I am interrested by the general strategy to modelise your plane. I will try to translate it for sketchup.
(Nb : sorry for my bad english. I try to do my best...)
One thing to check before you get started is the size of the 3-view you're gonna use.
Every time I started to work on the model to continue the tutorial, Rhino and my computer would choke up and freeze. It wasn't until I checked the 3-view and realized it was 8 mb, or 9000px by 9000px that I found the problem. Just loading the background bitmap was eating up all my memory. Once I shrunk it down to a more manageable size (Less than 1 mb), everything works fine now.
Time to design the canopy, which can be both a nightmare and a delight. A well drawn canopy makes the model. But it's the hardest part to get right.
Start of by determining the shape of the canopy. In this case, a simple ellipse.
Select the Ellipse from 2 points tool, and try to outline the canopy.
Next, select the ellipse, and press the project button.
From the top view, click on any sections of fuselage covered by the ellipse, then press enter.
And you get this. We only want the one on top though, so we're gonna kill 2 birds with one stone...
Select all the pieces of the Fuselage, then right click on Layer 1 in the layers window. Select "Change Object Layer"
After that, I usually change the color of the layer to black, for ease of visibility.
Click the lightbulb next to layer one, and the fuselage disappears.
Select the unwanted lines and delete.
This part is tricky. What I do is use a polyline to trace the outline of the canopy trying to balance accuracy of shape, and number of segments.
Then, draw connecting lines across the footprint
Next, draw a line from the middle of the connecting lines to the outline.
Then using an ellipse from center, click on the ends of the connecting line, and the outline.
Repeat for each segment, and hopefully it'll look like this.
Now, to get rid of the extra bits of the ellipses.
Select the footprint ellipse, and press the Trim button.
Click the sections of ellipses below the footprint.
And it should look like this
Now we need to break up the lines into segments. Start by selecting the footprint ellipse. Then press the Split button. Select the profile curves and press enter.
Now it's split. Do the same for all the rest of the ellipses.
Now to draw the parts. Go to Surface> Sweep 2 rails
Click the top line first. The first line picked HAS to be straight for this to work
Then click the bottom line, and the sides
Then press enter. In the dialogue box, Click OK with out making changes.
Rinse and repeat for the rest of the curves.
Now, to save some work for the other side of the canopy, we're gonna mirror.
Type "Mirror" in the command bar, and select all the canopy sections.
From the front view, click in the middle, and move the mouse. You should now have a mirror of the canopy.
This next step isn't necessary, but I do it to save time later. We're gonna merge both sides of the canopy into one piece.
Go to Surface> Surface edit tools> Merge.
Click on two pieces of the canopy that are next to each other.
Repeat for each section.
And the canopy is done.
Hmm. 20 image limit for posts. Now I know. Here's the last shot I wanted for the canopy, showing it on the fuselage.
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I'm gonna put this on hold while I polish of the Rutan Proteus. That'll but the B-45 as the next model, so I can focus on it 100%.
Time to feather this flightless bird (add the wings)
First thing to do is determine the width of the wings (I can't remember the official term for it)
From the top view, draw a line from the leading edge to the trailing edge.
since this 3-view doesn't have a cross section, we're gonna have to wing it (pause for laughter...or crickets)
Use a combination of the curve tool, and polyline tool to kinda make an airfoil shape.
Now we need to match the chord (thickness) of the wing. Select the airfoill shape u just drew, and type in "Stretch" Make sure ortho is on.
click on a spot on the bottom, then a spot straight up on the top and drag until it's as tall as the wing, then let go.
Now click the rotate button, click on the front and back of the airfoil, and rotate the trailing edge down to match the profile of the wing.
Keep the airfoil selected, and press the project button.
Then select the sections of fuselage it overlaps, and press enter.
We're not gonna use these in the design phase, they're the shadow marks for the where the wing goes through the fuselage. It's just easier to draw them now.
Now to draw the wing. Select the airfoil again, and drag it out until the wing changes angle, about halfway through where the engine will be.
And loft it (same procedure as when we did the fuselage). Make sure the seam is at the trailing edge, and control points are set to 50.
Hopefully your wing looks like this
Gonna cover a couple steps in this one.
-Select the airfoil again (It's still at the end of the wing section we just drew), and drag it out to the end of the wing, until it changes angles again. Make sure you move it down to include the wing droop.
-Use the polyline and curve tools to recreate the wing tip.
-Then use the rotate tool to line it up with the center points of the airfoil, and to include the anhedral.
-Highlight the airfoil shape again, and press the split button. Then select the wingtip shape you just drew.
The airfoil should be split into a top and bottom. Type loft, then select the bottom part and the wingtip.
Repeat for the top half of the wing tip.
Then, select both parts of the airfoil and press Ctrl-J to rejoin into one piece.
Now loft the outer wing section.
Make sure to put the wings on their own layer. Makes things less confusing later.
Repeat the wing procedure for the tail feathers.
All done with the wings. It should glide a lot better now.
Time to give this puppy some oomph by adding engines.
The engine nacelle is done almost exactly like the fuselage, with a twist (literally in this case, they angle downwards and inwards)
Use the circle tool to draw to draw the shapes, then drag them into place.
To make the engine and exhaust plates
Go to Surface> Planar Curves
Select the surface edges of the first and last sections
Put it on it's own layer.
Now we're gonna make it fit on the wings. Usually I have engines slide over the wing, but in the case of this model, that wouldn't leave enough engine to be buildable. So, we're gonna cut the wings to butt up against the engine.
Press the trim button and select the engine and press enter.
Then, turn the engine layer off by clicking on the little light bulb by it. and click on the inside edges of the wings. Now u have the wings trimmed to fit the engines.
Now that we've severely weakened the wings by breaking them up, we're gonna need to add internal support. What I do is use the rectangle tool to draw a box over the top of the wings, then project from the top onto the wings.
Then turn off the wing layer to show the lines just projected (there will be ones on the top and bottom. simply loft between the lines to form a box. To make it square, rather than setting to 50 control points when lofting, click on "Do Not Simplify"
Now, we need to mark the fuselage and engines where the wing box will go through them.
Turn the fuselage layer back on.
Go to Curve> Curve from Objects> Intersection, then select the wing box and fuselage sections that intersect.
do the same for the engine, then mirror the engine, wing box and wing so they match on both sides.
Almost done. We just need to draw the landing gear, add panel lines, and unroll everything.
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