AndyW

My Feedback: (1)

Milton,

I am impressed beyond words. Damn near professional. Sig or Cox sure could use a guy like you and we'd all benefit. Not that they don't put out great products but that stick and former work,,, man.

What CAD program are you using, where can it be got from and how much?

DICKEYBIRD

Aww shucks Andy, you're makin' me blush. Dunno if I could do it for a living though; I'm terribly slow and it would probably ruin the hobby for me as well. What would I daydream about while I was at work designing planes, designing more planes?

All you guys can do this kinda stuff. It's just a matter of taking a detour for a while and learning new things. That's what keeps me interested in this great hobby! The engine work you and others do is very exciting to me and someday I hope to build my own engine. It'll have to have some Cox parts though.

I use an old version of TurboCAD from IMSI that a friend loaded on my computer. It goes way back to the Windows 3.1 and early W95 days. Since the DickeyBird Aviation shop only has a 486 'puter with 32 megs of ram and my old laptop is a 486 as well, I hang onto that old version since it loads quick and flies along really well. It has a simpler interface than the later versions and seems to do well for my needs. Like piloting models, good results with CAD comes from the amount of stick time you put in.

TurboCAD LE and some manuals in .pdf format are available as a free download from http://www.al-ki.com/tcad/download.php#HatchPatterns It's a later version but I'm sure the basic tools are the same. If you're able to get a little help and learn the rudiments, you can buy it later on.

Good luck!

matchlessaero

I trained in highschool to be a draftsman (4 yrs), and I drew countless plans with graphite and velum...
When I got back into the hobby a few years ago, I was amazed at the stuff Dickeybird was doing on CAD. When he told me he was doing it with a Free program, I just had to try it....

There is a learning curve..., but if you can point and click on your computer, you can draw/design with it.

My favorite benefit of using CAD is the ability to resize things without erasing and starting over. Curves are much easier as well.

If you would like to try it, get a free program (like the one mentioned above, and start by taking a plan you drew on paper (or one that someone else did) and draw it in CAD.

Best of luck.

prole

My Feedback: (3)

I got really excited when I saw the post about the free download this afternoon and I've been trying to track it down all day. I can't get that link to work. Has anyone had any luck with it.


I took about 3 years of drafting and technical drawing in highschool as well. That was the art class that they offered for the nerds. It was fun, all of my nerd friends were there and the teacher was one of the most amazing people I've ever met.

I was pretty into going out and getting a T-Square and a drafting board for this design project but with the move and the expence of building the workbenches and setting up the shop I haven't really been able to spare the money or time.


I read about CAD in Flying Models last month and got really anxious to try it out. If that stuff that Dickeybird is doing is on a free program then I want in!!!


I've been google-ing all over the net today trying to get something here but I haven't had much luck.

Dickey- can you check that link out and see what the deal is....



thanks.


t

prole

My Feedback: (3)

man I do this all the time....


here is the link that works, should have kept my big fat mouth shut.


http://www.al-ki.com/tcad/download.php#HatchPatterns



Thank you so much Dickey, I'll let all of you know how this goes.




t

AndyW

My Feedback: (1)

Thanks guys for the help on the links. Got to visit them and learn this stuff. But, hey, Milton. Let me get this straight,,, you're using a 486? Isn't that like chopping balsa with a butter knife?

Geez ain't us 1/2Aers the most inventive, innovative, creative, talented, friendly, helpful, bunch of happy nerds on the planet. Makes you kind of feel sorry for the 1/4 scale guys. :cry:

DICKEYBIRD

Actually, since TurboCAD for Windows v3.01 came out way back when the 486 was a still hot machine, it works well with it. As a matter of fact, when I first began using it, it was an even earlier version which was optimized for Windows 3.1 and my friend loaded it on my old 386 shop computer. It had only 8 megs of ram! Man I was really happy when I was able to "commandeer" the 486 from the computer graveyard closet at work. It worked even better with the W95 OS. Other than a little slower loading time and an occasional lockup when I forget and have too many programs loaded at the same time, the 486 does great....and, I just plain like to use old stuff sometimes. It appeals to my Scottish (frugal) nature!

