jtec/radiowave
70cc twin V2
By the way, You're doing a hell of a build!!
Al
Al
Sport JTEC RADIOWAVE 26% Pitts Model 12
- Thread starter stangflyer
- Start date
stangflyer
I like 'em "BIG"!
Thank you... it's greatly appreciated. I totally get needing the break. Glad you had the opportunity to do so. I will gladly take time to give you my feedback on the road blocks I ran into. Granted, typically a builder "should" have at least an idea of how to proceed with certain building techniques, there also remains a certain degree of direction that one could use periodically to achieve the results that are intended. Unfortunately, (and not to my credit) I can be very "anal" and o.c.d.! . I fear I also get frustrated too easily. "Some" simple steps were overlooked in the manual. But not to the degree that it could not be handled. After this thing is done, I will relax and offer a few points that "may" assist others in this build endeavour.
With that being said, I made some progress on the lower wings. They are now sanded and ready to have the ailerons cut free, trailing edges for the wings glued in place, leading edges for the ailerons to be glued in place then beveled. I will also build the wing tips at the same time, then set them aside for covering. They turned out pretty darned sweet so far.
stangflyer
I like 'em "BIG"!
Well now I have gone and done it. I conjured up a recipe for scratching together some wing tips for the Pitts. Mmmm....tasty. LOL. Seriously, The weather here has been phenomenally perfect and I should have been flying. Can you all believe it? Sunny clear blue skies, High 60's and 2 mph winds gusting to 5. And I am building? I really need my head examined. Oh yeah, OCD Rob...Lets talk about those wing tips. I will fly tomorrow.
I really was not sure what I wanted or how to go about it. I knew I needed to make the wing tips strong but light. I had an idea from the photos I have looked at and @Bipeguy03 35 center Pitts. Ah ha...that should be fairly easy to duplicate. Ha, five hours later I have one half of one wing tip built. I figured a 3/32" sheet in the center of the wing tip rib would set my size and shape. Since the bays at the ends of the wings are roughly 3.5", I started with that and adjusted from there. My final width was 3" from wing tip rib to the end of the wing tip. I started with the lower bottom right wing first just in case I messed up, any mistakes would not be as easily noticeable as if it were on the top of the wing. Anyway, I drew out a patten of what I felt was pretty close to accurate, then traced that shape on to the sheet of balsa that will be the center of the wing tip. Drawing a straight line right through the middle of the wing tip rib would be the placement of the balsa sheet. I intentionally left that sheet just a smidgen short at the trailing edge of the aileron as the sheeting that will lay over the top and the bottom of the tip would need to have room to come together without leaving a "bulge".
I then drew out a curved flat rib for the "near" border of the balsa sheet from a piece of scrap 1/8" balsa sheeting. Using a 1/8" by 1/4" balsa strip, I then glued that to the exterior edge of the wing tip rib as a mounting stringer for the top sheeting.
Next I used 1/4" by 3/32" balsa strips to make the sheeting supports that will extend from the wing tip rib to the edges of the new wing tip. (I know, I know....Confusing huh?....wing tip rib for the wing tip?) I supported these with small extension pieces from the underside of the balsa stringer that runs the length from leading edge to trailing edge. Bringing them down to meet up with the flat rib that goes around the border of the new wing tip.
Once I had the ribs/supports in place... I lightly sanded a bevel in each one to allow the sheeting that will go on top of them the ability to lay flat when glued in place. Before doing so however, I decided to do a test fit of covering minus the sheeting. Just to see what it would look like. Had I designed the wing tip with the thought in mind of using covering only, it probably would have looked better. Ah well, off with the covering and on with the sheeting.
I made the wing tip skins from 1/16" balsa sheets. I really felt that using anything other than that would be a waste and add more weight than I wanted. Plus, it should be plenty strong enough. Once glue was applied to all the contact points for the skin, the sheets were placed into position then clamped down. Once again, those clothes pins came in pretty handy.
