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#1 chawkins Nov 21, 2012 03:54 PM

Top Flite Metrick
 
The Metrick is next on the building list and in doing some research on this I see alot of guys are saying to add dihedral to the wing to help it to turn better. I see in the instructions they say to (inboard panels) life one panel 1 1/8" with the other flat on the building board. If I am to incress the dihedral, howmuch?
I also plan to enlarge the rudder abit to help with turning.

Thanks in advanced for any thoughts on this and on building the Metrick :popcorn:

Chris

#2 monious Nov 21, 2012 09:38 PM

Plug the dimensions into Curtis's Sailplane Calc spreadsheet.
http://www.tailwindgliders.com/Files.html

I scaled up a TopFlight Wristocrat and inadvertently reinvented the Metrick. I shot for close to a 12 degree EDA and it flies very well.

-Chris (also)

#3 Brner Nov 27, 2012 12:50 PM

Subscribed: Just finished a Metrick for my wife to learn to fly with. Still have to balance it out and do some maiden test glides. Had an older kit that someone had started that I got off Ebay.

Good luck with your build Chris and will be interesting following along here.

Don

#4 Graham 65 Nov 29, 2012 04:58 AM

Learnt to build and fly with a Metrick in about 89, nice flyer and good looking.

Definitely needs more dihedral and the wood used for the trailing edge was way too soft resulting in many fixes. Didn't know better when I was building it. Use modern light gear and it will fly like a feather, servos, battery etc.

Went particulary well off the slope on light wind days.

Yellow and white colour scheme best.:)

Must dig it out and get it flying again. Will post pic if I can find it.

Enjoy the build.

#5 chawkins Nov 29, 2012 02:32 PM

Graham
Your right on the T.E. wood, to fragile for me, when I get to that point in the build I will look at different options. As for the dihedral I plan to go a little more than double from 1 1/8 to 2 3/4. I came to that as that is what a Sig Riser 2M is and I have always liked that way my Riser handled. I will also visit the fin and rudder. Thinking about elimanting the counter balance rudder to make the tail group look more akin to the Sagitta.

#6 lincoln Nov 29, 2012 06:30 PM

The Sagitta orignally had a balance rudder too. A bad idea, IMHO.

I just picked up a Metrick at an auction. I'll have to see how much dihedral it has. Was a bit of an impulse purchase, and it's been hidden away since then. I tend to only make impulse purchases when prices are too low, and in this case that was true.

#7 lincoln Nov 29, 2012 07:04 PM

2 Attachment(s)
Thought it might be appropriate to have a picture of a Metrick (green and white)in this thread. Note just how little dihedral it has compared to a Sagitta 600 (yellow, blue, and red). I suppose I need to figure out how to fix that. Hate to cut into such nice work. Winglets?? (Ugh!)

#8 lincoln Nov 29, 2012 07:23 PM

If you increase the dihedral the right amount, I don't think you need to add much at all to the fin and rudder. Very approximately, after measuring mine I get a Vv of .021. Allegro Lite has .024. Also, Allegro Lite moment is something like 26 inches or a tiny bit more, Metrick around 25 inches or so. That's pretty close. I suspect it will have significantly better damping than a Sagitta 600.
Quote:

Originally Posted by chawkins (Post 23328757)
The Metrick is next on the building list and in doing some research on this I see alot of guys are saying to add dihedral to the wing to help it to turn better. I see in the instructions they say to (inboard panels) life one panel 1 1/8" with the other flat on the building board. If I am to incress the dihedral, howmuch?
I also plan to enlarge the rudder abit to help with turning.

Thanks in advanced for any thoughts on this and on building the Metrick :popcorn:

Chris


#9 Brner Nov 30, 2012 05:32 PM

Another Green One....
 
2 Attachment(s)
It's actually a little darker green than the first picture shows, more like the second shot taken inside my shop, but here's my wife's Metrick. Waiting for some lead shot and have a couple more details to add.....

#10 rdeis Dec 03, 2012 10:22 AM

Mine's green and white, too! I picked up one with a failed wing at a swap meet years ago, haven't gotten around to repairing it yet.

#11 1stGeppetto Dec 05, 2012 04:36 AM

Metric
 
2 Attachment(s)
Here's a Metric that I finished earlier this year. The covering is Polyspan with Nitrate base, airbrush/faux with water base paints and a Butyrate clear coal. I nixed the dynamic compensating Rudder and replaced it with an enlarged standard one. Stock dihedral. I don't know the weight but It Fly's great!
Geppetto

#12 jolly01 Dec 05, 2012 06:00 AM

G,

You have skills!


Rich

Quote:

Originally Posted by 1stGeppetto (Post 23445682)
Here's a Metric that I finished earlier this year. The covering is Polyspan with Nitrate base, airbrush/faux with water base paints and a Butyrate clear coal. I nixed the dynamic compensating Rudder and replaced it with an enlarged standard one. Stock dihedral. I don't know the weight but It Fly's great!
Geppetto


#13 Brner Dec 05, 2012 11:58 AM

Quote:

Originally Posted by 1stGeppetto (Post 23445682)
Here's a Metric that I finished earlier this year. The covering is Polyspan with Nitrate base, airbrush/faux with water base paints and a Butyrate clear coal. I nixed the dynamic compensating Rudder and replaced it with an enlarged standard one. Stock dihedral. I don't know the weight but It Fly's great!
Geppetto

Very unusual paint scheme but also very nicely done. I like it....a lot. :)

If you could give us an AUW on your bird it would be greatly appreciated. The plan says 28-36 oz....I'd really like to take lessons from anyone that can build this to 28oz and still have it hold together in flight....lol

#14 kzimmerm Dec 05, 2012 12:57 PM

Quote:

Originally Posted by 1stGeppetto (Post 23445682)
Here's a Metric that I finished earlier this year. The covering is Polyspan with Nitrate base, airbrush/faux with water base paints and a Butyrate clear coal. I nixed the dynamic compensating Rudder and replaced it with an enlarged standard one. Stock dihedral. I don't know the weight but It Fly's great!
Geppetto

Geppetto is one of those rare breeds by virtue of his excellent modeling skills, really elevates this hobby to a very high level. He not only is an impeccable builder but his finishes are a piece of art.

Only few ever match the skills of Geppetto. He certainly makes a lot of modelers jealous.

Great work Geppetto! ;)

Kurt

#15 1stGeppetto Dec 07, 2012 11:35 AM

Kind words Gentlemen, thank you, I am humbled.

Geppetto


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