flyinrog

My Feedback: (1)

this is all too wierd here,, 2 years ago I took autocad at the local comm college for 1 year for the certificate and bought the light version for like $80 from the college so I could do my assignments at home ,hell I hardly remember how to now.....(more jobs than they could fill when I started, and I should take the 2 year course..no jobs when I finished the 1 year course and of the few guys that took the 2 year program I heard the same thing no work..but I was looking at modelcam even then, just couldnt justify money for a hobby at the time, still cant...maybe I should get back into it...Rog

DICKEYBIRD

Not much progress over the weekend to show & tell this time. The same problem occurs this time every year. Projects in the workshop are going pretty well, GREAT flying weather, then the dandelions and onions start attacking my yard! I spent most of the weekend mowing, trimming, spraying (30 gals. 24D) and not enough time building!

I got the gear mounting system done; my latest favorite style which I think I will use from now on. Pretty easy to bend, tough and serviceable if something happens.

DICKEYBIRD

Also finished both access hatches on the bottom of the fuse. The front one is just liteply, but I thought I would post how I make balsa hatches that are light but can be removed over & over without the screws crushing them.

I make the hatch to size then drill 4 holes in it with a sharpened brass tube and CA in short pieces of birch dowel sanded flush.

DICKEYBIRD

Once in place and screwed down, you can sand it in for a perfect fit. Oh, and try to leave a gap at the ends about 2 pieces of paper thick to allow for the covering.

Legend4

Looking good DickeyBird. My first plane (Sig seniorita) had that style of landing gear. Never rip it out once. Very forgiving!

SKYPYRO

WOW!!! That is all that came to mind when i saw that beautiful autogyro. I am wondering what kind of CNC machine you used, and how much a "cheapy" CNC machine would be. I really love the accuracy of laser cut and CNC machined parts, they speed up the assmebly by a lot. Thanks for your time, Dan

DICKEYBIRD

Speeds up the assembly; yes, but slows down the design/drafting a lot! It's almost a complete new hobby by itself.

I built mine about 5 yrs. ago for about $600.00 but they're cheaper now. Here's a link for a CNC discussion on EZone:
http://www.rcgroups.com/forums/showt...threadid=62920 It's a long thread but very informative.

Good Luck!

SKYPYRO

Thanks for the reply. One of the reasons that I want one is that I have about 5 or 6 hundred CAD airplanes, helis, and gyros just waiting to get built . Ill have to go check out that other thread, keep us posted on how that auto flies

-Dan

boberos

This message is for D.B. but I am posting here for others to benefit as well.
Conventional anding gears in the normal position work fine on twin rotor gyros.

However most guys are happy to hand launch the single rotor machines.
If you want to ROG a single rotor gyro, the landing gear must be well foreward, about even with the firewall, and quite long to assist with spin up. Both my DC Gyro & TravellersChoice have this set up & neither exhibits any ground looping tendencies what ever.
A steerable tailwheel is highly recommended. Otherwise take offs are very uncertain. Practice is needed.
Note that very few people do ROGs with single rotor machines.

Hal deBolt

Hi ya'll!
Posts and threads on this page bring up a wonder for me. Hope
is there would be someone who would have a logical answer.
The challenge is basics can be different from normal aerodynamics and thus take some learning to understand
So to this one>
Fundimental is that the advancing wing-blade sees greater air
flow speed than does the retreating blade. Thus we assume the
advancing blade creates more lift than the retreating blade.
We must trim any aircraft for straight and level flight?
With an airplane we would use ailerons or rudder to attain trim
needed to fly straight. Lets say use ailerons which relate to similiar action as a rotor.
The following is experience with numerous single rotor normal
Gyro designs and the reason for the necessity is baffleing.
In spite of a liitle bug saying no,no,no! With the Gyro in flight the
trim required for straight flight is to tilt the rotor towards the
retreating blade. The craft tends to roll towards the advancing
blade. thus requiring tilt towards retreating. No logic there?
Would appreciate inpuit on a couple of questions, thanks much!
1> Have you had similiar experience?
2> If so with what design? If not so what design?
3> If trim was required in what direction did you have to tilt?
4> Would you have a reason to explain this action?
Common sense does not seem to apply here, consider if we wish
to turn in the direction of the advancing blade we tilt the rotor
towards that and vice-versa.
5> could be why does the Gyro with neutral rotor want to turn
towards the advancing blade?
There is even more to all this but better for another time!
Mysterious?

