a question about symmetrical wings

[woundedbear]

Hello everyone!
I am interested in building a symmetrical wing for a 400 series P-51 Mustang kit. Questions. #1. Is this possible? #2. Can it be done? #3. can it be done with the parts that come with a 400 series kit,(adding one extra B and C laser cut sheets, that would give you 2 complete sets of ribs) What I was thinking about doing is reshaping the 2 sets of wing ribs. If you take two F2 ribs for instance, and hold them side by side, overlapping the bottom edges so you have the blunt ends side by side so they are 1/4 inch on the blunt ends, you can see what a un-reshaped wing cross section would look like. Not so good. But if you reshaped the two F2 ribs...well it might work...I think... Somebody has to have tried this. It would look like a 500 series wing, that had extra ribs added to the underside...Darn if I only had a digital camera and know how to post pics ! I could make my point, without winding up with a long confusing story ! Darn I do hate being dyslexic !

[David Lewis]

Why do you want a symmetrical airfoil?

[Bill Gaylord]

Along with that, would it be for flying or display?

[woundedbear]

Hello Mr.Gaylord and Mr. Lewis
I want to build a 400 series P-51 with a symmetrical wing for several reasons. #1. The real P-51s had this type of wing. #2. I want to build it for static display, but maybe as an electric 4 channel RC, I'm not sure yet. #3. it would be a challenging build, a learning experience, and it would be an awful lot of fun. #4. If I could pull it off, as a flying model, of any kind it would...it would add greatly to my happiness, and sense of self worth. To be truthful, that sort of thing means more to a person who is disabled #5. Even if I can't build it to fly, maybe, I could make it into a super detailed model, using only wood...and as much as possible use only what came in the box.
Now if I could get some input from NcGunny, davidchoate, Bill Parker, and some of the other folks I have came to respect on this forum.
Being dyslexic means you have to try twice as hard to learn half as much.
Then there's the whole attachments thing, my computer has a camera, but how do I use it to put photographs on the forum? I am barely computer literate. I know that my HP touchsmart 15 can do a lot of things, but I was born BC, before computers, long before these things took over all of our lives. I am addicted to something I don't fully understand.
Wow! People who are dyslexic, bipolar, crippled, and old can surely ramble on.

[sandman]

Keep at it woundedbear I hope I can see your work someday. I know little about computers but I have good luck taking pictures with my camera that has an SD card and downloading that onto my computer. I then open up the picture with Paint so I can resize and crop them before I save them back down as a jpeg file. Keep em' flying!

[Bill Gaylord]

I would build the wing per plan, and then add wood to the bottom of the formers, sculpt to shape, cut new stringer notches, and then string the wing bottom with the new contour. It may also help to redesign the wing with a 1/8" wooden dowel rod LE, as the stock LE is a bit beefy for scale. I did this for an r/c conversion, which turned out to be my best flying Guillows warbird. The wing was constructed from hand cut formers with a better Phillips entry, which could be another option to cut your symmetrical formers by hand.

[davidchoate]

I believe it is Asymmetrical Airfoil. Allows lift inverted among other things I do not Yet understand. But it's probably less complex to understand than posting photos on here.Airfoils are getting closer on My list of things I set out to learn . I am still grappling with getting these things to Fly RC converted. Example Woundebear: I just bought a second Fairchild kit from Guillows, and a few Laser Cut sheets to build another wing for My Fw190. I ordered like 3 extra sheets of decals for each because thats how many attempts it generally takes Me to get it right, and I admit, Not RTF, but I have a few larger RC Planes that were LC kits, but they told me what motor,prop,battery, and servo placement and linkages were presented on the plans. Just to keep My sanity, and learn how to Fly. Bigger is easier, but I will never give up the challenge of getting these tiny Heavy Guillows kits to convert to RC, and Fly. I am also BC, and get headaches from computer screens, and can't type to save My own life. You are not alone My Friend.

[woundedbear]

First of all I would like the give a big thank you! To Bill Gaylord and davidchoate for your replies to this post, think you both for your time. I did a tracing of the F2 wing ribs from 1 of my 400 series p-51s. If you draw a straight line on a piece of paper and place two of the F2 ribs bottom to bottom,and trace around them. You can see that they do a symmetric wing," a very fat but symmetric wing", They don't even come close to make a Laminar flow airfoil. If you add a 1/4 inch extension to the center line in front of the blunt ends of the outline of the two F2 ribs. Then free hand the curvature to the ends of the two ribs to the 1/4 inch extension you still have a fat, but symmetric wing. Then if you measure from the tip of trailing edge to the outer edge of part E3 you get about 2 maybe 3 /16 of an inch to add to the center line, that gives you about 6 inches and 9/16. Then you try and find the center of that and the center of the F2 rib will be just in front of 4th notch from the front. And what does this prove...I have reached my thumb by going around my elbow! "But the question remains". How do you give a Guillow's 400 series P-51 Mustang a Laminar wing? You cut new wing ribs from C grain 1/16th inch soft balsa wood sheet.The have slightly blunt at the leading and trailing ends, they have slots that are 3/16 inches deep, into these slightly blunt ends that you have cut and you insert C grain strips that 1/4 inch wide and 1/16 inch thick. Oh! but first you drill holes into the widest part of each one of the 12 new ribs. These hole must be on a center line, at exactly 1/2 the distance from leading edge and trailing edge and 1/8 inch in diameter at the F12. and 3/16 to 1/4 at F1...too sleepy to go on

