HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Oct 26, 2012, 05:08 AM
Chess club geek with wings
blunight's Avatar
Brainerd, MN
Joined Aug 2008
1,047 Posts
Quote:
Originally Posted by geminiryan View Post
Nice Reaper! hey...whats that white stuff on the ground? its not time for that stuff yet!!
Thanks! Yea, the white stuff is a four letter word in my book - time to drag out the indoor planes.

Now if only Lee would come out with a small, slow wing built for indoor combat,
something around 16" with a stick mounted 24 gram motor, 8x4.3 GWS prop, 450mAh 2s battery
blunight is offline Find More Posts by blunight
Reply With Quote
Sign up now
to remove ads between posts
Old Oct 26, 2012, 07:49 AM
Will work for batteries..
sd2602's Avatar
USA, UT, Kaysville
Joined Feb 2005
462 Posts
What methods out there does everyone use to balance their reapers? I.e. balance it on their finger, use a balancing tool? Lee mentions using the wire method but I am not familiar with that. Thanks!
sd2602 is offline Find More Posts by sd2602
Last edited by sd2602; Oct 26, 2012 at 08:07 AM.
Reply With Quote
Old Oct 26, 2012, 07:55 AM
My dog ate my airplane
San Diego
Joined Dec 2008
181 Posts
Check out the Scythe, I built 1 light to fly slow with a 10 gram 3800 kV motor and 2s lipo, it is 5.5 oz and I could probably fly it at a large indoor venue, it turns on a dime. It's probably not as durable as a fully taped and laminated wing though, because I skipped a lot of that part to save weight.
sredlin is offline Find More Posts by sredlin
Reply With Quote
Old Oct 26, 2012, 08:12 AM
wheeeeee!
elCapitan's Avatar
United States, UT, Provo
Joined Oct 2011
905 Posts
The instructions used to (I haven't checked recently) include the most popular method, and that is to measure from the nose, back to the proper CG, then extend outward towards either side, and either make a mark with a pen, or put small push pins in. Then you can balance it on the pushpins while you arrange the electronics on the top, before you cut all the slots and actually install them.

In fact, I've started using the flat-headed push pins before laminating. Then you can just leave them there when you laminate, and you'll always have them as an easy reference.
elCapitan is offline Find More Posts by elCapitan
Reply With Quote
Old Oct 26, 2012, 10:09 AM
Chess club geek with wings
blunight's Avatar
Brainerd, MN
Joined Aug 2008
1,047 Posts
Quote:
Originally Posted by sredlin View Post
Check out the Scythe, I built 1 light to fly slow with a 10 gram 3800 kV motor and 2s lipo, it is 5.5 oz and I could probably fly it at a large indoor venue, it turns on a dime. It's probably not as durable as a fully taped and laminated wing though, because I skipped a lot of that part to save weight.
I'm building one now although it's going to be a speed demon with a 300 w rewound 2812 motor!!

I need something a little smaller for our gym. Leadfeather has the Firefly but I'd rather have one with an airfoil.
blunight is offline Find More Posts by blunight
Reply With Quote
Old Oct 26, 2012, 10:11 AM
Will work for batteries..
sd2602's Avatar
USA, UT, Kaysville
Joined Feb 2005
462 Posts
Quote:
Originally Posted by elCapitan View Post
The instructions used to (I haven't checked recently) include the most popular method, and that is to measure from the nose, back to the proper CG, then extend outward towards either side, and either make a mark with a pen, or put small push pins in. Then you can balance it on the pushpins while you arrange the electronics on the top, before you cut all the slots and actually install them.

In fact, I've started using the flat-headed push pins before laminating. Then you can just leave them there when you laminate, and you'll always have them as an easy reference.
The current instructions do not include anything on how to actually balance, just that it must be balanced and the CG is 10.5 inches back from the nose. What you described makes sense and sounds easy enough. I am thinking that to get the proper distance back on the wing tips the easiest way to do this would be to measure 10.5 inches back from the nose on the centerline of the wing (from front to back) and then use a square (or something with a 90 degree angle) and extend that line out? I hope that makes sense! Thanks for the reply!
sd2602 is offline Find More Posts by sd2602
Reply With Quote
Old Oct 26, 2012, 10:29 AM
Planes in flames,,,
jetpackninja's Avatar
Gravity Sucks
Joined Aug 2010
3,362 Posts
Yeah- That's how I do it.

I do similar to what Will does.
I find two sewing pins that have the round heads on them.
I put them on after the laminate and glue them in with a couple of dots of hot glue.
jetpackninja is offline Find More Posts by jetpackninja
Reply With Quote
Old Oct 26, 2012, 10:33 AM
Will work for batteries..
sd2602's Avatar
USA, UT, Kaysville
Joined Feb 2005
462 Posts
Quote:
Originally Posted by jetpackninja View Post
Yeah- That's how I do it.

