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Old Sep 26, 2007, 06:52 PM
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carbondale il
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Rave
My History on the Free Flight Forum

I have been looking for more information on the Ltd. Pennyplane and found the Banks plan but was unable to see it or download it, I don't know why not. During my search I reread some of the discussion on this forum when I first joined and had so many questions. I admitt I misunderstood where some of you guys were comming from. You spent so much time and effort trying to help me with free flight. I'm sorry and thank you. Kevin
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Old Sep 26, 2007, 07:47 PM
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Ajax, Ontario, Canada
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No apologies necessary, Kevin. You were absolutely new to modelling, had your own ideas on what you would like to do and there was initially some frustration on all sides .. but it's obviously all steadily working out for you. Happy to see it ... and keep up the good work!
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Old Sep 26, 2007, 08:41 PM
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carbondale il
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Thanks Applehoney. I have been wondering if you are well, I haven't seen a post from you for a while, I hope so. I think I have figured out how to make a plane with 300 square inches of wing area to compete in the Big E class. I want to build it maybe this winter.
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Old Sep 28, 2007, 11:47 AM
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Keremeos, BC Canada
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Hey, it's summer, and Applehoney has likely been working on his park-like back yard...

BTW, Jim, I just received another load of old plans, I'll see if there are any odd ones that you may be interested in.

Yeah, the first little while was kinda rocky, wasn't it, Kevin? You picked a pretty steep learning curve, and we are all glad for your success.
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Old Sep 28, 2007, 01:46 PM
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Nah.. .summer's over and I've decided to go for the 'natural look' back there. Actually I have another 120 tulip bulbs to put in, I really oughta move my butt and get on with it. Interested to see a plans listing, though ...
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Old Sep 28, 2007, 02:58 PM
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Applehoney, I think it's great that you like plants. My Step Dad took me to Shaw's Gardens in St. Louis soon after the marrage. It made a lasting impression on me. I live in an apartment so I just have a few house plants. I'd like to practice Bonsai sometime. The carbon fiber square tube came in so I'm working on the motor stick for a copy of a plane but with a different wing design. I'm going to make it with a flat center section and a dihedral at the center of both semispans in hopes the plane will land horizontally instead of nose diving when it runs out of power. I figured out a way to attach the stabilizer with rubber bands so if I have to make a new one I will be able to use the same motor stick, the same thing with the wing. I don't know yet which will work best - two loops or three loops of rubber. Two would give it more winds but I don't know if there will be enough power to keep the plane in the air untill the rubber winds completely out.
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Old Sep 28, 2007, 07:59 PM
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Ajax, Ontario, Canada
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>flat center section and a dihedral at the center of both semispans in hopes the plane will land horizontally instead of nose diving when it runs out of power.

Kevin, tip dihedral like that is a good layout for stability but it will make no difference to the model nosediving when power runs out. The latter will be due to either insufficient decalage ( difference in wing and tail incidences) or CG .. or a combination of both.

It sounds as though forward speed under power is providing enough 'lift' to keep it in the air ... but insufficient for a glide so it noses in. More wing incidence and/or a more rearward CG might be the answer(s)
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Old Sep 28, 2007, 09:49 PM
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Quote:
Originally Posted by Applehoney
It sounds as though forward speed under power is providing enough 'lift' to keep it in the air ... but insufficient for a glide so it noses in. More wing incidence and/or a more rearward CG might be the answer(s)
And enough downthrust to prevent stalling under power.
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Old Sep 29, 2007, 09:42 AM
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carbondale il
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Thanks guys, that gives me something to go on. It appears that even though it flys as it is and with no down thrust it will also fly with some adjustments. I'll just have to see. At present the CG is two thirds back from the wing's LE. With two loops instead of three maybe as the power runs out it will decend slowly to a soft landing. The wing's positive incidence is approximately 4 degrees and the stab's positive incidence is close to 1 degree. Once I build it I can change the incidence by adding shims, no major problem. At the gaps that will cause I can put tape over so then no drag. I can shim the thrust bearing for down thrust. It will have working elevators - small tabs. The carbon fiber tube is just big enough to put in a lightly sanded 1/4 in. square wooden core for reinforcement at both ends.
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Old Sep 29, 2007, 02:55 PM
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I have another question: If there is a wing with conventional dihedral and the balance point is determined then if that same wing is built with a flat center section and tip dihedral will the balance point be in the same place?
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Old Sep 29, 2007, 04:21 PM
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Ajax, Ontario, Canada
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Yes
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Old Sep 29, 2007, 05:34 PM
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Great! Thank you Applehoney, I'm good to go. I'll balance at the same place of the design that flew well but nosed dived at the end of power then re balance with a more aft CG by adding weight to the tail and add some down thrust. My problem was that I thought I had to move the wing forward to achieve a more aft CG. I definitely want to build with tip dihedral for the added stability. The Big E I'm thinking about building would be the same design but bigger. I'm thinking about tissue covering only on top of the wing and stab for it. The ribs will be made with the airfoil needed but with the curve only - 1/16 or 1/8 x 1/4 in., no flat bottom for the ribs. For as long as the motor stick will be : 39 in. and 38 in. of 1 loop of 1/4 in. rubber, the propeller should turn for a long time. I want to learn how to use a winder, then I can put 57 in. of rubber on it ( I think ). A 10 minute flight is the goal. I believe I found something I can compete with. My Legal Eagle won't fit on the plan page anymore. I'm hoping for a 100 yard flight or more with it.
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Old Sep 29, 2007, 07:45 PM
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>My problem was that I thought I had to move the wing forward to achieve a more aft CG.

If possible, moving the wing forward is better than adding weight at the rear. Incidentally, rig your stab at zero incidence and drop the wing to three degrees (if necessary)
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Old Sep 29, 2007, 08:08 PM
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Sounds good Applehoney. Thanks again.
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Old Oct 08, 2007, 02:42 PM
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carbondale il
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I've got the motor stick done for the extra large " Ltd. Pennyplane" The rear motor hook is a large prop shaft through a hole in the carbon fiber square tube I'm using. I bent it 90 degrees on the top side and Gorilla glued it to the tube and then wrapped it with super strong thread then coated it with Elmer's glue. At the exit hole on the bottom I put Gorilla glue. At both ends only I inserted a wooden core - bass wood at the rear where the motor hook is and balsa at the nose. For the prop hanger I used a 1/2 in. wide 90 degree bracket with screw holes - one hole on each side. I widened the motor stick with bass wood at the nose and Gorilla glued the bracket on. Then wound it with the thread and sealed it with Elmer's glue. The bracket hole is almost big enough to accept the thrust bearing so I filed down the bearing shaft. I had a slot cut from one side of the bracket prop hanger hole through to the hole so I can slide in the prop assembly and remove it easyly. The rubber - two loops of 1/4 in. broke at 1000 winds. Everything works. The 11 in. plastic prop unwound smoothly ( after balancing ) with a test at 400 winds. For down thrust I made a balsa wedge to fit around the thrust bearing shaft and coated it with several layers of Elmer's. I glued it to the thrust bearing with super glue ( CA? ) so it will stay put and I'm using a small rubber band to keep it from turning to one side.

The not so Legal Eagle is done - it's a strange looking plane. Kevin
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