42% Super Decathlon Build
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RE: 42% Super Decathlon Build
Jack, when you are writing a reply look at the lower center of the text box and click on "Click here to upload images and files!". When the "Select a file to upload" box appears click on "Browse". Now double click "Computer", double click "OS(C):, double click on folder where your photos reside, double click on photo then click "OK" to upload photo. Takes longer to tell how to do it than it does to do it.
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RE: 42% Super Decathlon Build
Finally making some progress on the wings. The strut bracket issue is resolved, thanks to help from Ken and David. I reversed the main strut brackets which gave me a half inch below the wing surface. This required filling the holes in W31, W36, W35 and W15 with dowels and redrilling. Jack mada a simple jig to insure equal spacing. I've included some pictures to illustrate this. Picture 1 shows W31 with W36 glued to it (but not glued to the wing yet), picture 2 shows the jig in place. I then glued the brackets to the wood, using gorilla glue and clamped them (picture 3). After the glue had dried, I removed the part, and redrilled, using a drill press. I then glued the assembly to the wing and attached the bolts.
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RE: 42% Super Decathlon Build
We were in Bud's garage this morning, working on the 42% SD and I took a few photos I'd like to share. Photo 1 intorduces Jack (blue shirt) and Bud, the retired owner of arguably one of the finest hobby shops in the Midwest (if not the world)and the fuselage of the SD. Photo 2 shows the two 52 oz. tanks, one for fuel and one for smoke. Photo 3 is the DA 170 and Jack's very nice work on the engine mount. Photo 4 shows one of the two 2.4 receivers and the antenna separation (red tubes). We'll be using an Airtronics SD10G radio. Photo 5 is the wiring diagram for the two receivers. Photo 6 is the rudder pull-pull system and the bay for the second receiver. Photo 7 is the very nice panel and photo 8 shows the great garage, full of airplanes. We are having a ball with this kit and hope to have it finished by September. Might be a big hope but we'll sure try.
Frank
Frank
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RE: 42% Super Decathlon Build
A true work of art, almost a pity to cover it later...
Keep the pix coming, guys...thinking of doubling my 30% scale...
Marcus
Keep the pix coming, guys...thinking of doubling my 30% scale...
Marcus
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RE: 42% Super Decathlon Build
Michel,
a little off topic...
a friend of mine (who also bought one of my Decathlons) ordered one of your 50% Spacewalkers, and commited me to build it. Will write a full report and post pix here on RCU, what do yo think?
Marcus
a little off topic...
a friend of mine (who also bought one of my Decathlons) ordered one of your 50% Spacewalkers, and commited me to build it. Will write a full report and post pix here on RCU, what do yo think?
Marcus
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RE: 42% Super Decathlon Build
Thanks, Marcus, kind words from a guy who puts out such beautiful work as you do. We'll keep the pictures coming.
Michel, we've enjoyed the kit very much. When we've run into anything out of the ordinary, we've either figured it out or received help from guys like Ken, Marcus and David. This thread has been a big, big help. Looking forward to seeing the 50% Spacewalker.
Frank
Michel, we've enjoyed the kit very much. When we've run into anything out of the ordinary, we've either figured it out or received help from guys like Ken, Marcus and David. This thread has been a big, big help. Looking forward to seeing the 50% Spacewalker.
Frank
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RE: 42% Super Decathlon Build
Hey Frank
I´m flattered by your words. And yes, I happen to have fallen in love with Decathlons and love them in any size. But I really get upset when I see how many lookalikes are on the market out there, really few have true scale (or very close) outlines, especially on the nose area. I have addressed that a couple of times in other Decathlon threads, if the Cowl isn´t right, no matter how correct and well built the rest of the airplane is, it will look wrong. And the opposite is true as wel, if the cowl DOES look right, no matter how "wrong" the other areas of the plane are, it will look like a Decathlon.
That´s why I am happy to have been able to help Michel and Vincent a little when developing the mold for the cowl of this 42% beauty a couple of years ago. Nevertheless, I oversaw one little flaw which I don´t know if it has yet been corrected - however, Ken did the correction on his model: There should be NO protuberant spinner ring - the full size cowl is flush with the rest - and the splitting cut on the spinner ring must be slanted upwards to allow for reaching the prop hub hole, just as on the full scale. If necessary, ask Ken to post the pix again...
Sorry, maybe I am rushing ahead - but this is really important for the overall look, IMHO...
I am working on the last of the Mohawks - the last built up SD on my stock...this time in yellow. Will post pix later, just to get the juices flowing.
Nuff said, have a nice Sunday
Marcus
I´m flattered by your words. And yes, I happen to have fallen in love with Decathlons and love them in any size. But I really get upset when I see how many lookalikes are on the market out there, really few have true scale (or very close) outlines, especially on the nose area. I have addressed that a couple of times in other Decathlon threads, if the Cowl isn´t right, no matter how correct and well built the rest of the airplane is, it will look wrong. And the opposite is true as wel, if the cowl DOES look right, no matter how "wrong" the other areas of the plane are, it will look like a Decathlon.
