John,

There has to be!

Years ago I would make the tip rib and the root rib attached to the LE and TE. Tape them off top and bottom. I would then put all the other ribs in, rough cut. Using a straight sanding bar, I would sand the ribs down till the sandpaper touched the two taped end ribs.

Didn't take long to do and it worked. Had to have a good eye for sanding.

With my drawing program, I can layout the actual rib, length and thickness of the root rib and the tip rib.

Say the ribs are 2" apart. I would then have to determine the length of each rib, but my software will scale the rib to the proper measurements for that length.

20 ribs, I have to do it 20 times. I can't do it with the spar cut in, because the rib gets smaller with the scaling. It's a pest.

There is a hot shot guy on another Thread that has nice plans drawn. He says he uses Corel Draw. He also says Corel Draw does all his ribs easily. I asked about it for an explanation, but it seems I have a long waite for the answer.


My old method still works, because you can actually assemble the wing, LE, TE and spars. You have to cut the ribs and sand them anyway, so, just rough cut, assemble the thing and sand away.

I've done many wings this way. Then there were hot wires.

CB

To: "Avaiojet"


As I said in the "other thread" I don't have the slightest idea who you are since you have made a secret of your name.

I do not appreciate being insulted and being called a "Hot Shot"!

I have published articles in American Modeler, Flying Models, Model Aviation and Stunt News, and I am a past District VP in Pampa. I have been making Quality laser cut kits and rib sets (Blue Sky Models)  for the last seven years, and have sold them internationally.

Corel has a blend function. Draw the top of the rib, use copy and paste and flip over, snap to guide lines to make an identical rib bottom.
Then for each section of the rib click on top, shift click to show root & tip together. Now use the blend function to show number of ribs in between. The root & tip MUST have the same number of nodes. Then click on the newly created rib sections and separate them so that you can layout each rib section separately.
Now you are on your own. There are other things to do to create proper cutting tolerances an alignment of slots and spar notches. But again you are own since tolerances etc as proprietary.   

I am well respected by most in the Stunt community, and don't appreciated being called "some hotshot". Particularly by some one who won't tell us his name, when it is required by the forum.

I will say no more.

I have one of Tom's Falcon kits, as we are both admirer's of John D'Ottavio from 50 years ago.  His quality is unmatched, period.  PLEASE can we not have a mudfest?

There is a hot shot guy on another Thread that has nice plans drawn. He says he uses Corel Draw. He also says Corel Draw does all his ribs easily. I asked about it for an explanation, but it seems I have a long waite for the answer.

CB

"Avaiojet",
The tool you'll have to use to draw tapered ribs (or whatever shape you want) is called "Interactive Blend" or "Interactive Mix" (the one that has the little squares one behind the other).
1. Draw root and tip ribs first.
2. Select the tool.
3. Locate the cursor over any of the ribs (root or tip, it's the same)
4. Left click and drag it to the remaining rib.
5. Go to the toolbar at the top of the page and enter the number of ribs (tell the program how many ribs you want in between).
6. Done!

Avioajet, A couple of notes that should interest you. I believe  you may have inadvertently made some comments that have touched others slightly off center. I suspect that was not your intention. Probably just the way you express yourself.  In any case, as you've probably seen, in the on-line world, where we are in electronic contact, It almost requires the use of those pesky emoticons to convey your intentions.

As you're aware, Tom.N. is one of the good guys. But I can say he's not to  be trusted , and get away with it because everyone knows I'm kidding around by the emoticon.

I am interjecting this in an attempt to offer a little help, so you don't get branded as a goofball. Personally I believe you have a lot to offer the members of this forum.

To John Rist's question, You've been offered good advice, but I would like to take it a little further.

There are software, such as Stunt Rib, developed by our own Larry Cunningham that will generate a rib set, and can be downloaded for free from the PAMPA website. There's also Profili, another rib generating software with both a free version, and a paid version available for download on the internet. Both generate files with .DXF extensions that can be imported into most vector graphics programs.

Your choice of Graphics programs is of course, often a personal matter, but, my choice is to use a CAD program, as that is where my training is. An on line seqarch will reveal many available programs for no, or a small fee that can be downloaded from the net. I would suggest that you consider those who claim to have compatibility with, and work similarly to the Auto Cad products. It is the fall back system of choice for the personal computer users.

One I'm familiar with , and use, is called Double CAD. It's offerred by the same people of make Turbo CAD, which also has products that emulate Auto CAD as well. The Double CAD product downloads a full featured version for you to try for 30 days. After that it reverts to a simpler version, but continues to work well enough for our uses.

Files generated by the previously mentioned Rib generating software, can be imported into the Double CAD program, where it can be used in a design, or printed out.

In the case of the plans I draw, I use a program called Compufoil 3D pro. It's a commercial soft ware program that is very powerful, contains hundreds of airfoil COORDs, that can be modified if needed. It also has a generator that will generate any of the NASA series of airfoils, like the 4,5, and 6 digit 'foils, as well as modify them, it will then loft out all the ribs to your requested parameters, and produce not only the individual ribs, but draw the top view of the wing for you. It will also render the wing in 3D if you want.