An ice cold Pepsi and a Canadian Bacon and Pineapple Pizza later, the glue was cured enough that I could remove the clothes pins to inspect the new wing tip. A little light sanding and very minor adjustments to the shape and lookie lookie. Not too shabby....
It is a little difficult to see the curvature of the wing tip at this point. But from what I could tell, it is pretty close to the way it is supposed to be. Once the other side is completed, I will do a final sanding then cut the aileron from the wing and finish up the hinge line. It won't be long and this wing will be 100% ready for covering. Now if I only had a definite decision for a scheme. LOL.
What do you all think? It is not too late to alter this wingtip. Any of you think I need to sand a little more "radius" on the wingtip? Also, with the added 3" to each wing tip, this will bring the overall wingspan to 78". What do you all think? An extra 6" wingspan make any difference in flight characteristics?
I really was not sure what I wanted or how to go about it. I knew I needed to make the wing tips strong but light. I had an idea from the photos I have looked at and @Bipeguy03 35 center Pitts. Ah ha...that should be fairly easy to duplicate. Ha, five hours later I have one half of one wing tip built. I figured a 3/32" sheet in the center of the wing tip rib would set my size and shape. Since the bays at the ends of the wings are roughly 3.5", I started with that and adjusted from there. My final width was 3" from wing tip rib to the end of the wing tip. I started with the lower bottom right wing first just in case I messed up, any mistakes would not be as easily noticeable as if it were on the top of the wing. Anyway, I drew out a patten of what I felt was pretty close to accurate, then traced that shape on to the sheet of balsa that will be the center of the wing tip. Drawing a straight line right through the middle of the wing tip rib would be the placement of the balsa sheet. I intentionally left that sheet just a smidgen short at the trailing edge of the aileron as the sheeting that will lay over the top and the bottom of the tip would need to have room to come together without leaving a "bulge".
I then drew out a curved flat rib for the "near" border of the balsa sheet from a piece of scrap 1/8" balsa sheeting. Using a 1/8" by 1/4" balsa strip, I then glued that to the exterior edge of the wing tip rib as a mounting stringer for the top sheeting.
Next I used 1/4" by 3/32" balsa strips to make the sheeting supports that will extend from the wing tip rib to the edges of the new wing tip. (I know, I know....Confusing huh?....wing tip rib for the wing tip?) I supported these with small extension pieces from the underside of the balsa stringer that runs the length from leading edge to trailing edge. Bringing them down to meet up with the flat rib that goes around the border of the new wing tip.
Once I had the ribs/supports in place... I lightly sanded a bevel in each one to allow the sheeting that will go on top of them the ability to lay flat when glued in place. Before doing so however, I decided to do a test fit of covering minus the sheeting. Just to see what it would look like. Had I designed the wing tip with the thought in mind of using covering only, it probably would have looked better. Ah well, off with the covering and on with the sheeting.
I made the wing tip skins from 1/16" balsa sheets. I really felt that using anything other than that would be a waste and add more weight than I wanted. Plus, it should be plenty strong enough. Once glue was applied to all the contact points for the skin, the sheets were placed into position then clamped down. Once again, those clothes pins came in pretty handy.
An ice cold Pepsi and a Canadian Bacon and Pineapple Pizza later, the glue was cured enough that I could remove the clothes pins to inspect the new wing tip. A little light sanding and very minor adjustments to the shape and lookie lookie. Not too shabby....
It is a little difficult to see the curvature of the wing tip at this point. But from what I could tell, it is pretty close to the way it is supposed to be. Once the other side is completed, I will do a final sanding then cut the aileron from the wing and finish up the hinge line. It won't be long and this wing will be 100% ready for covering. Now if I only had a definite decision for a scheme. LOL.
What do you all think? It is not too late to alter this wingtip. Any of you think I need to sand a little more "radius" on the wingtip? Also, with the added 3" to each wing tip, this will bring the overall wingspan to 78". What do you all think? An extra 6" wingspan make any difference in flight characteristics?