That´s why I am happy to have been able to help Michel and Vincent a little when developing the mold for the cowl of this 42% beauty a couple of years ago. Nevertheless, I oversaw one little flaw which I don´t know if it has yet been corrected - however, Ken did the correction on his model: There should be NO protuberant spinner ring - the full size cowl is flush with the rest - and the splitting cut on the spinner ring must be slanted upwards to allow for reaching the prop hub hole, just as on the full scale. If necessary, ask Ken to post the pix again...
Sorry, maybe I am rushing ahead - but this is really important for the overall look, IMHO...
I am working on the last of the Mohawks - the last built up SD on my stock...this time in yellow. Will post pix later, just to get the juices flowing.
Nuff said, have a nice Sunday
Marcus
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RE: 42% Super Decathlon Build
Although it´s not 42% scale, here a few pix of the last SD I am finishing at this moment, base on the full-size of the first picture. I made one concession, though - I finished the underside of the wing with the well known invasion stripes which makes it easier to distinguish the plane against the blue sky.
Finishing is going far quicker than usual as I am using Oracover instead of Oratex, so I don´t have to clearcoat the entire airplane, and also the sunray design is far easier to do than the deluxe starburst.
All trim done in Orastick. Although some of the pix show a darker yellow, it´s a lighting problem. I am using Cadmium Yellow Oracover, which is about the same as on the fullsize picture. As soon as I take some outdoor pictures, the color match will be much more noticeable. Same for the cowl paint (not yet clearcoated/fuelproofed)
Enjoy...
Marcus
Finishing is going far quicker than usual as I am using Oracover instead of Oratex, so I don´t have to clearcoat the entire airplane, and also the sunray design is far easier to do than the deluxe starburst.
All trim done in Orastick. Although some of the pix show a darker yellow, it´s a lighting problem. I am using Cadmium Yellow Oracover, which is about the same as on the fullsize picture. As soon as I take some outdoor pictures, the color match will be much more noticeable. Same for the cowl paint (not yet clearcoated/fuelproofed)
Enjoy...
Marcus
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RE: 42% Super Decathlon Build
Fellows,
here a few additional pix - most of trims done, all that´s missing is the sunray pattern on the tail and the N numbers.
Taking the cowl and pants to the painter today to be clearcoated. And yes, the wheelpants trim has no white outline!
Enjoy
Marcus
here a few additional pix - most of trims done, all that´s missing is the sunray pattern on the tail and the N numbers.
Taking the cowl and pants to the painter today to be clearcoated. And yes, the wheelpants trim has no white outline!
Enjoy
Marcus
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RE: 42% Super Decathlon Build
At what point onthe vertical fin does the flair or fillet start? All of the pictures we have do not have enough detail to determine where the sides of the vertical fin cease to be vertical and begin to flare to the fuselage side. Thanks
Jack
Jack
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RE: 42% Super Decathlon Build
Jack
to understand this, one must be aware of the way the fullsize was built. Actually, it´s a triangular truss welded tube structure, over which 1/2" plywood formers are placed and over these, wooden longerons.
Let´s take a look at the 4 top longerons. The outer 2, which define the fuselage width, end at the rudder post. The inner 2, "die" earlier, right in front of the stab attachment. There is no such thing like a fillet, only a curved tube soldered to the rudder and the top (non-aparent)middle tube. The fabric covering, when shrunk and tautened, makes for that undefineable compound curve that can only be replicated if done exactly the same way. I am including 2 pictures of Aeronca 7AC Fuselages, which are basically the same for Citabrias and Decathlons, as shown by the 2 smaller pictures taken at the ACA factory.
It is important to keep in mind that the full-size is covered in 2 pieces of fabric, reaching all the way from the middle of the bottom to the midle of the top, and the fin is integral with these side pieces, and the fabric is stitched to the fin diagonal braces. As the lowest diagonal brace on the fullsize is about 40% of the fin height, that´s the point where actually the flare begins. The halves are stitched together at the middle, both top and bottom, and covered with tape. Dope, primer and paint make for an almost invisible joint line. This is hard to do on a model but it is possible. I was able to replicate it with reasonably good results by covering the bottom and sides separately, and then the top in 2 halves with integral fin, joining in the middle. IMPORTANT: these sections were not ironed on, but CA´d onto the edges and the middle joint as well. Otherwise, when stretching with the heat gun it would come off the edges (which doesn´t happen on the full-size because the fabric is one single piece each side...)
The correct stab outline (top view) will show a non-parallel gap, i.e., the inboard edges of the stabs will be slanted forward, to accomodate fabric shape and keeping a parallel gap between the stab and the fin.
Most kit makers (including myself) make concessions in that area in order to ease the building process. In most kits, there is a 60-size-trainer-style butt attachment of the rudder fin over a flat top surface (in some cases with a small balsa or plastic fillet) and a direct attachment of the stab halves to the flat fin sides.
