Discussion A case for bagged wings

[harleym]

It was just called to my attention today that a thread was started back in August about the viability of bagged wings in today's modeling environment. The link to that discussion is http://www.rcgroups.com/forums/showthread.php?t=1099766. I read the various responses and found them to make worthwhile reading.

I've been kicking around longer than most who read this forum so have some perspective not offered in the responses.

I got interested in models in the depths of the Big Depression. With my dad making as little as $50 a month when employed full time there simply was no money for frivolity. If you wanted something resembling a model it involved innovation, scrounging for raw materials and building from scratch. In high school in the late 1930's, I could buy a few materials, but to keep costs down, continued to scratch build my own designs. Having learned that art, I've stuck with it for life. Money has long not been an issue. The motivation is the gratification experienced by doing original, creative work.

I did sticks, sheets, ribs and film until discovering foam cores to sheet over. When Frank Weston came up with cloth skinned foam core wings, I learned that and have been making bagged wings for myself with techniques personally developed over the last 17 years.

With the advent of the moldie, I had one a short time but quickly determined my own bagged wing stuff handled and performed as well.

In the above mentioned link, the question was put why bagged wings may have lost their popularity. My take is that what has lost its popularity is doing something for yourself, and instead just laying out easy money to buy the ARF, while letting building skills go undeveloped or atrophy.

In addition there is the mindset that only the moldie can be competitive. Of course, it is what is most competitive because it is what the bulk of the modeling fraternity of skilled and competitive fliers is using.

Had the ARF not appeared, can you imagine what fine airframes would otherwise have been designed by resourceful and innovative modelers having put their minds to the task? I'll bet they would employ vacuum-bagged wings which can be scratch built to look very nice, and with precision cores available such as Anker can provide, will yield fine performance and also handle the high stress launches we like to do.

An attitude adjustment is called for. What we fly need not be only the costly moldie or some limited performance woodie. Scratch built, bagged wing ships work just great. I know. . .I've built 2-3 a year for 17 years. Others who have built them are full of praise, too.

[aeajr]

Strange post. You somehow equate bagged wings with home built.

There are lots of ARFs that have bagged wings. And you can buy bagged wings whcih can be added to other components to make a complete glider.

[Andy W]

My flying buddy has won the e-nats many times with his scratch built, bagged wing designs. He gets beat now and then too, but not because "ARF's are better.."

He is in the minority. I could never spend the time it takes to build something like that. He puts hundreds of hours into them.

OK, perhaps when I retire..
..a

[Schwemmer]

I have been advised that moldies airfoils are more accurate than bagged. However with the advent of CNC cutting I just cant believe there is that much difference between the two. Or said another way, I would not know the difference between the two. My flying skills need to improve a whole lot for me to see the difference. I think the real reason is the time it takes to build vs time to install gear in a moldie. I have seen a pilot take a foam two meter and beat the rest of the group with fiberglass creations, you just know its the pilot not the plane.

Now I know that moldies will help me in my quest to be better, however practice will add to my skill levels more.

Sherpa

[aeajr]

Beautiful CNC cut bagged wings for those who would like to make a Supra at about 1/3 to 1/2 less than a molded Kennedy Composite Supra. No home bagging required.
http://www.stealthplaneworks.com/Suprawings.aspx


Nice bagged wing DLG ARF/kit
http://www.polecataero.com/products/sidewinder2

Bagged wing does not = home made.

[harleym]

Originally Posted by aeajr

Strange post. You somehow equate bagged wings with home built.

There are lots of ARFs that have bagged wings. And you can buy bagged wings whcih can be added to other components to make a complete glider.

Aeajr. . . I guess I should have mentioned that scratch-built bagged wings are something that can be done with little investment in equipment and are doable by a scratch builder. After doing my first one on my own, I learned the basics and from then on figured out ways to improve the results and fully documented it in the Genie web pages at http://www.geniebuild.com/harleys_genie.html.

Sure, I know commercial kits or ARFs with bagged wings are available, but going that route also defeats original thinking about airframe development and that is my point. The ARF, whether molded or bagged, stifles mass original thinking, so there is this great void in low cost, fine performing new designs that can be built by a typical modeler. Lacking such designs, those who can't afford or justify moldie costs commonly settle for older woodie designs.

Incidentally, having passed the bagging learning curve, I find I get about 20 hours, start to finish, into even a 12', 3 panel wing such as the largest in the Genie line. Written text tells exactly how to do it, so no one need be intimidated.

I am not aware of 3-piece bagged wings for the Genie line being commercially available. I only know of bagged wings made for NSP, etc. Aeajr. . .do you know of a source?

[rdeis]

Anker makes bagged wings for the Supra as well as 2m and XC airplanes based on the Supra.

He could no doubt be able to produce Genie wings, but I don't think he does now.

[harleym]

Originally Posted by rdeis

Anker makes bagged wings for the Supra as well as 2m and XC airplanes based on the Supra.

He could no doubt be able to produce Genie wings, but I don't think he does now.