[woundedbear]

I would like to thank davidchoate, and Bill Gaylord for their advice. I have decided to build one of my 400 series P-51 kit's wings straight out of the box. This is something I should have done in the first place, but I did learn from the first build. I used push pins instead of tailor's pins, this is something I found on this forum, and it has made a big difference. I don't recall who's idea it was, but the other Guillow's kits I have built, so far, have been a big improvement over the first of the 400 series P-51 kit I build. My 300 series Piper Cub, and the two 500 series planes have perfectly straight fuselages. The first 400 series P-51's fuselage was as crooked as a dog's hind leg, but it wasn't a complete right off. Besides learning about using the push pins with wide shoulders that will hold down the parts along their edges, instead of tailor's pins, or T-pins that hold the parts by pearcing the wood. This not only does a better job of holding the parts in place, but if there is a wrinckle in the plans sheet the wide shouldered push pins will prevent the wrinckles from misaliging the parts, plus you don't poke alot of pin holes in the wood. After building the fuselage, and seeing the crookness of the center keel, I stared using the push pins. The vertical stabilizer, and the horizontal stabilizer assemblies came out perfectly straight. While sanding the leading, and trailing edges of the tail assemblies, I discovered that the CA glue was very hard, and that alot more wood was sanded away as a result, leaving the tail surfaces lumpy. I still use CA glue but sparingly, I've read that CA glue is very heavy compared to solvent based glues. I now use SIG Bond an aliphatic resin glue, I doubt it is mush lighter than CA glue, but it sands better, "without removing so much wood", and is said to be both Dope, and Fuel proof. Thined Ambroid I think would be the lightest glue to use, but the Ambroid company is no longer in business, so maybe I could find it on, "evil bay", for a ridiculous price, " I'll have to look into that". I do have one question, is there a tool that is designed to set the tail assemblies on the fuselage, and hold them inplace while the glue dries ? If there is such a tool where can one be purchased ? If such a tool or jig is available, can it be ajusted to set the angle of the Horizontal stabilized, and also set the vertical stabilizer at a such a degree that the trial, and error method would unnecessary. Such a jig would make setting up the tail of a free flight model airplane in such a way that flights would be much more perdictable, and if flying in a restricted field for instance, the tail could be dialled in to keep the model from going (OOS) Out Of Sight. This would be good for me, in that the field where I will be doing most of my flights, is relatively small, having a model plane trimed to fly in a smallish circles, would save my efforts from becomng tall tree causualties.

[davidchoate]

I have so many different adhesives. I have found that certain adhesives are necessary for different things. CA is strong, but ver hard, and if building a wheelpants from layered balsa CA would not be a good choice. I am always experimenting, and am currently testing fiberglass cloths, and resins as I am planning on larger builds soon. I have found Alphetic resins to be good on sandable needed areas, and some wood glues I have had come disadhered when I used it on things with a torsional force. Like wing spars. I use CA on them, but very carefully. I buy a bunch if tips that are like a needle thin long tube. They are good for only 1 or 2 uses, but cheap if You buy em by the Quantity.

[woundedbear]

davidchoate, Thanks for your reply about the glues and adhesives. Today has been an eventful one, first I received a call from an old friend that I have not had the chance to talk to since I dropped out of high school, back in 1975, that was fun. Here in Carolina where I live the weather has been very nice, and the wind was not gusting like it usually does. I live near the North Carolina Air Museum, close to Asheboro, and the Uwharrie Mountains. I have never lived in such a place the wind blows all of the time, often with gusty winds that make flying a free flight model airplane very interesting. Today I got out my foamy four channel Aircore P-51 Miss America. I had a 37-second flight, right into the ground nose first. While I was contemplating the damage, I received a small package that I had given up on ever getting. I had been on another forum,"sorry Guillows", anyway, I had contacted a gentleman in Texas. He did the design work for the De Havilland 103 Hornet for the now out of business Blue Bottle Squadron Company. He sent me the full-size build sheet for the airplane, of course, I will have to buy the laser cut balsa wood sheets,"I think there 12 sheets in all", and the vacuum formed parts, plus the hardware pieces. The airplane is in 1/16th scale and uses the box form type build for the fuselage, this was something that I had posted a question about on the Guillows forum and received some good advice from you and the other guys. I am planning on building it as per the instruction sheet, but the gears in my old noggin are ah turning. And thoughts of a twice as big," that would be a 67 and a half inch wingspan", an airplane with a six channel receiver, flaps, retractable landing gear, plus the usual throttle, rudder, elevator, and aileron controls. But I am getting ahead of myself, first there will be a three channel 400 series P-40, then perhaps a 1000 series P-47 or F6F Hellcat with a six channel receiver and flaps, plus retractable gear.

