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I'm a total noobie to this, but It blows my mind that some dedicated engineering type (which clearly this type of project attracts) hasn't taken plans for these aircraft and , using a CAD package, put it in to dwgs, dxfs, or something similar. This is a perfect application for AutoCad, and obviously somebody has the time on their hands to accomplish this.

Why would someone pay 500 bucks for plans to a plane if the prints looked like they were scribbled on the back of a napkin? It is far easier to move digital info than paper... and far less expensive. Has anyone attempted this

-- my $0.02

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Don't confuse form with content. A CAD system is nothing more than a really fancy pencil. CAD lets you produce nice-looking drawings easily. But that's it. It doesn't help you make the actual design any better.

 

The engineering that went into the design of the EZ aircraft and the Cozy is plenty sophisticated.

 

Exactly what, besides aesthetically pleasing drawings, would actually be accomplished by taking the existing plans and putting in a lot of effort to convert them to CAD? Sure, you could drive a CNC machine with the file and automate the cutting of parts (people HAVE done this), but in the real world how many of us have access to such equipment?

 

The thousands of aircraft built using Burt and Nat's plans are living proof that the existing plans work just fine.

 

A great many very fine aircraft were designed without the benefit of CAD. The drawings for them were all done by humans, using manual tools.

 

Such as, hmmm...the SR-71.

 

Oh, by the way: there are some CAD renderings of certain parts of the Cozy over on Marc Zeitlin's site.

 

There have in fact been homebuilts with drawings that were prepared using CAD. The one that comes to mind is the Prescott Pusher.

 

Don't recognize the name? Not surprising. It showed up in the mid-80s and faded pretty fast. CAD doesn't make the airplane any better.

======

Not started yet, maybe never will (currently having an affair with an RV project...shhh...don't tell my set of Cozy plans)....

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The engineering that went into the design of the EZ aircraft and the Cozy is plenty sophisticated.

 

---> No more sophistication than the sophistication required to understand composite design. I think you'd be shocked to find that RAF didn't spend alot of "design time" on the Long-EZ. And Nat sure as hell didn't do any sophisticated design effort on the Cozy. RAF simply took what they knew about composite construction and "built" the Long EZ to what they knew would work, plus a little more to account for builder variances. Yes, there was design work, but not "sophisticated" design effort. Heck, the canard was tested to failure years after the first builder Long EZs were flying. To date, they've never tested a Long-EZ wing to failure.

 

After the Voyager landing, Dick Rutan was asked by a reporter how he knew the Voyager would make it around the world. Dick replied (paraphrasing) that his brother Burt had done all the design and stress analyses. Burt, standing nearby, can be heard chuckling in the background. The reporter leans over to Burt, and Burt says, (again paraphrasing) no, we didn't have time or money to design things. The reporter asks, well, how do you.... Burt says, it just looked right to me. If you've ever seen the documentaries, you'll see that alot of the basic stress analyses and design efforts went into the Voyager's spars and the number of plies required in the wing skins. Very little after that. One scene that makes me chuckle is when one of the fabricators is asking Burt about what diameter the lightening holes in the bulkheads should be. Burt takes out a sharpie pen and free-hands an outline on the bulkheads. He says, "about right there". The fabricator takes out the jig saw and cuts the hole.

Wayne Hicks

Cozy IV Plans #678

http://www.ez.org/pages/waynehicks

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I agree with you on that point. It's just that if you need more than one copy of the prints for construction purposes, or for the sake of keeping the plans in circulation, digital might be the way to go. I have never been up close and personal to a set of plans for one of these, but I keep hearing about ppl who have a need for spares of templates, etc. and offered a solution.

Of course youare about as likely to have access to a wide format printer as you are a wide format copier, but as far as Iknow, the plans are only "B" size prints any way, right?...Out of curiosity, what scale are the drawings typically?

Has anyone gone though the trouble of building a solid 3D model of a Canard homebuilt?.. maybe this message should be in a different thread...

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Actually, Wayne, I was referring to the shape of the plane (aerodynamics), not the structure. Not really the central point anyway....

 

Regarding the plans format: The plans books are 11 x 17. The drawings for the LongEZ are 18x24, and there are 14 of them. The supplemental plans for the LongEZ are a variety of sizes.

 

RAF is closing its doors if it has not done so already. They are the source for the supplemental plans (e.g. Roncz canard, long rudders, internal bellhorns, etc.).

 

These plans also are available on the RAF CD-ROM set, available from TERF or AS.

