Building the (Old) FLYLINE Great Lakes 2T-1A Kit (22)

Both the upper and lower wings are covered, ready for finishing. It’s time to get started on the fuselage…but…there’s some more stuff I want to be sure you know about. I have included A LOT of information on building model airplanes from kits in the form of stories from my own experiences in my book, “Hey Mister, Will It Fly”, which you can check out by clicking the “books” tab at the top of this page. There is also a tremendous amount of material in one of my other books,”A Gift of Dreams”, that you can find out about by going to http://www.imperfectlyordinary.com/

With that said, let’s get to work on the airplane.

I started with the bottom,or belly, and used one piece of polyspan for the entire length from nose to tail. Here I have bonded the covering to the bottom radius of the firewall, which was previously coated with BalsaRite adhesive. At this point I have not attached any of the covering along the sides.

This is the trailing edge former at the back of the lower wing opening. I have the covering attached around the outside of the former, just as with the firewall.

I pulled the covering tight from the wing opening back to the underside of the tail and ironed it down at the end of the structure with some tension on the polyspan.

The next step is to attach the covering all along the bottom longerons at either side of the fuselage. Notice that I have wrapped the polyspan around to the side face of the longeron to increase the bonding area.

I have cut away the covering across the lower wing opening and attached the edge of the rear belly section to the trailing edge former. The plywood plate with the brass insert is the lower wing attachment structure.

This is the leading edge former seen from the bottom, where the cutout in the front part of the lower wing will join the fuselage. I am sealing the polyspan down tight against the face of the former with plenty of overlap, or "foldover", to ensure a good bond.

This is the polyspan on the bottom rear of the fuselage, folded over the lower longeron and sealed down. The structure at this point is ready for the fuselage sides to be covered.

When I folded the covering around and over the lower longeron I covered up whatever adhesive (BalsaRite) might have been left exposed on the longeron, so I need to add more along both the side and the bottom edge where the covering will wrap/overlap back around the belly.

This is where covering the fuselage gets really interesting. I have cut a sheet of polyspan that extends the entire length of the fuselage from the firewall to the tailpost (fin trailing edge), down around the lower longeron and up far enough to reach the top center of the fuselage and all the way to the top of the vertical fin. The reason for this is to enable a single sheet of polyspan to bridge across the area defined by the top rear stringer, the vertical fin outline, the lower tailpost, and the lower longeron ALL IN ONE PIECE. In doing this it will form the FABRIC FAIRING at the leading edge base of the fin that is so characteristic of many of the airplanes of this period. This part of the covering process requires a bit of effort and patience, but there is no other way to get it right (and this happens to be the same way it’s done on the full scale jobs) . At this point I have attached the covering all along the lower longeron and all the way up the vertical fin trailing edge. Having a horizontal stabilizer that will attach later, as a separate component, makes this part of the job a lot easier.With the stab in place I would have to make a neat cutout around the base to permit the sheet of covering to fit around it and lie flat on the fuselage side.

Remember that I said the sheet of polyspan for this part of the job extends all the way to the nose and all the way up and past the top/center of the fuselage? Here I have begun to stretch and smooth that portion of the covering, with a neat cutout made for the headrest behind the rear cockpit opening. It’s way easier to cover a small protruding part like the headrest with a separate piece of polyspan than to attempt stuffing it into that tight corner without wrinkling. Atia the cat has been in on this project before. There are times when she just does not want to get out of the picture, and this is going to be one of them.

This is the lower wing saddle, or opening in the fuselage, with the side sheet of polyspan attached and wrapped around the edge of the structure.

The right side of the fuselage is covered. You can see how the polyspan is attached all the way around the perimeter of the vertical fin, around the small fairing and all along the top center stringer. It bridges, or spans across, the entire lower portion of the fin and creates a smooth, sweeping contour. At this point we are ready to cover the left side.

This is another look at the technique of bridging the open area we want to become a smooth fairing with a single piece of covering material. The polyspan is attached along the lower longeron, the entire tailpost, and at the very top of the vertical fin.

This is the same sheet of covering at the front end of the fuselage. You can see that I am putting tension on it along the length of the structure prior to sticking it down to the top of the firewall former. I could not get Atia to help me pull on it.

This is the hard part. I have the sheet of polyspan pulled smooth and attached all along the bottom and rear edges of the fuselage structure. Now the trick is to slit it as near as possible to where it will meet the top stringer, the fin leading edge, and that little fairing, and then PULL and STRETCH until the covering lies flat enough to stick down against all those top edges.

This is one of the interplane, or “N” struts. I always cover bare, solid wood structure like this to get a better, lighter finish base than I could achieve with just primer and sanding. In the case of the Great Lakes struts, I chose to use silkspan and clear dope rather than polyspan because I have had so much experience working with those materials in places like this. Each strut assembly will be covered in the same way we’ll do this one. First the entire strut gets a heavy coat of clear nitrate dope, and when that dries, a good sanding to remove as much of the fuzz and bumps as possible. After cutting the requisite strips of silkspan to the right size (a bit oversize) I mist each piece in turn with water (which makes it limp and easy to lay flat without wrinkling), add more clear dope to the strut surface, and press the silkspan into place like this.

Here's one entire strip of silkspan, wet and stuck along one side of the strut with dope

With plenty of dope on the "new" side of the strut I fold the strip of silkspan over tight against the wood and press it firmly into the wet dope.

Here's another look at the process of brushing dope along the surface where the silkspan is going to be attached.

And here's another look at folding the wet silkspan over into the fresh dope. Clear nitrate dope used this way will dry really fast...with a little careful pressing and rubbing you can expect a strip of covering like this one to stick down and stay put within a minute or less. If it pops loose, add a bit more dope in the critical area and try again. This extra work exercise of covering the struts will really pay off in all the work you DON"T have to do to seal the wood grain later on.

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