Scratchbuilding a Model in Card, Step by Step - Page 2

EricGoedkoop · 15 July 2005, 08:01 PM

Once the fuse sides are cut out, I add the internal structure. Not only does this look good when you peep through the cockpit, modelling in card has some distinct advantages when it comes to doing the old birds. First is translucence; on CDL or white models, in strong light you'll be able to see the structure through the skin just like the real thing so it's worth it to put all the framework in there. Secondly, through simple handling as the model is built, the card skin will tend to "suck" in a very little bit between the uprights. Luckily for us, fabric on the originals does the same thing. It's subtle but very effective.

1) This is the template I used to cut out the fuselage sides earlier. I drew the upright locations on it (after arriving at a compromise between Messrs. Stair and Dumas) and then transferred these marks to the top and bottom edges of my fuse sides.

2) One completed fuselage side interior. All the framework is made from strips of brown cardstock 1mm wide. The very fore section is covered with a piece of black cardstock, as this area is panelled in metal on the real aircraft. Diagonal bracing wires are drawn with a .5mm mechanical pencil, after the framework has been glued in.

3) On the exterior of the fuse side, I've marked the fore section panel line. You can also see where I've poked a hole in the side a little further aft - this is an attachment point for the wing bracing wires. It's much easier to mark all this stuff now on a flat piece of card than to try and figure out where it should be later.

EricGoedkoop · 15 July 2005, 08:10 PM

With the exception of fuselage side panels, I draw almost every major component directly onto the cardstock, taped to a pad of graph paper. I like to use 10 squares to the inch - this doesn't correspond at all to the fractional inch or metric* measurements I take as I design and build, but the lines are close enough together to provide a nice square frame of reference. Working with a smaller piece of card on top of a full sheet of this graph paper, it's very simple to lay your ruler across the card and see whether you're true or not. This photo shows a fuselage bottom drawn out on the card:

*My apologies to everyone on both sides of The Pond - the ruler has inch on one side and metric on the other and I just use whichever side the thing I'm measuring lines up against best.

EricGoedkoop · 15 July 2005, 08:24 PM

To determine the length of the bottom, I measure along the lower edge of the side. Since it curves, you need to slowly and carefully "walk" the piece along the ruler. The width of the bottom at front and back can be taken from the three-view drawings, but a bottom cut to the straight length seen in plan view will come up short when you try to wrap it around the curve of the lower fuselage. This is the sort of thing that I believe there are some software packages designed to calculate and draw for you, but what fun is that?

I only do longerons on the sides, not top or bottom. You'll notice two strips of blue low-tack masking tape running down the sides of the piece - this is how I maintain a clean edge to glue the sides to the bottom without any of the framework showing where it shouldn't. If I ran a "longeron" down the bottom as well, the side would sit on top of it and you'd see that single thickness of brown card at the joint - remember that we don't get to cover it up with paint later. The point is somewhat moot on this particular model, since the MoS and Pfalz machines had black reinforcing tape on all the corners and that would hide the brown layer, but the step also helps to align the sides flush to the edge of the bottom so I don't mind taking the extra time. The tape strips are about .5mm wide, which is approximately the thickness of two layers of cardstock (the fuselage side skin and framework). The crosspieces of the frame are simply cut to fit in between the tape, whereas the black panel at the front is an oversize piece of card sprayglued in place and will be carefully trimmed to size.

Again, to mark the framework locations on the bottom I line up the back end against the back end of the side and work my way forward, to be sure that what I do will match up to what I already did. I've also poked holes for the control wires.

Here's a finished bottom and two sides, ready to go:

Ross_Moorhouse · 15 July 2005, 09:09 PM

This is great stuff Eric. I see all sorts of cross overs from your construction methods into the plastic world too. Sorry I haven't gone fully over to the dark side just yet.

I have unstuck the thread. Wouldn't be fair to everyone else that has threads going here.

EricGoedkoop · 17 July 2005, 01:16 PM

Now we're getting somewhere! Sides and bottoms glued up:

All the framework lined up nicely. The bad news is that it seems my "careful" measurement wasn't careful enough:

The bottom of the MoS came up a full 1/32" short. I measured and drew the parts starting at the back end and moving forward, so that's how I assembled them too. If I had lined up the front edges, it would have moved the point at which the fuselage's horizontal taper begins and that would've screwed everything up. I'll have to fill the gap with a strip of card, and since there will be another layer covering this area to represent the metal panel this little glitch shouldn't matter in the end. The bottom of the Pfalz was also a hair shy, but not enough to worry about.

EricGoedkoop · 17 July 2005, 01:33 PM

Next step is the fuse top / turtledeck. Like a lot of the Pioneer and very early-war kites, this one has a flat back. Easy!

1) Top panel, drawn and detailed just like the bottom. The curved front edge of this piece (which forms the back of the cockpit opening) was drawn and cut with the assistance of a circle template. The framework along this edge is a thin strip cut from two layers of the brown card laminated with spray adhesive.

2) Before attaching the top, I added some cross-members in the cockpit. These are three layers thick, and hold the sides parallel and properly spaced.

3) Fuse top glued in place.

I determined - too late - that things were going to work out much nicer at the cockpit if the top of the fuse was fit between the two sides, instead of set on top of them. Had I thought of this earlier, I would have done the framework differently and provided a ledge for the top like I did for the bottom. I didn't, and here's the brown stripe I made such a big deal about avoiding yesterday:

Twice in one day . . . . .

Good thing we're going to have those tapes to cover it up.

EricGoedkoop · 17 July 2005, 01:36 PM

This is a good time to check for square and make sure nothing is too far out of whack. Paper can be "persuaded" to a certain extent, but if you've been careful up to this point the back half of the fuse should be very close to plumb all the way around.

Taz · 17 July 2005, 04:08 PM

Eric- That is just bloody amazing. Have seen a couple of your finished card stock models and they are absolutely beautiful.

Terry Phillips
Taz

EricGoedkoop · 17 July 2005, 06:30 PM

Thank you, Taz.

EricGoedkoop · 17 July 2005, 06:39 PM

Next thing to take care of are the panels on the front end. Bottom first - just an oversized piece of black card with one nice staight edge, lined up to the marks I made on the sides earlier and trimmed flush:

A little tip here about spray adhesive . . .

The only kind I use for permanent bonds is 3M's Super 77. The stuff holds like iron. This is good - except not so much when you're trying to line up one piece on another and there's a good chance it won't be exactly where you want it the first time around. If you spray one surface and immediately bond it to another, you will NEVER move it. If, however, you spray your part and then let it sit for 60 to 90 seconds, the adhesive will tack up a little and you'll be able to reposition the part once or twice after sticking it down, should you need to.