RC plane Design and build

Here are some examples of what I have finally been able to achieve in Fusion.

Have you found a way of applying a surface for the covering material. I tried offset surface and patch the the open space with some success and spectacular failures.

I always start with a full solid model of the entire aircraft. Then "chop" it up into ribs, formers, skin, spars etc. much like Roy does. To get the covering, go back to the starting solid of the entire aircraft and shell it with a very thin thickness. This can then be colored and decals applied as needed.

Thats probably the easiest way to do it. I always duplicate my solid bodies, and keep them, just in case.

You could also do an offset of the solid body and thicken it.

This is about what the result looks like. Ignore this color scheme. I threw it together from scratch in about 15 minutes since I don't normally model the covering. By the way, I'm aiming more towards the Swiss Air Force scheme.

Depending upon your display card and settings, a thin layer like this may not display correctly. Mine looked terrible until I actually did a ray-trace rendering.

I use Inventor and do a top down design proccess. Everything is derived from, and remains linked to, the base solid model. If I change the base, all parts update to match. I'm not sure if Fusion has this capability.

By the way: Your techniques and tutorial videos are top notch.

Yep, I tend to design outside in. With Fusion, you can alter the design by going back and changing things in the timeline.

Have you posted any of your designs?

Not yet. I guess I need to.

And the next question of course, have you built any of these?

This is my current build:

https://www.rcgroups.com/forums/showthread.php?4157239-Direct-Connection-F-20-TigerShark-F-5E-Tiger-II

I had never thought of keeping a complete solid body. normally I am working from paper plans or similar then extrude or loft all of the parts.

I do like the idea of working from a solid body for covering simulation.

I remember seeing the ads for that plane way back in the old days!

It's looking really nice!

I wonder if I can do my weight and balance in Fusion?

What do you use to drive your laser?

I'm "printing" everything for the plane from AutoCAD 2022. (Anything art related goes through Coreldraw.)

1. I design everything in Inventor.
2. Export the patterns out as an AutoCAD DWG file.
3. Clean up and seperate all patterns into their own DWG file.
4. Import the individual part patterns back into Inventor for automatic nest generation.
5. Export the nests as DXF files.
6. Import the DXF nest files into a preconfigured DWG file with the drawing limits and layers preset.
7. Put everything onto the proper layers
8. Print the DWG to the laser from AutoCAD.

That sounds quite convoluted but Inventor does an incredible job of automatically nesting the parts on a given sheet size. However, it can't create nests from anything with splines and the patterns are spline heavy. So I have to convert the splines to polylines in AutoCAD. I can't "print" to the laser from Inventor so everything has to go back to AutoCAD in the end.

The nesting environment in Inventor is relatively new. It's got quite a few bugs to be worked out. I'm hoping they make some significant improvements soon.

I designate all materials and when installing things like servos and other easily moved items I follow up with "Center of Mass".

Might only be close as I haven't weighed actual engines against the 3D models however if the center of mass is within a half inch or so and where I expect it to be then I know things are going well.

I weigh all components and override the calculated weight for each piece. However for balsa and plywood, I let the CAD system calculate the weight after I’ve entered the density. Since the collective CG for balsa and plywood components is already near the center of lift, errors are insignificant. It’s the subcomponents that matter: engine, servos, batteries, etc.

That does sound like quite the process to get to the laser.

Fusion can nest, but I've not tried it. There is a website that can nest, but I've not messed with it enough figure out if will account for grain orientation.

After I flatten all my parts, I create a sketch of them and export that. Then it goes into Lightburn, where I manually nest.

It's not too horrible.

Inventor allows input of stock size and inventory. It will actually spread the patterns across multiple sheets of different sizes. You can set allowable rotations, mirrors and tolerances. I can tell it to automatically mirror or rotate as needed. Rotation doesn’t have to be exactly 90 or 180. You can set a tolerance +- some amount. You set quantities, margins between parts and the edges. Then press go. Unless there are only a very few parts, it does a much better job of nesting than I could ever do. For some reason if there aren’t many parts then the nesting seems to be quite poor. But in that case I’d be better off doing it manually anyway. The nest program maintains a link to the original pattern so if a pattern is updated it will be automatically updated in the nesting program. In spite of the steps I have to take it actually saves a lot of time.

Interesting...

Now, you're inspiring me to mess with Fusion's nesting function.

Wanted to share my updated color scheme.