 

Regarding copies: If you do some digging in the archives, you'll find cautionary tales about dimensional inaccuracies created by copiers. I believe that this is less of an issue with newer copiers than it once was. I recently bought a full set of LongEZ plans (complete with an unused license, even). They're so old that I fear the paper will start to disintegrate if I actually try to use them regularly, so I did some test copies on one of our machines at the office, and the proportions appear to be perfect.

 

If you go with a Cozy, for 50 bucks Aircraft Spruce will sell you an extra set of the template drawings, which are in fact derived (where possible) from the DWG files on Marc's site. Worth the money.

 

Lots of people just use tracing paper to make copies.

======

Not started yet, maybe never will (currently having an affair with an RV project...shhh...don't tell my set of Cozy plans)....

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Why would someone pay 500 bucks for plans to a plane if the prints looked like they were scribbled on the back of a napkin?

Good question, and good thing that none of the plans that I have seen (Long-EZ, Cozy, AeroCanard, Eracer) look like they were scribbled on the back of a napkin -- they're all very good (with the Cozy plans being the best IMO).

 

It is far easier to move digital info than paper... and far less expensive. Has anyone attempted this

This is by design -- the same design as that used by book publishers so that they have a physical means to manage their product. It is a definite expense to produce CDs/DVDs so that they cannot be copied, and an expense that might not be worth whatever ROI would be gained.

 

With all that said, I do agree that the plans could definitely be updated and reworked. I'm just not sure it's entirely necessary to make things easier for me right now. If they were updated, sure, CAD files would be nice, but the real priority (if you ask me) is not to change their layout -- it's to incorporate all the proven modifications that builders have since developed on their own.

 

For $50 I was able to get a complete new set of 1:1 drawings from Aircraft Spruce that I was able to cut up and use for building. If I had DWF files, I'd have to:

  • Find someone who could print them for no more than $50
  • Verify that their printer produced accurate proportions and aspect
The plans aren't digital, but they're very well good enough. They also will likely represent less than 1% of your total expense.

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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If the CAD drawings don't exist by now, they never will (at least from the manufacturers). Its an expensive, time consuming thing to do and it would make all too dang easy to pirate.

 

Now the other ugly aspect of doing this. It slows you down from building the plane!

 

After talking to Nat at Sun-N-Fun, he really frowns on people moving away from the plans. Besides the fact that builders may make mods that are less than wise, these also increase the build time. Nat believes you can really build this plane in the time specified if you stick to building the plane and not putting in mods.

 

Be aware, that Nat's own bird has an electric nose lift.

Nathan Gifford

Tickfaw, LA USA

Cozy Mk IV Plans Set 1330

Better still --> Now at CH 9

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it would make all too dang easy to pirate.

 

 

It's not like you can go down to your local Office Max, and have the templets printed out. Even if they did it would probaly cost you about the same. If we had access to the DWG file it would make like a lot easer to mod.

 

*.DWG are the indistory format for CAD file. It will alow any CAD program to read the file(s)

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I think we all have thought about doing that ourselves. I'm building so there's no time. How about one of you "don't know when I'm gonna' start" guys. I'm sure we'll all put you on a pedestal. Heck, I bet AS&S gives you the percentage of the "revised" edition. Aerocad is a good start too. That one cracks me up. I thought I was going to get my drawings on a disk. Instead I got the "notebook" edition of the Cozy drawings.

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Aerocad is a good start too. That one cracks me up. I thought I was going to get my drawings on a disk. Instead I got the "notebook" edition of the Cozy drawings.

Ah, a perfect example of good plans gone bad. I MUCH prefer the big-book style of the Cozy plans that are NOT written in 'FinePrint font'. I compare the Cozy plans with the plans-built AeroCanard plans for everything I build. Here are some issues with the AeroCanard plans:

  • Some dimensions are not clear as to whether they're for the FG or the SB (Cozy Mark IV size).
  • Some dimensions are not carried over from the Cozy plans. The one example I know of can be picked up on another page in the plans.
  • To make the "reformatted AeroCanard" plans, OCR was used, which leaves for some interesting results. For example, "The forward f3ce gets 2 plies of BID..." Now that's an easy one to decode, but now how confident are you that the #MS24694-S54 screws are properly identified? BTW, they are.
The fix is easy -- buy the Cozy plans too. I'm also very hopeful that the new AeroCad owner will be doing a MUCH better job than Jeff was able to in the last few years with regard to growing the business, making improvements, and addressing issues such as these.

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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