It isn't a free program, but the cost is reasonable for what you get. You also have to "play" with it to learn the features, as there is no manual. It's OK though, as most is very intuitive, and the controls are pretty self explanatory.

So, I hope this helps.

I've got Corel Draw 6 on a Mac, I can't even find the pencil to draw a line.

Ribs in Adobe Illustrator? I don't think so.

I use a great program for producing signs, graphics and cutting vinyl. It's $3K. The upgrade is $1K and that won't do ribs either, just gives me large format printing options and runs on OS 10.

It's not designed for ribs.

Here's the thing. If the rib drawing program is in vectored format, you have a means to have the ribs laser cut. Great advantage.

I'm not sick of old school, I just don't have the time for it. 
 
CB

Hi Allen. They are both products from the same company. The difference is that Double CAD feels more like Auto CAD LT and accepts many of the same short cuts and techniques.

Turbo CAD has gotten their stuff together better, offering a good study course on CD. I believe Double CAD has a similar course. Since I studied AutoCAD in school, I'm most familiar with executing the program vagaries under that style of diddling. 

I think that the best suggestion for someone who wants to become really profficient in a CAD system, would be and take classes at their local adult education, or Community College. You'll probably be trained in AutoCAd, but, a bit of additional study with Turbo, or Double CAD, and one should be OK.

Most of us seem to lack the dedication to school ourselves enough, before trying to use the software. That's been my problem anyway, when trying to get profficient with these other systems.

Try it out, the down load is free. 

Shame Larry Cunningham hasn't updated his program StuntRib.

d

John and John, thanks for that.

My software does allow for "easy" making of ribs, even tapered ribs. I can, drop in the LE size and TE size after. even for laser cutting.

The spar cut out has to be placed afterwards also.

The rib openings do not, they can be scaled down as the rib sizes get scaled towards the tip.

My advantage is I'm vector. Save the thing in DXF and off to the laser cutter it goes.

I do drawings that go to modelers, both for plan outlines and details, which can go to laser cutters.

I'm working a 144" span model as I write this.

The rib drawings are a killer, they take up a bunch of time. Only tapered wings I should add.

Thanks for that info.

CB

I was surprised that no one mentioned Profili earlier.

I use the simple version to lay out airfoils I generate by modifying established airfoils in Profili or create from scratch as corrordinates. It very quickly lays out ribs for tapered wings of any number of ribs with the same or different root and tip sections. It has a vast library of sections, including the most often used NACA subsonic sections (4-, 5-, 6-digits). It allows you to put parts of two sections together to make a new section and to deform stock sections into new ones by varying the position and relative thickness of any point along the chord. Within certain limits the simpler Profili will also place spar cut-outs and I THINK will also print out rib series for elliptical wings. Of course, if you do not choose to space ribs regularly, or have a different wing plan form, you can compute your individual rib sizes and then print out the appropriate intermediate ribs separately. The nice thing about any wing section you come up with is that Profili generates aerodynamic polars and L/D graphs and compares sections for you in XFOIL, which is a part of the set. It's pretty cool, and Stafano has always sent it or its mods to me promptly (like same-day) when requested, including my initial contact which, back then, required me to contribute $10 (might be $12-15 now) later via mail. It's basically free and a huge bargain. I've used it to generate ribs for all my self-designed planes as well as to contour stub ribs to insert between ribs of my P-Force kit wing.

Of course the Pro version is much more versatile and larger in scope. I will get it when I really need to go farther. Finally, you need no particular skills to use Profili, past knowing what you want to do. It's very easy to use - pretty self-explanitory - and can be employed by anyone immediately upon opening it.

SK

I use it also, but my sign program has better offerings and features. Much quicker also.

How do you maintain consistent openings for the LE, TE and spar, as the airfoil decreases in size to the tip, both thickness and length?

CB

I just did this in Inkscape.  The airfoil is very ad-hoc: basically, I just whomped it up.

But notice that the spar cutouts stay the same from rib to rib -- that happened automagically, using Inkscape's "intepolate" command.

Or what if you couldn't decide between free-flight duration and control line stunt?

Interesting.

I see you don't have cut outs for the LE or TE.

I whomped it up for a demonstration!  And besides -- it's squared off at the end for the TE sheeting.

Would that make a difference with your program?

I don't think so.  My total experience with that feature is generating those two plots, but I'd be mighty surprised if cutouts for the leading edge (and for sheeting) didn't work basically the way that the spar cutouts did.

You do free flight?

I'm not smart enough.  Although the son of my RC and CL flying buddy flies FF, and I'm picking up stuff from him.

'forgot to mention: Profili also does leading edges and sheeting of any dimensions. - SK

Serge,

I just figured it out. I'll send you the measurements, airfoil diagram, and you can draw my next wing? 

Can you save the drawing as a DXF, so I can have the parts laser cut?

CB

I just loaded my copy of Profili.