I too am a little slow on the up take. So for the third time, I am going to go over a VERY important aspect of floor replacement. I hope some of you will learn a very important lesson from this little tutorial. You may be a do it youselfer or you might just want to know how it is done.
DO THIS BEFORE RIPPING OUT THE FLOOR OR REMOVING ANYTHING BEYOND THE INNER SKINS. YOU WANT TO GET THIS RIGHT BEFORE THINGS START TO MOVE.
Very frequently the rear of an Airstream is totally rotted out. The original floor is not going to allow for a proper reproduction of the outside curve. Even if the sub floor is solid, it is not going to give you the proper location of where the C channel is actually supposed to go when put back. The curve was cut by a guy(usually a lower paid, apprentice type guy) with a jig saw. It is not perfect under the channel, it varies. If you guess or extrapolate what the curve is you will probably get it wrong. If you follow my system, you will always put it back EXACTLY where it is supposed to be. The shell will go right back where it was. The holes will all line back up and you will be a very happy camper. If you change the position of the channel when you put it back, you will drastically change the shape of the curve without intending to do so.
What I do, is make a template of the inside edge of the C channel. The C channel always goes back right against the template.
I cut 6" rips of 1/4" luan plywood. DO NOT USE CARDBOARD. It is too flimsy and will expand and contract dramatically with the weather. Luan is cheap and will remain very rigid. I take the rips and cut them up to the needed segments. Each segment is scribed to the C channel. I mark it, then cut it with a jig saw to the line. I then scribe it again, then sand to the line with a belt sander. I have scribed for many years so it usually takes me just two tries of the belt sander, but if it is not correct, I just sand more off till it is a perfect fit.
The scribed pieces are then glued together using hot melt. I then screw it together to allow the glue to set. Wood glue could also be used. A tip; Screw the rips down to the floor as you go. You are replacing the floor any how. Now with my template, I can make my actual piece of the flooring.
AT THIS POINT YOU CAN START REMOVING ELEVATOR BOLTS AND PROCEED TO DROP THE BELLY PAN.
I cut a block of wood 1 3/8" wide to simulate the C channel minus 1/8" for clearance. I use that block to trace around the outside of the template.
This will give you a perfect reproduction of what was originally there. Another tip; mark all the joints between the channel on the template. When putting the channel back down, the template will then aid you in putting all back in order.
I am sure I will get numerous questions on this topic. Please feel free to ask and I will do my best to answer them.