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Old Jul 22, 2014, 09:12 AM
The "Foaminator"
mikeruth's Avatar
United States, CA, Los Angeles
Joined Mar 2007
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Originally Posted by hinterkress View Post
Hi All,
I haven't seen this mentioned in the thread, apologies if I missed it. I have a new RP which I put together from components bought separately from my LHS i.e. wings, fuse and v. stab. I also used the recommended 10mm cf spar tube. On 2 occasions now both wings have suffered significant flutter on the leading edges pulling out of larg-ish loops (power off). The amplitude was something like 40-50mm. The wings seem to be as rigid as my previous ones and there isn't any slack between servos and control surfaces so I'm at a loss to find the reason especially as I'm flying it the same way as my original RP which never had this problem and it had the fg spar tube. Anyone else had this happen?

John
Very odd indeed when given all other factors APPEAR to be the same.

If you want little background and reading check this http://www.rccr1957.com/flutter.pdf.

Not sure if this will lead you to a fix but it's a short read.

One quick thought and possibly a fix is to tape up the hinge gap and test.
I know others say this doesn't help but indeed I have seen it make a difference.
It doesn't take long or cost anything more than some tape to try.
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Old Jul 22, 2014, 09:30 AM
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Australia, WA, Forrestfield
Joined Jan 2013
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Thanks for that link, I'll take a look. Thanks also for your hinge gap tip too (that's a mouthful) but there isn't a gap as such because I have used tape hinges - filament tape on underside and Bleniderm tape on topside.
Cheers
John
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Old Jul 22, 2014, 09:34 AM
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Australia, WA, Forrestfield
Joined Jan 2013
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Of course I meant I used a new h.stab not v.stab as mentioned in my first post
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Old Yesterday, 03:07 PM
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Joined Jan 2014
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along with the upgraded carbon props and spinner I would like to add these to my Radian Pro for easier set up. Can anyone confirm the length I would need for the fuselage and the wings...there's several length choices but I am not100% sure which I'd need. I could always do the unthinkable and actually measure it but I'm just curious if anyone knows. Thank you

http://www.espritmodel.com/servo-wir...connector.aspx
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Old Yesterday, 03:19 PM
Kool Kats Fly RC!! AMA 30462
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United States, CA, Baywood-Los Osos
Joined Feb 2009
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Originally Posted by brian0515 View Post
along with the upgraded carbon props and spinner I would like to add these to my Radian Pro for easier set up. Can anyone confirm the length I would need for the fuselage and the wings...there's several length choices but I am not100% sure which I'd need. I could always do the unthinkable and actually measure it but I'm just curious if anyone knows. Thank you

http://www.espritmodel.com/servo-wir...connector.aspx
I wasn't aware that Espirit had these pre-made, I made my own using the same Molex plugs. I made mine 6" long and wish I had made them a bit shorter, as it is still hard to stuff the excess wire into the small cavity provided in the fuse where the wings attach. Shorter is better, but despite mine being a bit too long it has reduced assembly time at the field by several minutes. Wise choice.

Sonny
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Old Yesterday, 03:26 PM
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Originally Posted by sonny1 View Post
I wasn't aware that Espirit had these pre-made, I made my own using the same Molex plugs. I made mine 6" long and wish I had made them a bit shorter, as it is still hard to stuff the excess wire into the small cavity provided in the fuse where the wings attach. Shorter is better, but despite mine being a bit too long it has reduced assembly time at the field by several minutes. Wise choice.

Sonny
I was looking online for some modification solutions to the wiring and came across someone that did the multiplex connectors themselves and linked to this website. When I did a search on the website I found those connectors themselves are out of stock but came across ones that were already pre wired. I'm all about not having to do anything extra if I can get it already pre soldered and ready to go.
also, what would be better the regular spinner or the turbo spinner the price difference between the two is not that much different
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Old Yesterday, 03:57 PM
Kool Kats Fly RC!! AMA 30462
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United States, CA, Baywood-Los Osos
Joined Feb 2009
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Quote:
Originally Posted by brian0515 View Post
I was looking online for some modification solutions to the wiring and came across someone that did the multiplex connectors themselves and linked to this website. When I did a search on the website I found those connectors themselves are out of stock but came across ones that were already pre wired. I'm all about not having to do anything extra if I can get it already pre soldered and ready to go.
also, what would be better the regular spinner or the turbo spinner the price difference between the two is not that much different
Well, there is some debate about the turbo spinners. I searched here on RCG a while back and found several conversations which indicated that some folks suspect that the turbo spinners create drag, even though they do provide some extra cooling. I decided to use the regular BB Aluminum spinner on my RP instead, but I do use turbo spinners on other planes, and haven't noticed any excess drag, (or much extra cooling for that matter). On this plane I don't think the extra cooling is especially necessary, (unless you are really pushing WOT for extended periods), so I would just use a regular spinner. However, I have found that the turbo spinners are much easier to attach/remove than regular spinners due to the way they attach to the motor shaft.
I found the connectors at Hobby King, there weren't any pre-made harnesses around that I could find at the time, so I just made my own harness. Like I said, it saves time at the field, and since I had made harnesses for other full-house sailplanes it wasn't really difficult.

