Better wing for the FT Viggen

[aerojunkie]

Drawback of the KFm2 wing is it creates lift while upright and has the opposite effect inverted. Makes it a lot harder to take polaroids while inverted in a negative 4g dive with a mig 28

Nothing makes we want to fly like watching that movie

 

[Rasterize]

...but the plane is back in @Rasterize 's hands and i know he removed them when he stripped the plane.

I think you removed the landing gear before getting it back to me. From what I remember you had the typical FT wire configuration mounted to an external flat piece of wood.

 

[TheBigPancake]

Set the printer setup to full size and then select Poster print. On the poster print setting page you can select a few further options including cut marks and the like!

You need a relatively recent version of acrobat reader as those functions are not available on earlier versions!

Have fun!

Thank you

 

[TheBigPancake]

Are there any print out planes for this new wing? I am having a similar problem with my viggen. the wings folded almost completely in and caused some bizarre flight characteristics. Luckily I was able to bring her back home, but it was a challenge. Thoughts on adding some spars that are flush with the angle on the fuselage made out of simple bbq skewers?

 

[BATTLEAXE]

@Hai-Lee made a similar mod you are asking about. He will tell you how it's done. Just fire up the bat signal

 

[Hai-Lee]

Are there any print out planes for this new wing? I am having a similar problem with my viggen. the wings folded almost completely in and caused some bizarre flight characteristics. Luckily I was able to bring her back home, but it was a challenge. Thoughts on adding some spars that are flush with the angle on the fuselage made out of simple bbq skewers?

I have built a few Viggens of late and so far none have had wing sag or fold problems. The first Viggen I saw in flight was a genuine FT kit using the FTFB and it was somewhat flexible from the start. (The owner had flown it without any sealing or the like and it was flexible in the wings from the get go! He eventually went the KFM route and whilst the wing was stronger the performance was effected negatively.

With my latest builds I actually use a length of CF tube the same diameter as the FB is thick. The single CF tube length, (1 metre), is cut into two pieces and The two pieces are fitted into the FB by cutting channels for the CF in the wing UPPER surface firstly around 1.5 inches in front of the elevon hinge line and The smaller piece is fitted in another channel cut in the wing upper surface around 3 inches from the most forward part of the wing, (the exact positions are not that important but do not have the CF reach to the wing edge as it reduces the resilience and ability to repair in the case of a crash. I use epoxy to fit the CF into the FB channels. Try to keep it neat and wipe off any excess from the epoxy before it sets.

Once the CF tubes are fitted and the glue is set, seal the exposed FB wing edges with glue and then minwax and seal the wing. Paint the heck out of it!! The paint actually makes the FB more rigid but only if the FB is properly sealed first. The wing should/will fit onto the fuselage exactly the same as before prior to sealing and painting of course.

If you crash the wing edges will be damaged but you can cut out severely damaged pieces and graft in patches which you seal and paint to match. So far I have not seen one with CF reinforcing actually crash beyond repair even though there have been treeings, and total OOC landings.

All of this does add a bit of weight but with the larger motor or EDF setup the bird still performs very well!

I hope my experience helps you getting your bird back in the air!

have fun!

 

[TheBigPancake]

I have built a few Viggens of late and so far none have had wing sag or fold problems. The first Viggen I saw in flight was a genuine FT kit using the FTFB and it was somewhat flexible from the start. (The owner had flown it without any sealing or the like and it was flexible in the wings from the get go! He eventually went the KFM route and whilst the wing was stronger the performance was effected negatively.

With my latest builds I actually use a length of CF tube the same diameter as the FB is thick. The single CF tube length, (1 metre), is cut into two pieces and The two pieces are fitted into the FB by cutting channels for the CF in the wing UPPER surface firstly around 1.5 inches in front of the elevon hinge line and The smaller piece is fitted in another channel cut in the wing upper surface around 3 inches from the most forward part of the wing, (the exact positions are not that important but do not have the CF reach to the wing edge as it reduces the resilience and ability to repair in the case of a crash. I use epoxy to fit the CF into the FB channels. Try to keep it neat and wipe off any excess from the epoxy before it sets.

Once the CF tubes are fitted and the glue is set, seal the exposed FB wing edges with glue and then minwax and seal the wing. Paint the heck out of it!! The paint actually makes the FB more rigid but only if the FB is properly sealed first. The wing should/will fit onto the fuselage exactly the same as before prior to sealing and painting of course.

If you crash the wing edges will be damaged but you can cut out severely damaged pieces and graft in patches which you seal and paint to match. So far I have not seen one with CF reinforcing actually crash beyond repair even though there have been treeings, and total OOC landings.

All of this does add a bit of weight but with the larger motor or EDF setup the bird still performs very well!

I hope my experience helps you getting your bird back in the air!

have fun!

Thank you for the response! I will experiment with the different techniques you have mentioned. I love my viggen and wanna get it back in the air!

its a speedbuild kit, however i have tons of DTFB to experiment with and try new things Appreciate your help!

 

[Hai-Lee]

Thank you for the response! I will experiment with the different techniques you have mentioned. I love my viggen and wanna get it back in the air!

its a speedbuild kit, however i have tons of DTFB to experiment with and try new things Appreciate your help!

Here are a few pics of the CF spars added/fitted in one of my recent builds just to give you the idea.







Have fun!

 

[JDill]

Sorry for not checking back in for a while on this thread I started, doh!

To answer a couple questions...
The Viggen flies great with the re-designed wing. I have had many flights on it since the change. It's one of my go-to planes to take to the field. I love how with the Viggen you can basically drop the tail and park it into the wind, and do the same to drop it right in front of yourself for a landing.

I do not have plans for the re-design, but between my description in the first post and the photos you'll get a good idea of how to do it using the original wing template.

By the way, I have also cut away the original vertical stabilizer and made a new one with two layers of foam-board for strength and straightness.