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Old Nov 09, 2012, 09:11 AM
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I started at 15% (5.5") and tried thru 25% (6") as per the calculator. I think I'll be building a 2" tube to really get the battery out front, just like you said, and start moving it back until it stops acting funny.
Just curious, did you include the ailerons as part of the calculation?
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Old Nov 09, 2012, 09:19 AM
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Originally Posted by viper522 View Post
I started at 15% (5.5") and tried thru 25% (6") as per the calculator. I think I'll be building a 2" tube to really get the battery out front, just like you said, and start moving it back until it stops acting funny.
Viper you should be moving forward from the 15% point NOT next to the 25% point (since tail heavy planes are much harder to control than nose heavy).

Also in the calculation you should also include your control surfaces!
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Old Nov 09, 2012, 09:19 AM
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Originally Posted by viper522 View Post
I started at 15% (5.5") and tried thru 25% (6") as per the calculator. I think I'll be building a 2" tube to really get the battery out front, just like you said, and start moving it back until it stops acting funny.
Going from 15% to 25% is going in the wrong direction.
If its unstable at 15, it will be even more unstable at 25.
I think adding a pod will help a lot, but keep in mind, that any fuselage no mater how long or short, does not change the need for the correct CG.
In other words, the correct CG would be the same with or without the fuse.
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Old Nov 09, 2012, 09:20 AM
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Going from 15% to 25% is going in the wrong direction.
If its unstable at 15, it will be even more unstable at 25.
I think adding a pod will help a lot, but keep in mind, that any fuselage no mater how long or short, does not change the need for the correct CG.
In other words, the correct CG would be the same with or without the fuse.
Haha Gordo look at the post above you ...we were typing about at the same time :P
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Old Nov 09, 2012, 09:30 AM
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Originally Posted by rimshotcopter View Post
Just curious, did you include the ailerons as part of the calculation?
No, just the wing itself.

Quote:
Originally Posted by msev View Post
Viper you should be moving forward from the 15% point NOT next to the 25% point (since tail heavy planes are much harder to control than nose heavy).

Also in the calculation you should also include your control surfaces!
I know the 15-25% progression is getting away from naturally stable and more toward advanced, but I was trying anything anybody could come up with at the field.

If I include the control surfaces in the CG calc, it moves the recommended CG point further aft (from 5.5" to 5.8" at 15%) due to the longer chord. That's opposite what everyone here is telling me - move it forward. My root/tip chord is 8.75" without including the 2" elevon, 25deg sweep.
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Old Nov 09, 2012, 09:31 AM
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Haha Gordo look at the post above you ...we were typing about at the same time :P
Great minds think alike.
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Old Nov 09, 2012, 09:36 AM
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Originally Posted by viper522 View Post
No, just the wing itself.



I know the 15-25% progression is getting away from naturally stable and more toward advanced, but I was trying anything anybody could come up with at the field.

If I include the control surfaces in the CG calc, it moves the recommended CG point further aft (from 5.5" to 5.8" at 15%) due to the longer chord. That's opposite what everyone here is telling me - move it forward. My root/tip chord is 8.75" without including the 2" elevon, 25deg sweep.
Add the fuse and move the CG further forward. That's about all I can say at this point.
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Old Nov 09, 2012, 09:38 AM
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Add the fuse and move the CG further forward. That's about all I can say at this point.
That's what I'll be doing If it survives the trial I'll be back to discuss my findings. Considering how many times it has already been plowed into the ground, I don't think survivability will be a problem.
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Old Nov 09, 2012, 09:40 AM
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Add the fuse and move the CG further forward. That's about all I can say at this point.
+1


On an unrelated matter, do any of you guys have experience with Correx (Coroplast)? It makes for undestructable, although heavy wings..And one can use Ed's technique in making it..I might try and make an Alula clone out of it.
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Old Nov 09, 2012, 09:49 AM
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+1


On an unrelated matter, do any of you guys have experience with Correx (Coroplast)? It makes for undestructable, although heavy wings..And one can use Ed's technique in making it..I might try and make an Alula clone out of it.
Someone made a wing from Coroplast on another site, it doesn't want to form the airfoil, so he had to cut each vein parallel to the bend.
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Old Nov 09, 2012, 09:53 AM
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Better 200w 5.8ghz FPV kit?

Guys, I'm trying to retrace my steps and find something I lost.

I've recently seen a post, pretty sure here at RCG, on a "better" entry level FPV kit, with similar specs to the entry level HK 5.8ghz 200w kit, but reported to offer much better range in practise. I just can't find it again. This is for my FSU Axon currently under construction. With the HK gear currently in stock I'm feeling a bit of time pressure. I really don't want to buy the HK kit until I've found and reviewed that other kit.

I know we get a bit of FPV chat here as it pertains to our FSU models: if the above rings a bell, please let me know...

Thanks!
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Old Nov 09, 2012, 10:01 AM
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Here are a few pictures of my airfoil created from $Tree foam board for a VTOL Build under construction. I opted not to use tape and will use foam safe paint for now however, I am looking for a better way to seal the surface.
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Old Nov 09, 2012, 10:06 AM
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Originally Posted by syzygyQ View Post
Guys, I'm trying to retrace my steps and find something I lost.

I've recently seen a post, pretty sure here at RCG, on a "better" entry level FPV kit, with similar specs to the entry level HK 5.8ghz 200w kit, but reported to offer much better range in practise. I just can't find it again. This is for my FSU Axon currently under construction. With the HK gear currently in stock I'm feeling a bit of time pressure. I really don't want to buy the HK kit until I've found and reviewed that other kit.

I know we get a bit of FPV chat here as it pertains to our FSU models: if the above rings a bell, please let me know...

Thanks!
ImmersionRC offers a 5.8GHz 600mW setup similar to the HK stuff. Maybe that's what you're thinking?

http://www.readymaderc.com/store/ind...roducts_id=266
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Old Nov 09, 2012, 11:43 AM
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Thanks, we tried trimming the elevons up, moving the battery around, throwing it hard/soft. It was like throwing an empty pizza box into the wind - it just went random directions until it met the ground - and no further than 25ft away. The good news is that it probably hit the ground at full throttle, right after launch, at least 2-dozen times and merely creased the DT foam under the tape. No actual damage!

Here it was ready for maiden
How big is that motor? and what is your prop? you could be underpowered a bit too
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Old Nov 09, 2012, 11:46 AM
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How big is that motor? and what is your prop? you could be underpowered a bit too
3s 2200 lipo
Tried a 9x4.7 and 8x4 folder
1050kv outrunner
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