Sonny
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Old Yesterday, 10:51 PM
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United States, NJ, Middletown
Joined May 2012
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So I bought two of the aeronut Turbo Spinners from esprit. The first one was defective as the choke became locked on the prop adapter about 1/4 inch up the shaft. I could not free it either way and will be calling esprit tomorrow to see what can be done. Worst case I will buy the bb alum spinner to replace it. The aluminum used in the aeronut products is way too soft. I'm glad I purchased two up-front though as the other went together without incident. Will be mounting it up tomorrow to test.

Anyone else have experience with the aeronut stuff?
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Old Yesterday, 11:09 PM
Kool Kats Fly RC!! AMA 30462
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United States, CA, Baywood-Los Osos
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Originally Posted by joshgluck View Post
So I bought two of the aeronut Turbo Spinners from esprit. The first one was defective as the choke became locked on the prop adapter about 1/4 inch up the shaft. I could not free it either way and will be calling esprit tomorrow to see what can be done. Worst case I will buy the bb alum spinner to replace it. The aluminum used in the aeronut products is way too soft. I'm glad I purchased two up-front though as the other went together without incident. Will be mounting it up tomorrow to test.

Anyone else have experience with the aeronut stuff?
I use one of these in 30mm, and haven't had any issues up to this point, and I use a regular BB Aluminum spinner, (not the turbo version), on my RP and haven't had a single issue with it either. I also have never noticed any deficiencies in the aluminum used in the BB spinners up to this point either. I'm sure Espirit will do the right thing, they've been around awhile, and you don't last long in this business by burning customers; they'll make it good.

Sonny.
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Old Yesterday, 11:09 PM
Drifting off the reservation..
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USA, LA, Broussard
Joined Jan 2011
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Quote:
Originally Posted by sonny1 View Post
Well, there is some debate about the turbo spinners. I searched here on RCG a while back and found several conversations which indicated that some folks suspect that the turbo spinners create drag, even though they do provide some extra cooling. I decided to use the regular BB Aluminum spinner on my RP instead, but I do use turbo spinners on other planes, and haven't noticed any excess drag, (or much extra cooling for that matter). On this plane I don't think the extra cooling is especially necessary, (unless you are really pushing WOT for extended periods), so I would just use a regular spinner. However, I have found that the turbo spinners are much easier to attach/remove than regular spinners due to the way they attach to the motor shaft.
I found the connectors at Hobby King, there weren't any pre-made harnesses around that I could find at the time, so I just made my own harness. Like I said, it saves time at the field, and since I had made harnesses for other full-house sailplanes it wasn't really difficult.

Sonny
I have the turbo spinner with the hole in front. I'm sure there is some drag but negligible in comparison to the draggy foam airframe. At thermaling speeds the drag does not mean much. It becomes noticable when trying to maintain airspeed for multiple loops (gliding). That pockmarked foam is quite draggy.

I have stick on plastic on the bottom of the wing which makes it slick as can be. I also have shiny stick on plastic (chrome) on the leading edge. The top of the wing becomes slightly "turbulated" with the rough foam, and IMHO that improves lift at thermaling speeds.

Drag is only an issue when running from sink and chasing thermals, but the spinner's contribution is negligible IMHO.
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Old Yesterday, 11:31 PM
Kool Kats Fly RC!! AMA 30462
sonny1's Avatar
United States, CA, Baywood-Los Osos
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Originally Posted by JumpySticks View Post
I have the turbo spinner with the hole in front. I'm sure there is some drag but negligible in comparison to the draggy foam airframe. At thermaling speeds the drag does not mean much. It becomes noticable when trying to maintain airspeed for multiple loops (gliding). That pockmarked foam is quite draggy.

I have stick on plastic on the bottom of the wing which makes it slick as can be. I also have shiny stick on plastic (chrome) on the leading edge. The top of the wing becomes slightly "turbulated" with the rough foam, and IMHO that improves lift at thermaling speeds.

Drag is only an issue when running from sink and chasing thermals, but the spinner's contribution is negligible IMHO.
Hi JS. I agree, I just wanted to put out that in some circles there is debate about turbo spinners, but I agree with you, drag isn't an issue with the RP. The old stick and tissue sailplanes we used to build had ribs with turbulators built into the design to slow the wing down, and I've wondered if adding some kind of turbulator to the smooth-topped RP wing might possibly improve it's characteristics. I have reflective mylar tape on the edges of my wing already, maybe I should run a strip all the way down the LE and see if I notice any difference.

Sonny
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