I do it a bit different. I also do sheet the section between the 2 inner longerons way down to the end of them, under the fin. I keep the parallel stab-fin gap (3mm) which looks scale, and 2mm in front of the front stab attachment tube I glue a small triangle of balsa for the covering to attach to allow for the fabric (or plastic film) to make that compound curve (can be seen on pix 5 and 10). It is not actually necessary for the curve itself, but to create an edge where I glue the covering onto, otherwise when shrinking the fabric it will again come off the edge and enlarge the hole for the stab tube way too much. When covering the fin, I make a small cut under the front hole to allow for the in-between-stab-tubes-section to be ironed onto the flat fin surface while the front part conforms to the fuse/fin transition and form that beautiful curve.
Maybe hard to understand as a text but I am including some photos to show how it´s done.
Any further questions, please don´t hesitate to ask...hope this has been of help.
Marcus
to understand this, one must be aware of the way the fullsize was built. Actually, it´s a triangular truss welded tube structure, over which 1/2" plywood formers are placed and over these, wooden longerons.
Let´s take a look at the 4 top longerons. The outer 2, which define the fuselage width, end at the rudder post. The inner 2, "die" earlier, right in front of the stab attachment. There is no such thing like a fillet, only a curved tube soldered to the rudder and the top (non-aparent)middle tube. The fabric covering, when shrunk and tautened, makes for that undefineable compound curve that can only be replicated if done exactly the same way. I am including 2 pictures of Aeronca 7AC Fuselages, which are basically the same for Citabrias and Decathlons, as shown by the 2 smaller pictures taken at the ACA factory.
It is important to keep in mind that the full-size is covered in 2 pieces of fabric, reaching all the way from the middle of the bottom to the midle of the top, and the fin is integral with these side pieces, and the fabric is stitched to the fin diagonal braces. As the lowest diagonal brace on the fullsize is about 40% of the fin height, that´s the point where actually the flare begins. The halves are stitched together at the middle, both top and bottom, and covered with tape. Dope, primer and paint make for an almost invisible joint line. This is hard to do on a model but it is possible. I was able to replicate it with reasonably good results by covering the bottom and sides separately, and then the top in 2 halves with integral fin, joining in the middle. IMPORTANT: these sections were not ironed on, but CA´d onto the edges and the middle joint as well. Otherwise, when stretching with the heat gun it would come off the edges (which doesn´t happen on the full-size because the fabric is one single piece each side...)
The correct stab outline (top view) will show a non-parallel gap, i.e., the inboard edges of the stabs will be slanted forward, to accomodate fabric shape and keeping a parallel gap between the stab and the fin.
Most kit makers (including myself) make concessions in that area in order to ease the building process. In most kits, there is a 60-size-trainer-style butt attachment of the rudder fin over a flat top surface (in some cases with a small balsa or plastic fillet) and a direct attachment of the stab halves to the flat fin sides.
I do it a bit different. I also do sheet the section between the 2 inner longerons way down to the end of them, under the fin. I keep the parallel stab-fin gap (3mm) which looks scale, and 2mm in front of the front stab attachment tube I glue a small triangle of balsa for the covering to attach to allow for the fabric (or plastic film) to make that compound curve (can be seen on pix 5 and 10). It is not actually necessary for the curve itself, but to create an edge where I glue the covering onto, otherwise when shrinking the fabric it will again come off the edge and enlarge the hole for the stab tube way too much. When covering the fin, I make a small cut under the front hole to allow for the in-between-stab-tubes-section to be ironed onto the flat fin surface while the front part conforms to the fuse/fin transition and form that beautiful curve.
Maybe hard to understand as a text but I am including some photos to show how it´s done.
Any further questions, please don´t hesitate to ask...hope this has been of help.
Marcus
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RE: 42% Super Decathlon Build
Eventually the yellow SD is ready, done, finito...last one in the series of ARF´s. This one all done in Oracover instead of Oratex, and no clearcoating/fuelproofing except for the glass parts. Estimated weight 15% lighter than the previous versions.
I only didn´t do the N# because I left that open for the customer to choose.
Now I am thinking of doing a building pause - building Decathlons, that is - except for assemblying kits.
I already commited to build another airplane for a fellow customer - a Balsa USA 1/3 scale Ercoupe with all bells and whistles. The box(es) will be arriving this week. Next in line is a 50% AMR Spacewalker for the same guy.
See ya fellas around, will also post pictures of my SD kitbuilders´ projects.
Marcus
I only didn´t do the N# because I left that open for the customer to choose.
Now I am thinking of doing a building pause - building Decathlons, that is - except for assemblying kits.
I already commited to build another airplane for a fellow customer - a Balsa USA 1/3 scale Ercoupe with all bells and whistles. The box(es) will be arriving this week. Next in line is a 50% AMR Spacewalker for the same guy.
See ya fellas around, will also post pictures of my SD kitbuilders´ projects.
Marcus