With respect to the Don Stackhouse of DJ Aerotech (whose fine product I have purchased), and other manufacturers, I think some serious questions regarding scratchbuilding have been raised. I appreciate and support the hard work and financial risk that the model suppliers invest in keeping us supplied with our 'toy' aircraft, but I also feel that the scratchbuilders among us were perhaps a bit shortchanged by some of his comments (repeated below). I have built from kits, and I have also done some scratchbuilding, in large part for the satisfaction of developing and using some manual craft skills, and also just for the pleasure of seeing garage 'junk' turned into something useful. I know full well that I am not saving any money, and in fact, have probably spent more than the cost of a kit or two in completing a given project. I might even have had to buy or build a tool I wouldn't otherwise need. But my son and I had a hell of a lot of fun learning the techniques of foam cutting, wing bagging, etc. And frankly, its kind of fun to be able to brag that I can build an flying wing (boomerang) in 2 evenings from some housing insulation and tape for ~$5 in materials and call it the "five dollar foamie". The plane flies kind of crappy compared to the commercial product, but I know there are more where it came from when I bash it up, and that perhaps there are some mods I might try just to see if I can get it better (or different). Yes, perhaps, I was immoral because I found an airfoil that fit the commercial wing I had purchased, and I traced the planform, nor could I say I even understand the aerodynamics of flying wings. But I was able to produce a plane that I could claim I built from the ground up. Furthermore, since I have no commercial aspirations in my activity, I feel I have 'fair use' of a design. (Patent attorneys need not respond!) As a matter of fact, one of my current projects has been to build something along the lines of a Red Herring so that I can backpack it into some remote slope and have some fun. Frankly, at this point, my efforts so far have been spectacularly unsuccessful--the creature flops around like a grounded goldfish, demonstrating that I currently have no understanding of how flying wings work. But either I'll spend some researh time and figure it out, or give in and buy a kit. Either way, I will have spent a lot of pleasant constructive hours with an excuse not to watch TV. I might add that scratchbuilding with my teenage son was a fantastic experience. He is one of the few kids I know who actually have learned how to use their hands with something other than with a video game controller. He's learned, among other things, about strength of materials, composites, CAD skills, and organizing a project--and he's now enrolled in a university engineering program. I can thank building model airplanes on all levels for that motivation. This hobby being as complex as it is, I actively support modelers going out and buying the kit or even prebuilt aircraft, but if one has an interest in striking out on his own, I see nothing wrong. Maybe a given manufacturer will have lost a sale or two, but I can assure you that someone will get my money! By the way, the airfoil for the Red Herring is a modified SD7003, but Don is right, that info alone won't help. The info is on the www.tgworks.com website. Richard Shagam Albuquerque, NM From: Don Stackhouse @ DJ Aerotech <[EMAIL PROTECTED]> Date: Tue Nov 28, 2000 12:54pm Subject: Re: [RCSE] HLG in the form of flying wings Mike Carris writes, with regard to the Thermal Grommet Works flying wing HLG's: >50 sec dead air times with a 34" glider of any configuration seems amazing? Maybe I should try one of these. Do you know the airfoils, I would like to build one.< There are a couple things wrong here. 1. The moral issue. Adam Weston and his friends made the necessary HUGE investment in developing a good model, turning it into a kit, putting together a company, building tooling and equipment, buying materials, etc., and now that they've figured out a design that works plus gone to all that trouble, effort and expense, you want someone to GIVE you some of the parameters of the design so you can try to "copy" it. 2. The practical issue. There's FAR more to the design of a sailplane than just the airfoils. In fact, airfoils are a relatively small part of the total picture. If taken outside of the context of the rest of the design, knowing what airfoil(s) are used is essentially MEANIMGLESS trivia. If you started with just the knowledge of the airfoils used and an approximate idea of the size and shape, what you would end up with would in all probability be a poor imitation of one of TGW's kits. Odds are that you would have to build and test several prototypes before you got something even close from a performance standpoint, and at that point you would probably still have quite a bit of work yet to go on getting the stability & handling right. By the time you were finished, you would probably have invested far more in blood, sweat, tears, and material $$ than the price of a kit. If you want the experience of designing your own airplane from scratch, that's fine. However, don't fool yourself into thinking you've accomplished that by trying to copy someone else's design. Make the effort to study the engineering issues and develop a design of your own. That's how you get that feeling of true accomplishment. Copying someone else's design is like copying off of someone else's test paper in class. Even if you get an "A", you will know that you don't really deserve it, and that you're benefitting illicitly from someone else's work. The only way to feel like you've accomplished something worthwhile is if you put the same sort of effort into your own design that someone else had to put into theirs. If, OTOH, you want a model that flies well and don't want to spend any more than you have to, then don't fool yourself into thinking that scratch building will be a quick and cheap route to that goal. Unless you are very lucky, you will end up spending far more to get to the same level of performance, handling and fun than it would cost if you'd just bought the kit. When you buy a kit, you're not just buying the materials in the box; you're also buying the value of all the engineering, investment and effort that went into developing and producing that kit. In most kits, the value of those "intangibles" far exceeds the portion of the kit cost that's allocated to them. If you really want to see the state of the art continue to advance, allow the folks who do the work, and make the sacrifices, to reap the rewards they deserve. Don Stackhouse @ DJ Aerotech [EMAIL PROTECTED] http://www.bright.net/~djwerks/ RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
