We thought we’d leave Sunday afternoon to return to Grantsboro, but in the end, with all that we had to do before we could leave, we ended up leaving early Monday morning. Driving straight through, we arrived just before 8am, and within 20 seconds of Robby. Pretty good timing.
I didn’t mention that the previous week we had a bit of excitement. I had to run to the hardware store to grab some supplies. When I went to leave, I met a volunteer fireman who had the road blocked. He told me that I had to turn around and go the other way. Complying, I turned around and headed back down the two lane road, past the hanger, and then into another road block. I asked if I left, would I be allowed to come back through the road block to get back home. There was much confusion over this question, but eventually, after much debate I received the official verdict.
I went to the hardware store but told Robby via text that I may not make it back. Driving through the back country to circle around, I found every road blocked and volunteer fireman and even younger kids blocking roads. Whatever it was, they were serious. Eventually I made my way back in through the road block and work resumed.
We really didn’t know what happened till the next day when a neighbor stopped by and told us there had been a murder. This was maybe 1/4 mile from where the hanger was. When we had lunch this week, I saw this in the local paper.
Apparently she’d had enough of the old guy. Word was she was a bit different anyway, but who knows. It is not like we haven’t dealt with dead bodies before. Anyway, mystery solved, we went to work.
One of my first tasks was to bend the elevator push rod. That is the black rod you see in the above picture. It is what controls the up and down of the airplane, as in pull back = houses get smaller. Push forward = houses get bigger. It is a major control. Bending a control rod may seem like a bad idea, but all we are doing is introducing a few degrees of custom bend into the push rod so it doesn’t rub and runs true. It is actually difficult to see the bend in the pictures.
If these bends aren’t put in there, the push rod still works just fine. The problem is it rubs ever so slightly on the baggage floor. No sense rubbing the paint off or introducing extra friction into what you hope is a smooth control surface run.
With the controls running free, and some clean up of tools, rivets, trash, etc completed, it was time to start learning how to cover.
All the fabric for the entire airplane comes in one roll. It really isn’t that heavy, but once all the glue is applied, then the primer, paint, another coat of paint, decals, etc, this ends up being a significant portion of the overall weight of the airplane. It is also a large part of the structure, very similar to how the skin is our largest and most important organ. The fabric is very important to the airplane.
The glue that is used is pretty amazing. You mix it with acetone to thin it to the desired consistency. Then you brush it on in relatively thin coats. Above you see a grey part and on the tube closest to the camera you see it barely tinted green. This is after a couple of coats.
Now you see the glue applied at a correct consistency. It is technical, tedious, and demanding. It is also color coded and basically arts and crafts. Glue till it is green enough, then move on. And the materials, while important, are not individually that expensive. If you mess up, get some more and do it again.
But as I was saying, the glue. You paint on a bit of this glue and work around the part in a circle. When you get back to where you started, the glue has already dried so you can keep right on going. Once it is thick enough, you trim some fabric material as you see here. This part is exacting not because you’ll crash if it is wrong, but because you want it to look good. Straight lines, clean cuts, etc. You put a bit of glue on the fabric, then start folding it over the glued up parts. Now remember, the glue has already dried, it actually dries in seconds. So how does it stick?
When you fold over the fabric, you apply a bit more thinned glue that soaks through the fabric. This is where the magic happens. The glue is thinned so much it is basically just acetone. Acetone reactivates the glue, through the fabric. It immediately becomes sticky again and then you adhere the fabric to the now sticky glue. Give it 15 seconds, and it is dry again. Don’t like it? Peel it off, reapply and do it again.
What is your work time for this glue? How long will the glue reactivate with acetone? Robby was at the stage in the picture above one time, stopped working on the plane and went to Alaska for the summer, came home, and went straight back to work. The glue sat patiently waiting and only needed a bit of acetone to reactivate.
So you use the cool glue to basically wrap your part like a Christmas present. Trim the corners, make the folds, get the lines straight, etc. With everything wrapped, and glued you end up with a part that looks sorta decent, but has floppy fabric sorta hanging loose. That is when you introduce the best part, the iron.
You see, the fabric material shrinks with heat. You have three settings on your iron for three different passes you make shrinking the material, but no pass is as fun as the first one. At this point, you’ve been working for half of a day on one part, like what is pictured above. When you pass that iron over the big sections, the fabric draws drumhead tight almost instantly, and you can finally see what all the work was for. You also iron out wrinkles, bubbles, etc so there is some fussiness at this point too. The amazing glue also reactivates with heat so if you have an area giving you trouble, you give it a bit of extra heat and work it out to look perfect.
It takes about one full day to cover a part like one of the ones you see us working on. That is one person, one day, after you know what you are doing. At the stage above, we are only about 1/2 done with covering. We still need to put on the tapes that protect wear areas, the edges, etc. Then later we’ll have to cut access holes for inspections, but mostly they are in the wing and the fuselage. You start with the tail feathers, the pieces that we were working on. Eventually you move to the fuselage, the main body of the airplane. I’m told the tail feathers take longer than the fuselage. If that is the case, we’ll go from naked metal frame to covered airplane in a day. That will be an epic day. But we’ll hold off on that for some time because once the fabric is applied, it gets much harder to get access to all the parts we are working on.
The pieces we are covering here are the blue surfaces on the back of this airplane.
And here you can see the fabric and how it covers the fuselage. The airplane is basically a big steel 4130 box frame, wrapped in a tight covering and painted. It is fragile to being poked, but very strong in the air.
In case you are wondering if this flimsy construction style is strong enough, or safe enough. The control surfaces of World War II aircraft were built the same way. They seemed to be strong enough to do the job.