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Tab1 in the fuselage layout window shows 12 of the 20 section grids, each with 9 movable control points to model the fuselage section. The other 8 grids are out of sight to the right and you may move back and forth by clicking on the leftmost and rightmost center arrows.

Set the maximum section radius by referring to your scale drawing. Set the fuselage drag coefficient to 0.20, an average number for light aircraft of similar design. Don't overlook this setting as leaving it at zero produces an aircraft that will float forever as you try to slow down. This can be adjusted later, if necessary, to tune performance specs. Body location can be left at 0-0-0.

You must use all 20 grids at spacing you can set in the boxes above each grid. The first and last grids reduce to a single, centerline point produced by clicking on that location in #1 and #20 grids. Set these locations at 0.0 for #1 and the fuselage overall length, measured from the drawing, at #20. Space the remainder with the majority close together in areas of complex curvature; usually the forward third or so, the remainder toward the rear where only a few stations are needed. Make certain you include a grid location that matches each of the section locations on your scale drawing.

These and other dimensions can best be determined from your scale drawing, using a good set of dividers to measure distances on the scale bar, then transferring the figures for the top, bottom and rightmost dimension by moving #1, #5 and #9 control points, and eyeballing the rest to achieve a smooth contour. Don't forget that dimensions on the drawing are usually in feet and inches whereas Plane Maker demands Feet and fractions thereof. Thus, 2'-3" on the drawing becomes 27/12 inches or 2.25' My settings were: 0.0, 0.04, 0.09, 0.26, 0.45, 0.72, 1.02, 1.50, 1.91, 2.19, 2.62, 4.28, 6.30, 7.61, 9.60, 10.81, 13.70, 16.78, 19.30, 19.31 Clicking on Tab2 reveals the top, side and bottom views with the still-to-be-modeled body cylinder having this station spacing.

To aid in setting up this station spacing it is useful to load a background bitmap of the side view (remember the background bitmap we prepared earlier?)

click on the "Load Left Background Bitmap" button at the bottom of Tab2 and navigate to your J3_Cub folder where your Side View bitmap resides. Clicking on the file should produce:

If you don't get a background image that fits the width and length specifications you entered, adjust the radius settings on tab1 or reload the image into Photoshop and vary the width/ length settings until you get a good fit. Photoshop should be running concurrently with Plane Maker so that you can switch back and forth between the two applications with the alt-tab keys. Save your Photoshop alterations each time, replacing the old file, then reloading it in Plane Maker to see the result.

Once you get the desired result, you can adjust the station spacing on Tab1 to get grids that line up with the drawing stations and others that you choose in between.

While we're at it, we can also load a top/bottom bitmap to aid in shaping in the other two windows. I found a good top view, imported it into Photoshop and cropped it to 1016x206 pixels for a good fit. The image is here. Right click on it and save to disk, then import as the top background bitmap. The finished Tab2, ready for shaping should look like this.

At this point, you may proceed to shape the fuselage. What I do, is start with the side view on tab2 and commence moving the control points to approximately match the background bitmap. Since there are 4 control points above the center and four more below, this means scrunching them together with approximately equal spacing between points to get the outermost points, top and bottom to form the profile. All 8 points at each station need to be moved in the side view. Next, move on to the top and bottom views and do the same. These views are symmetrical, so only four control points at each station in each of the views need be moved. Near the front of the fuselage, where stations are very close together, it's often necessary to zoom in closely with the +/- keys to grab the correct control point and still keep them on the station line where they belong. In the screen shot below, preliminary profile modeling of the side and top views are complete, and work has commenced on the bottom view.

Lines in the top view that appear to be trailing off randomly with no control points attached to the ends are actually unmoved control points in the bottom view, as can be seen if you look carefully.

Once this initial modeling is complete, begin moving back and forth between tab2 and tab1, where the section profiles reflect your work thus far. control points 1,5 and 9 are very close to where they belong and you can now move the others which are obviously not, to form a smooth curve.

In the screen shot above, control points in the first 5 grids have been adjusted and the remainder have many that are misaligned. By patiently moving between tabs, the fuselage will get closer and closer to the desired shape. Eventually, tab 2 will look similar to the screen shot below, in which top and bottom bitmaps have been removed for clarity.

At this point, I begin checking section measurements from the drawing against the appropriate grid to ensure that they agree. Some movement of control points will be necessary and will mean more back and forth checking for smooth fairing of all the curves. Tab 3 now becomes very useful, since front and back views of the sections are superimposed and you can quickly tell which of them need adjustment to remove lumps and hollows. Judicious use of the F1 key is also available. This is noted on the "Special" menu as "ellipse-smooth fuselage". It's intended to automate fairing of fuselage lines but the algorithm can easily decide to smooth out-of-fair sections that are design features, rather errors. I use it very sparingly.

Once satisfied with your modeling to this point, you may have a look at the solid 3D view that you have achieved, by quitting out of the Fuselage window. Your model will be displayed without texturing like this.

This gives some idea of what your fuselage looks like, but a better idea can be had if basic textures are added. This is accomplished by going to the "special" menu and selecting the "output texture-map starting points" option. Selecting this brings up a self-explanatory information window. Clicking on "understood" (even if you don't!) will do the job and you may then select, from the same menu, the "reload textures" option. This will result in your model displaying a much more informative picture with station lines and longitudinal members visible as in the screen shot below.

Roll and rotate the model using the w/s and a/d keys. All possible movement of the model in this window is listed on the "background" menu, together with the corresponding keystrokes needed to achieve them.

Bumps, hollows and out-of-fair unevenness can be detected by examining the model in this window, then returning to the fuselage window for touch-up work. As you make changes, the texture-map starting point files will eventually have to be updated. Do this by deleting the current "J3Cub_paint.bmp" and "J3Cub_paint2.bmp" files in your Cub_J3 folder, re-outputting the texture-map starting points and reloading the new textures. Do this as many times as necessary until fuselage modeling is complete. Once it is, we may move on to adding the wings and empennage.