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stangflyer
I like 'em "BIG"!
Never thought I would have one myself. But I think I've fallen in love with this one. Lol
Snoopy1
640cc Uber Pimp
That just fantastic great job looks good like the way you did it. I b a set off wing tip for my stick 85 but it was difficult and very time consuming, like your way and effective. I built a foam plug then vacuum bagged the foam plug and then melted out the foam. it looks good but a lot of work.
Bipeguy03
150cc
Looks pretty good! The tips on my 35% have a little more radius at the leading edge but yours looks pretty close! As for how they will effect the way it flies, I don't think they will make any difference, they don't add any lift or drag to speak of they are just kind of good looking baggage 
I grabbed a picture of one of my 35% wing tips for ya.
I grabbed a picture of one of my 35% wing tips for ya.
stangflyer
I like 'em "BIG"!
Sweetness....thanks so much. I was hoping (and meant to ask if you would mind) you post a photo of the wing tip. I really appreciate it. I am going to go back and sand a little more radius before moving on to the next wingtip.Looks pretty good! The tips on my 35% have a little more radius at the leading edge but yours looks pretty close! As for how they will effect the way it flies, I don't think they will make any difference, they don't add any lift or drag to speak of they are just kind of good looking baggage
I grabbed a picture of one of my 35% wing tips for ya.
View attachment 91029
HRRC Flyer
GSN Sponsor Tier 1
Hey Rob, what's wrong with you? The weather was so nice here, even I took my Kaos out the field yesterday for couple of flights. . . . . 
I certainly have no business telling you or anyone else how to build anything, but since you asked I will offer my suggestion (albeit a little too late). I would have used a piece of plywood in the middle of the tip for some extra ding resistance. You could have cut out the middle to save weight or you could have left it on since I don't think your 3Dub would ever know the difference.
Build on Buddy, AFTER you go flying today. . . .
I certainly have no business telling you or anyone else how to build anything, but since you asked I will offer my suggestion (albeit a little too late). I would have used a piece of plywood in the middle of the tip for some extra ding resistance. You could have cut out the middle to save weight or you could have left it on since I don't think your 3Dub would ever know the difference.
Build on Buddy, AFTER you go flying today. . . .
stangflyer
I like 'em "BIG"!
Hey David, thanks for your suggestion. Truth be known, I actually considered using ply and then cutting "lightening" holes in it. Two reasons I chose the balsa over the ply is, one: when balsa structure comes together at a glue joint, it is nearly as strong as ply. I am usually quite anal how my planes are handled so I really didn't feel the strength would be an issue. I was more mindfull of watching the weight. Which was reason number two. Plus cutting the same holes to keep the weight off the wingtips, (which really wouldn't have been much) it would have been more work. Odd as it my seem, if I ever get a tiny ding in any of my airframes, it is usually the rudder. Bottom side. (Hmmm, imagine that!)Hey Rob, what's wrong with you? The weather was so nice here, even I took my Kaos out the field yesterday for couple of flights. . . . .
I certainly have no business telling you or anyone else how to build anything, but since you asked I will offer my suggestion (albeit a little too late). I would have used a piece of plywood in the middle of the tip for some extra ding resistance. You could have cut out the middle to save weight or you could have left it on since I don't think your 3Dub would ever know the difference.
Build on Buddy, AFTER you go flying today. . . .
Sunday evening: I think I have the radius I now am able to live with. I have now finished the lower right wing and also got the lower left wing completed to the same stage. I also sanded the trailing edge of the ailerons to a nice smooth edge to match the tail feathers. Besides the photo that @Bipeguy03 was kind enough to post as well as the photos from 2wings.com, the radius on the wings is just about as close as I dare sand in without damaging all the hard work. About all the is left is to cut the ailerons free and cap them and the trailing edge of the wings. The wingtips have been quite time consuming, but well worth it. I am very pleased with the outcome of the lower wings. Now lets see if the top wings come out as nice.