I do similar to what Will does.
I find two sewing pins that have the round heads on them.
I put them on after the laminate and glue them in with a couple of dots of hot glue.
The instructions do mention that the wingtip fins must be attached. I am guessing that this still applies and the pins are inserted through them?
sd2602 is offline Find More Posts by sd2602
Reply With Quote
Old Oct 26, 2012, 10:40 AM
Planes in flames,,,
jetpackninja's Avatar
Gravity Sucks
Joined Aug 2010
3,362 Posts
?
The CG at 10.5 in back get you somewhere around the vacinity of the motor mount.
The pins are just pushed upwards into the foam on the bottom of the plane just giving you a reference point on where to balance the plane. they aren't gonna be anywhere close to the fins.
The reason that the instruction tell you to put the fins on is because of the sweep of the wing, the wingtips are behind the CG, so you will want to have them installed to get the cg right.
jetpackninja is offline Find More Posts by jetpackninja
Reply With Quote
Old Oct 26, 2012, 10:49 AM
Will work for batteries..
sd2602's Avatar
USA, UT, Kaysville
Joined Feb 2005
462 Posts
Quote:
Originally Posted by jetpackninja View Post
?
The CG at 10.5 in back get you somewhere around the vacinity of the motor mount.
The pins are just pushed upwards into the foam on the bottom of the plane just giving you a reference point on where to balance the plane. they aren't gonna be anywhere close to the fins.
The reason that the instruction tell you to put the fins on is because of the sweep of the wing, the wingtips are behind the CG, so you will want to have them installed to get the cg right.
Yep, i get that. What I am describing is inserting push pins into the wing tips. That way you can pick the wing up by them or set the wing between two items on the pins and then you can balance it that way.

Dreadlock, I hope you dont mind my using your pic!
sd2602 is offline Find More Posts by sd2602
Last edited by sd2602; Oct 26, 2012 at 10:55 AM. Reason: Added pic
Reply With Quote
Old Oct 26, 2012, 11:45 AM
wheeeeee!
elCapitan's Avatar
United States, UT, Provo
Joined Oct 2011
905 Posts
problem with that is that, as far as I can remember, CG is not that far back on any of the CTH wings. If you measured back form the nose to proper CG, then used a square to extend out to the sides, you'd extend onto the leading edge of the wing, not the tip.

So sticking a pin into the bottom of the foam is the way to go.

By the way, it's tough to get your square exactly straight along the center line of the wing, so a good way to double check is to make your marks near the edges of the wing, then measure along the leading edge from the nose, back to the mark you made. The measurement on the right and the left leading edge should be equal. ...make sense?
elCapitan is offline Find More Posts by elCapitan
Reply With Quote
Old Oct 26, 2012, 12:46 PM
Planes in flames,,,
jetpackninja's Avatar
Gravity Sucks
Joined Aug 2010
3,362 Posts
SD- are you building a deep reaper or a grim?
jetpackninja is offline Find More Posts by jetpackninja
Reply With Quote
Old Oct 26, 2012, 02:10 PM
Will work for batteries..
sd2602's Avatar
USA, UT, Kaysville
Joined Feb 2005
462 Posts
Quote:
Originally Posted by elCapitan View Post
problem with that is that, as far as I can remember, CG is not that far back on any of the CTH wings. If you measured back form the nose to proper CG, then used a square to extend out to the sides, you'd extend onto the leading edge of the wing, not the tip.

So sticking a pin into the bottom of the foam is the way to go.

By the way, it's tough to get your square exactly straight along the center line of the wing, so a good way to double check is to make your marks near the edges of the wing, then measure along the leading edge from the nose, back to the mark you made. The measurement on the right and the left leading edge should be equal. ...make sense?
Yeah, I think i get what you are saying. Measure 10.5 back from the nose where the CG should be. Then just pic an arbitrary distance to use and measure that from the nose down the leading edges of both the left and right side. Then measure from my 10.5 CG location to those spots on the leading edges. Those distances should be equal.

I think i understand the pin placement now. You guys are saying to have them at 10.5 (i am assuming at least 2 in a line) and then set the whole thing down and it should balance on those pins?

Sorry if I am making this way more confusing. If anyone has a pic that would be a huge help!

Ninja, I am building a grim.
sd2602 is offline Find More Posts by sd2602
Reply With Quote
Old Oct 26, 2012, 02:24 PM
Registered User
United States, CO, Denver
Joined Sep 2012
27 Posts
heres a screenshot of the instructions..

if you put your spar in accurately its either a half inch infront or half inch behind depending on configuration

in my photo above I have 2 spars on bottom, the top one is the one from the manual 10in back... as you see your arrows are no where near COG... my COG should be 1/2in above that spar, yours 1/2in below it since yours is a grimm.
dreadlocks is offline Find More Posts by dreadlocks
Last edited by dreadlocks; Oct 26, 2012 at 02:30 PM.
Reply With Quote
Old Oct 26, 2012, 02:31 PM
Will work for batteries..
sd2602's Avatar
USA, UT, Kaysville
Joined Feb 2005
462 Posts
Quote:
Originally Posted by dreadlocks View Post
heres a screenshot of the instructions..

if you put your spar in accurately its either a half inch infront or half inch behind depending on configuration

in my photo above I have 2 spars on bottom, the top one is the one from the manual 10in back... as you see your arrows are no where near COG... my COG should be 1/2in above that spar, yours 1/2in below it since yours is a grimm.
Thanks! However, i am building a grim reaper not a deep reaper. Sorry for the confusion. What I am looking for is a picture of how the pins were glued/attached at the 10.5 inches back from the nose. Thanks again!
sd2602 is offline Find More Posts by sd2602
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Sold Reaper GR60 Stagger_Wing Aircraft - Electric - Power Systems (FS/W) 0 Jan 13, 2010 01:43 AM
Sold Reaper GR 60 wrpsr1911 Aircraft - Electric - Power Systems (FS/W) 0 Jan 06, 2010 09:28 PM
Build Log House of Balsa "Grim Reaper" P51 Mustang Gun Jam Electric Warbirds 28 Dec 20, 2009 03:25 PM
Discussion Body count... Grim but it's really gotta be done. Bilbobaker Life, The Universe, and Politics 15 Nov 15, 2009 01:09 PM
Gallery Grim reaper Wickett R/C Pumpkin Contest 1 Oct 31, 2005 04:37 PM