Hal deBolt [email protected]

Digger-RCU

Hal Debolt? As in "StuntWagon" Hal Debolt?

Cause if it is, Welcome aboard!!!!

And guys, Show some respect. We have a genuine model airplane hero in our home.



Randy (Digger) Birt

wild fred

My Feedback: (3)

as in beercat and autogiro whiz Hal Debolt! anyway, Hal, could "p" effect have anything to do with it?

AndyW

My Feedback: (1)

All of this reminds me of a design in one of the mags some 20 years ago. This was, of all things, a single rotor, free flight
auto gyro. Imagine that. It was a scale model of a full size that the designer was building. I recall that somewhere, in the text, the author implied that it might not fly. Mine was fitted with an OK Cub .049. This was one of the originals with a beautifully anodized integral tank. NOT the junk that's being sold today.

At any rate, my gyro didn't fly either and I always wondered why. I found out soon enough but I then wondered why they would publish a design that couldn't possibly be successfully flown.

Much more complex rotor heads or twin rotors are the answer. However, has anyone considered a twin rotor with both rotors on a single shaft with the rotors turning opposite each other? The only problem I can see is the lower rotor's wash affecting the top rotor. A number of experiments could be tried like varying the size, or speed, or blade area of the two rotors.

DICKEYBIRD

I did a scratch built one with coaxial counter-rotating blades with an OS .15 back in the middle 80's which was a disaster. My flying buddies loved it 'cuz they all got a good laugh each weekend as I tried various things to get it to fly. We used it in one of our video segments but I had to edit together about 7 or 8 separate short clips to make one successful flight! It NEVER did successfully take off, climb out, flyby and land all in the same flight.

I have seen a couple of coaxial type 'gyros in mags that were said to be successful but I've had enough of 'em! Mine had heavy blades and I guess the different acceleration characteristics of the 2 different diameter rotors and the turbulent air going through the upper rotor caused weird things to happen as it speeded up and slowed down.

2fast4u

My Feedback: (5)

DICKEYBIRD, Have you not seen the twin rotor auto gyro that has flown at SMALL for the bast 3 or 4 years? It flys great!! It will even roll. I could try to find the owner if you need me too. I think he lives here in Little Rock.

AndyW

My Feedback: (1)

Thanks Milton,

I kind of thought you might have tried that.

Mr DeBolt,

Just so that we understand. Logic dictates that, because the advancing blade produces more lift, the gyro should tilt, or roll, to the opposite side. Are you saying that your experience contradicts this? Is this with RC or controline gyros? If controline, logic would dictate that you want the advancing blade on the inside of the circle. Presumably this would help keep the lines tight. Or, have you found the opposite to be true?

DICKEYBIRD

You talkin' about this one, or it's yellow colored, shoulder "wing" predecessor? Both designed, built and flown by long time buddy Brian Pate (spindr) & son Michael. We installed larger wheels, adjusted incidence, and strengthed (don't ask!) the "wing" on the "Spin Doctor" and have it taxiing, taking off, landing and doing touch & goes....all on a grass field. Getting ready for S.M.A.L.L.!

The yellow one was sold at S.M.A.L.L. '02 to a fellow in the L. Rock area, I forget his name....I assume it's still flying...it has a "DickeyBird" Cox TD .049.

ps: Speaking of Brian, he's in the hospital with a severe foot infection; so be thinking & praying for him. I've already told him ain't no way I'm shoving him around S.M.A.L.L. in a wheelchair so he'd best do what the cute 'lil nurses tell him to do and get his arse well!

DICKEYBIRD

Geez, between mowing, spraying weeds, and planting a Dogwood tree; not much time left for 'gyro building. Didn't get much done but here's some pix:

This shows how to build a triple tapered wing (in this case, a h/stab) that is straight and true without jig rods or building tabs. I call it the "Outlaw" method since the 1st time I saw it used was on a Jerry Smith Outlaw delta.

The heart of this method is making the leading & trailing edge blanks wider than needed (I used 3/16" by 5/8") with a 1/16" square strip glued on the inside center so that the ribs (which have corresponding 1/16" square notches cut in the center of the front & back) can be indexed & glued easily in the exact center. When the ribs & spars are in place, the entire piece can be picked up and turned over for further work without any fear of warpage.