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64mm EDF FJ-3 Fury

#1
Starting new project since I had to go home due to all this Corona stuff and couldn't take the P-39 with me. I'll be building a 64mm EDF FJ-3 Fury. I'm building the fuselage around a duct running from the inlet at the front to the exhaust. The goal is to try to optimize airflow so I don't have to use cheater holes. I've got most of the CAD done (stuff hidden in picture to show the duct and formers) and starting the build itself tomorrow.



Fury.png
 
#2
Cool new project. What do you use to convert your model into 2D plans? I think I've seen on a previous post that you use Solidworks for the cad part, but what's your process for getting your 3D model down to 2D? I'm specifically interested in the skin panels.
 
#4
Cool new project. What do you use to convert your model into 2D plans? I think I've seen on a previous post that you use Solidworks for the cad part, but what's your process for getting your 3D model down to 2D? I'm specifically interested in the skin panels.
Ah so for that, Solidworks has a cool tool that allows you to take the face of a 3d model and flatten it into a surface model. It's the flatten tool, and from there, I export the newly flattened surface model into a dxf and open in autocad (inkcape works the same, I just use autocad since I have a student license anyways).

Here's an example using a duct piece:

At the bottom there's a slit running down the length of the piece, this simulates where you would glue it after molding.

duct sample1.png
Next you select the "Flatten" feature, it's located under the surface category of the "insert" tab. To use the flatten feature you just select the faces you want (highlighted in blue) and the vertex for where you want the unfolding to begin (which is why you make the slit in the model, it breaks the continuity of the part and allows for it to be unfolded).

surface.png


And from there you are left with an unrolled version of the 3D part. Next you just have to right click the part and hit export to dwg/dxf (doesn't matter which since both autocad and inkscape use either). The great thing about this is the geometry will be exactly how you want it and you know exactly how it will fold up.
 
#5
Very nice. I used to have a student license for SW when I was at uni, but alas all good things end. I'm using Fusion360/meshmixer to try to do this exact process at the moment. Hopefully it will work, but I've noticed some differences between the dimensions of the model and the flattened pieces that I'm getting out of meshmixer.

Do you ever have to scale some of the pieces slightly to get them to fit properly IRL?
 
#6
Very nice. I used to have a student license for SW when I was at uni, but alas all good things end. I'm using Fusion360/meshmixer to try to do this exact process at the moment. Hopefully it will work, but I've noticed some differences between the dimensions of the model and the flattened pieces that I'm getting out of meshmixer.

Do you ever have to scale some of the pieces slightly to get them to fit properly IRL?
When I was building the airacobra I didn't but this one I did. But the issue ended up just being me screwing up the print settings not the scale of the parts themselves.
 
#9
Ah so for that, Solidworks has a cool tool that allows you to take the face of a 3d model and flatten it into a surface model. It's the flatten tool, and from there, I export the newly flattened surface model into a dxf and open in autocad (inkcape works the same, I just use autocad since I have a student license anyways).

Here's an example using a duct piece:

At the bottom there's a slit running down the length of the piece, this simulates where you would glue it after molding.

View attachment 166902
Next you select the "Flatten" feature, it's located under the surface category of the "insert" tab. To use the flatten feature you just select the faces you want (highlighted in blue) and the vertex for where you want the unfolding to begin (which is why you make the slit in the model, it breaks the continuity of the part and allows for it to be unfolded).

View attachment 166903

And from there you are left with an unrolled version of the 3D part. Next you just have to right click the part and hit export to dwg/dxf (doesn't matter which since both autocad and inkscape use either). The great thing about this is the geometry will be exactly how you want it and you know exactly how it will fold up.
Hi
Just spotted this,does it definitely produce the right size skin,I've been using fusion 360 and mesh mixer and run into problems
https://forum.flitetest.com/index.php?threads/help-unwrapping-on-fusion-meshmixer.62379/#post-577599
Thanks
 
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#10
Ah so for that, Solidworks has a cool tool that allows you to take the face of a 3d model and flatten it into a surface model. It's the flatten tool, and from there, I export the newly flattened surface model into a dxf and open in autocad (inkcape works the same, I just use autocad since I have a student license anyways).

Here's an example using a duct piece:

At the bottom there's a slit running down the length of the piece, this simulates where you would glue it after molding.

View attachment 166902
Next you select the "Flatten" feature, it's located under the surface category of the "insert" tab. To use the flatten feature you just select the faces you want (highlighted in blue) and the vertex for where you want the unfolding to begin (which is why you make the slit in the model, it breaks the continuity of the part and allows for it to be unfolded).

View attachment 166903

And from there you are left with an unrolled version of the 3D part. Next you just have to right click the part and hit export to dwg/dxf (doesn't matter which since both autocad and inkscape use either). The great thing about this is the geometry will be exactly how you want it and you know exactly how it will fold up.

Hi, what method in solidworks are you using to flat pattern non-uniform shapes ? I'm trying to do an F8F Bearcat , but with the tear drop cross section that also tapers is frustrating me. Any help would be appreciated. Thanks
 
#11
Hi, what method in solidworks are you using to flat pattern non-uniform shapes ? I'm trying to do an F8F Bearcat , but with the tear drop cross section that also tapers is frustrating me. Any help would be appreciated. Thanks
Best way to do that is split the section you are trying to do up into multiple, smaller pieces. Shoot me a PM, I'd be happy to explain in detail if you want to show me an example! Maybe I outta make a full CAD tutorial one of these days! I'll be getting back to my projects in about a month.