Modeling to Cross Sections

[Milton Shupe]

I would like to start a discussion on cross section modeling with the objectives as stated below:

1) Identify best methods of modeling using cross sections;
2) Improve on the processes to expedite this basic and fundamental task of getting the fuselage shaped perfectly.

My method, which is crude but effective, is to simply:

1) create a planar, map it and apply the cross section drawing (I use Fit to Bmp to avoid stretching-then I scale it to proper size), then
2) clone the original planar mapped for each cross section and name per the cross section position;
3) position each planar at the appropriate longitudinal position on the side view aligning the drawing properly on the cross hairs center-line and vertically;
4) create a 18-24 sided cylinder, deleting all but the front poly then change its properties to "See through";
5) clone and position each poly just in front of its respective cross section naming each by the cross section letter.

Now I have all the cross section polys ready to shape to the drawing.

6) Once all are reshaped, I delete all the cross section poly faces leaving only the vertices.
7) Then I begin connecting the cross sections but hand building polys from cross section to cross section.

This is a cumbersome process (takes 1-2 hours for each phase) but gets all the cross sections and fuselage shape done perfectly IMO.

Let's discuss alternative ways to do this and maybe help those of us who model, or would like to start modeling, become more productive and effective at what we do.

I attach an example 1/48 scale drawing cross section view of the Fiat G55. I have larger versions of the full set if anyone is interested.

[Milton Shupe]

Attached are screen shots of various stages in the process. EDIT: This is an example of my start on the CANT Z1007.

Applying the 3-view using "Fit to Bmp"
Completing the cross section planars
Shaping a poly to the cross section
Finished base fuselage

Creating/cloning all the planars and positioning them is fast, just a few minutes.

It takes maybe an hour to adjust vertices to fit the planars.

It takes maybe an hour then to construct the polys to connect the cross sections.

[Ivan]

Hi Milton,

I can't quite see how the finished base fuselage resembles a Fiat G55.
Is that the right model?

Thanks.
- Ivan.

[Milton Shupe]

Hi Milton,

I can't quite see how the finished base fuselage resembles a Fiat G55.
Is that the right model?

Thanks.
- Ivan.

LOL No. The Z1007 is the most recent example of what I have done here so I used the gmax screens for graphics examples.

The G55 simply had a good cross section set that I used to introduce the thread.

[Allen]

I use a 16-12 sided cylinder (CFS2 builder) with a load of Height Segments.

Convert the cylinder to a Editable Mesh and Use Vertex mode with Select and Uniform Scale and Select and Non Uniform Scale to shape the first segment. (I work nose to tail and root to tip). Than I select all of the other segments Vertex mode and move down to the next segment to shape.

[Ivan]

Hi Milton,

Here is a VERY similar model I built a while back. (Still stuck in my paint shop.)

While it isn't sposta be a Fiat G55, with a proper paint job, I don't think most folks would be able to tell the difference without some measurements of exact dimensions. It is amazing how similar the Italian fighters looked to each other.

- Ivan.