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Old Aug 29, 2009, 11:47 PM
Registered User
Canmore, Alberta
Joined Sep 2008
395 Posts
Thanks guys...I'll take the advice and increase the downthrust. Since my first fuse was destroyed it's hard starting from scratch but I'll hang in there. I still believe that this plane will be what I'm looking for as a stable AP ship.

Ram...I would love to know where you found those CAF stickers.

Regards,
Mark
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Old Aug 30, 2009, 02:00 AM
Registered User
United States, OH, Hamilton
Joined Nov 2003
1,187 Posts
[QUOTE=Rat]Patrick, leave the thrust angle alone as the Magpie alot of down right thrust to fly properly otherwise it will porpous (sp) baddly or try to climb steeply at anything over 1/4 power. The first one I built was not perfectly straight but with a couple minor adjustments with the trim it flew perfect for me.
QUOTE]

I think the Magpie has about 6* downthrust instead of the usual 2 or 3 degrees.
I think Doug said you could turn the mount to one side and tape in place for a little right thrust.

I thought the slit in the nose for the motor mount would spread and loosen so I made lite ply side braces and lined the slots with the slots in the foam.

http://www.rcgroups.com/forums/attac...hmentid=616314

David
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Old Aug 30, 2009, 02:44 AM
Registered User
United States, OH, Hamilton
Joined Nov 2003
1,187 Posts
To get right thrust, I held a side of the mount on top of the center piece and moved one end in the thickness of the ply and drew a line.

http://www.rcgroups.com/forums/attac...hmentid=616348

After sanding the grooves deeper, up to the line, it now has right thrust built in.

http://www.rcgroups.com/forums/attac...hmentid=616346

This made the mount more narrow but after sanding the fuse sides, it ended up being a perfect fit.

http://www.rcgroups.com/forums/attac...hmentid=616347

Doug also told me to angle the ailerons down just a little to help reduce climbing under power.
Line the ailerons up with the leading edge.

I was worried that it wouldn't get off the ground on it's maiden at 22oz. With the stock brushed "C" drive and 10x6DD it lifts off grass after about 5 or 6 feet with WOT and then throttle back. It climbs easily at 1/2 throttle or more. It cruises at 1/3 throttle and I always land dead stick. At 22oz it's still a floater.

David
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Old Aug 30, 2009, 11:23 AM
Registered User
Canmore, Alberta
Joined Sep 2008
395 Posts
I have rebuilding my Magpie nearly from scratch....using blue cor insulation for the fuse. I was wondering if I could ask someone to post a shot of their fuse. A picture directly from the side would really help me determine 2 things...amount of downthrust (although I will probably aim for about 6degree...thanks David) but most importantly...the angle of the horizontal stab as it relates to the fuse. I would be certainly grateful.

I was using an Eflite park 480 and I'm starting to wonder if it's just too much motor for this plane. Next time I maiden I'll keep it around 1/4 throttle.

Mark
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Old Aug 30, 2009, 01:17 PM
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wattsup_kz's Avatar
Kalamazoo, MI USA
Joined Aug 2003
2,892 Posts
Here are a few pics of one I have under construction.

Hope that helps.

Brian
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Old Aug 30, 2009, 03:50 PM
Registered User
United States, OH, Hamilton
Joined Nov 2003
1,187 Posts
Quote:
Originally Posted by mark_
I have rebuilding my Magpie nearly from scratch....using blue cor insulation for the fuse. I was wondering if I could ask someone to post a shot of their fuse. A picture directly from the side would really help me determine 2 things...amount of downthrust (although I will probably aim for about 6degree...thanks David) but most importantly...the angle of the horizontal stab as it relates to the fuse. I would be certainly grateful.

I was using an Eflite park 480 and I'm starting to wonder if it's just too much motor for this plane. Next time I maiden I'll keep it around 1/4 throttle.

Mark

Laying a straight edge flush on top of the horizontal fuse shows the horizontal stab is in line with the thrust line. This is at the prop, the motor would be mounted above the thrust line, tilting down at 6*

The wing incidence is pos 2*..or the stab is neg 2*, depending how you look at it. I think they measure the wing in relation to the thrust line so it would be pos 2* wing incidence...I think.

The 480 could be a big part of your pitching up under power.
You can see the the numbers for the EPS-350C-CS with a 10x6DD @ 9.6V (8 cell Kann 750mah) and it flys great.

http://www.gwsus.com/english/product...system/024.htm

No unlimited vertical of course but at 22oz, it's very stable and will easily loop from level flight and I get a good 8 minutes of easy flying and always land dead stick, I love floaters.

David
The 480 is almost triple the power
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Old Aug 30, 2009, 07:47 PM
Fly, crash... repair, repeat.
ramron67's Avatar
United States, NC, Chapel Hill
Joined Nov 2008
156 Posts
Quote:
Originally Posted by mark_
Ram...I would love to know where you found those CAF stickers.
Mark,

I am a Canadian expat. so decorating my planes with Canadian decals is my form of patriotism.

The decals are the Major Decals .40 size CAF. You should be able to find them just about anywhere.



Ram
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Old Aug 30, 2009, 07:49 PM
Registered User
Canmore, Alberta
Joined Sep 2008
395 Posts
David and Brian...thank you very much for the pictures and advice. It has helped me come to 2 conclusions :
1. The horizontal stab on my newly built fuse is not quite level with the line of thrust...this would cause some nose up.
2. My beloved 480 is way too much motor. I will continue to use but keep it at no more than 1/3 throttle when I re-maiden.

Regards,
Mark
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Old Sep 06, 2012, 03:31 PM
2 Mistakes Downwind
ToyBoy's Avatar
Portland, OR
Joined Nov 2004
414 Posts
6 years later

I'm currently packing to move for the third time since beginning this thread, and while I decide on the fate of my old Magpie (take it or sell/give it away?), I thought I'd post a follow up, just for fun.

Life got in the way and I've never advanced beyond beginner in this hobby. I didn't fly for several years, and forgot virtually all I'd learned. But before that happened, I did fly the Magpie quite a bit, mostly with a camera attached, and she received several modifications which you can see in the pictures.

Better landing gear, balsa-reinforced nose, a reinforced hole for the battery, servos moved forward, CF connecting rods, rebuilt motor mount, bigger motor, steerable tail wheel.

I was running an 11x7 prop (I'm not even sure what that means anymore, but it was certainly bigger than stock). This may have drawn too much current for the Pixie 20P because it would tend to cut out at full throttle. However, I never really needed full throttle.

The weight with the V-wing is about 590gm.

Now the question is, do I ship her all the way to Australia, or finally let her go...
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