Anker does not and I have never approached him about doing it. I worked with him about making incredibly accurate cores for the Genie line wings. With those available and the extensive instructions in the website, others can successfully do the pre-bagging and the bagging steps the same as I do. It has always been my intent to be instrumental in them doing so.

I find it intriguing to be able to scratch build a great performing, fine handling and eye-catching ship for $350 or so that can hold its own with anything in traditional thermal contests most of us go to. See attached pic showing
closeup finish on the wings of the Big Smoothie. Excuse the weird reflections and the low resolution. The pic does not do them justice. Except for LE finish, all painting was done on the carriers before bagging.

Those guys into F3B, etc. are in another world where expense for ARF's is no object.

[ozmo01]

There are many good reasons to go ARF or scratch build or kit build. It is all about what you enjoy. Asuming you enjoy RC GLiders. I have recently entered into the compsite or bagged wing building realm. Mostly for a new experience in building and because I choose not to spend the bucks for that level of ARFs. I have been able to aquire/ build / scrounge a new vacuum system and build a new feather cut type foam cutter.
As soon as I get the wife's new fron porch built I will start building a bagged wing Supra.
Of course you know no self respecting front porch is complete with out a 4' x 8' x 2" piece of blue foam

Here is a pic of the "Rube Goldberg" Vacuum pump. It works very well but it's no looker!

[rdwoebke]

Originally Posted by harleym

.I've built 2-3 a year for 17 years. Others who have built them are full of praise, too.

Check out the hand launch community. Lots of guys building thier own planes (including me).

Ryan

[Windependence]

Originally Posted by rdwoebke

Check out the hand launch community. Lots of guys building thier own planes (including me).

Ryan

Yep, it is my humble opinion that this area of soaring, I am referring to DLG, is the most innovative right now. There are a lot of people experimenting with home built creations. There are hundreds of threads on how to make a vacuum pump, how to bag a wing, how to make a fuselage. There is one thread I found where they looked into using a food saver system for the bagging.

Wayne

PS. Harley, I saw Augie M flying one of his Genie's in Minneapolis this past summer and I can attest to its competitiveness and its great looks. When I get a little more room in my garage I hope to try building one. I am currently using your fuselage as an inspiration for a scratch built 2 meter fuselage for an extra wing I have.

[Hostage-46]

It really is about time... I happen to contest one of Harley's ships, one he built. She's a gorgoues ship, I get compliments at every contest. My Genie SGP is a competative ship, that I expect to fly for years to come.

Fact is, there are only so many hours in the day. With work and family obligations if I want to fly, I just need to cut down my shop time. Recently I've been very deliberate in my attemps to cut downs shop time so that I can get more flight time.

When I complete LSF4 in the spring, I'll make a the move many of my buddies have with the check book, the Genie however, will remain in my quiver, like my Ava, I'll never part company with her!

[threcixty]

Remember, mouldies are "bagged" too! I do agree that bagged wings CAN be made to similar accuracies as moulded wings. I think that too much emphasis is placed on the whole CNC thing. Granted, I would love to have some shiny aluminum moulds in my shop, but all in all, dragging a wire across two accurate templates results in an accurate core, "plane" and simple.

It can be done, even with curved profiles. It can be done stronger and more efficiently. Remember that moulds are designed for production work. The surface finish can be brought within a few mills of a moulded wing if done properly.

Scale up a DLG and go for it. You innovators may actually open some eyes! Go win a contest with your $350 airplane and sell it for $1000!
Jim

[AndrewBurns]

In pure materials cost a bagged wing glider is going to be less than a top quality moldie, however when you factor all the startup costs (vac pump, rolls of various cloths, big tub of epoxy etc etc etc) it really does get quite expensive to just get to the point where you CAN make bagged gliders, and then there's all the wasted materials before you get any good! Not to mention time! I've been building a bagged wing 2m electric glider for ages now because I rarely have the time to do any work on it. On the other hand I own 2 really top quality molded DLG's and when you get down to it I probably couldn't have made those two gliders for less than I could buy them for, certainly not given the extreme quality and level of design behind them.

Of course I love a good build but there are a lot of legitimate reasons why people buy pre-made gliders and if you don't have the time or inclination to really churn out a few it's going to be cheaper too.

[rdwoebke]

Originally Posted by Hostage-46

Fact is, there are only so many hours in the day. With work and family obligations if I want to fly, I just need to cut down my shop time. Recently I've been very deliberate in my attemps to cut downs shop time so that I can get more flight time.

First off, I should say I have no problem with folks that buy or sell ARF molded (or bagged) planes. I say more power to them.

But that said, I always find that not enough time thing interesting. I guess it could well be that some people are just way more busy than me, but I usually have 10-30 minutes each day that I can devote to myself for fun stuff. If it is dark outside or raining when I can have those 10-30 minutes then I can't be flying anyway so building makes a lot of sense to me. For me personally I find it very mental healthy to take those 10-30 min each day and have never found a good way (for me at least) to store those up and convert them into 8continuous hours once a month kind of deal.

Ryan