[David Lewis]

Ambroid, Duco or Testors acetone based model airplane glues used to be the most common. (They still make Duco.) Compared to aliphatic, though, they're not very strong. They're good for temporary joints. You can easily dissolve dried model airplane cement with acetone or dope thinner.

You can increase the strength of aliphatic glue by diluting it with water, or buy it pre-watered-down, such as Deluxe Materials SuperPhatic.

[davidchoate]

I wet the wood down before I apply it. It apparently really gets in the pores of the wood ("surface area!). But anyway I learned about it from the author of "The Masters Workshop". in Fly RC magazine. Bob Benjamin is His Name. It is the only really good Build column left in this RTF world. He did a Guillows RC conversion a while back, and a Dumas Pacer, and He shows You how to modify plans, and scratch build stuff. Like making cowls out of all wood and stuff. But woundedbear I think You may want to think about a high wing Trainer. I tried to learn on a couple Foam micro warbirds. I remember a BNF 18"WS Spitfire with 3axis and it was about a 20 second flight. Even with the auto stabilization. The bigger the easier to Fly. For Me anyway, and that SAFE technology is really what helped Me to gain confidence in Basic Piloting. I think now how they trained the WW2 pilots. Start in a Piper Cub, then a PT-17, and finally a T-6 before advancing to a Fighter. I don't think many Guys Just jumped in a Corsair and took to the skies. As much as I hate RTF's; They do serve as good Trainers.

[woundedbear]

Hello! davidchoate, As for bigger being better, I agree 100% As for the RTFs I'm thinking about starting a new thread. I think the fact that Flyzone's Aircore going away is just the tip of the iceberg, I think the days of getting cheap, "yet pretty good RC stuff", from out of China are going to come to an end soon, but it was good while it lasted. In a time of changes maybe it will turn out for the best. I think in the coming years we will see a lot of consumer goods being made here in the US. I can recall when George H. Bush was debating with Bill Clinton, and there was this little guy who was running as an independent, Ross Perot, he was saying things like,"if you boys go through with this free trade agreement, you a gonna hear a sucking sound, that's gonna be the sound of all of the jobs going out of this country", well he was right!, but this is a model airplane forum, "so I'm just saying". Good by to cheap consumer goods and hello more American jobs! Of course, Guillow's model kits have always been made in the USA. Of course, that brings up another Question I wonder how many folks does it take to run a company like Guillows? At first, you think to yourself," what may be 25, 30 people", then you think, "well there's bound to be more than that, Guillows puts out a lot of kits" And their wood has gotten so much better, plus they are converting to laser cut kits. Yep. I think Guillows is going to be around for a long time, and I for one am glad of it. To think when I'm too old to do all of the walking involved in flying free flight model airplanes, there will always be kids tossing Guillows stick and balsa sheet winged rubber band powered airplanes and dreaming of aviation. Shoot! What would a fourth if July week without seeing kids playing outside with their Guillows stick planes and gliders. When I think to myself this company's been around since the year my Mother was born, it's kind of comforting! I keep a couple of the "All most ready to fly" balsa wood airplanes around for when my nephew brings the grandkids to see their uncle Dave. Shoot. Sometimes when I'm out with those youngins flying the little airplanes with the red propellers I almost forget that I'm an old man now! All these years and it's still as fun as it was when I was a boy myself, and the reaction you see in the little kids when that little wooden plane with the red prop freewheeling gets caught up in an updraft and really floats in the air, it's WELL IT'S MAGICAL! Well, I've rambled enough for one night.

[davidchoate]

when I was like 4yrs old I guess around 1971. My Dad's Friend "Tony" used to bring Me a Guillows Stick red prop balsa sheet Wing Plane on Occasion. Needless to say He was like a God to Me. I sometimes will buy one for a kid like 4 yrs old hoping to ignite that spark of wonder at flight. And in all honesty;They Fly better than most of the kits! I have a Grandson about 9 or 10 now and last summer I gave him a Plane and I hope he wants to "Build" and not just Fly Planes. He is half Asian so He is very intelligent. He can Pilot better than Me.