioning that battery.
Thanks..

I'm gonna try the 2100mAh Li-Po next time I go flying my stock Rad...

.
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Old May 12, 2012, 04:08 AM
Not a newbie anymore..
skyhawk newbie's Avatar
Ireland, Cork
Joined Oct 2010
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Quote:
Originally Posted by Caddguy6 View Post
Center of Gravity Location
The center of gravity on your Radian should be located
approximately 2-1/2 (63mm) behind the leading edge
of the wing, when measured against the fuselage. This
CG location has been determined with the ParkZone
1300mAh 11.1V Li-Po battery installed.

Right out of the Radian manual.
I'd lost the manual , along time ago...


.
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Old May 12, 2012, 07:11 AM
Chess club geek with wings
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United States, FL, Cape Coral
Joined Aug 2008
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STEELINOX: How about more details on your flap mod ie: material you used, etc. and how does it fly now vs before the mod? I've been considering the same mod only I'd perfer the flaps cut into the wings so I could put both up to act as spoilers - any thoughts?
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Old May 12, 2012, 10:17 AM
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Quote:
Originally Posted by blunight View Post
STEELINOX: How about more details on your flap mod ie: material you used, etc. and how does it fly now vs before the mod? I've been considering the same mod only I'd perfer the flaps cut into the wings so I could put both up to act as spoilers - any thoughts?
My "split flaps" do the job. These are 1" x 12" x 1/32ply. Covered with mylar tape and tape hinged.

I have them set to RS switch and mixed.

When deployed they work great, slows it down .

I used split rather than cut into the wing. Its "keep it simple" good.

The position I used for flaps will prolly not be good for spoilers.

Spoilers work best on the CG line top of the airfoil as I understand it, breaking the main lift of the airfoil.

I thought to set up spoilers too, but, then its adding weight [vs split setup] and cutting into my spar area - not good !

Thanks,
Randy
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Old May 12, 2012, 10:57 AM
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My radian nose dived about 8 feet after hitting a tree. It compressed the front part of the fussalage foam a little. Nothing major, probably about a quarter inch of compression. Is there any method to getting the compression out?
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Old May 12, 2012, 11:17 AM
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Old May 12, 2012, 11:22 AM
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Quote:
Originally Posted by qwerty11 View Post
My radian nose dived about 8 feet after hitting a tree. It compressed the front part of the fussalage foam a little. Nothing major, probably about a quarter inch of compression. Is there any method to getting the compression out?
I read somewhere here that hot water works to re-form this sort of thing.

I'd of course pull everything and then do it, so, motor, cowling, electronics, its all gotta come out...
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