Every builder has made a mistake while building that is very embarrassing, or at least is would be embarrassing if anybody else ever found out about it
. In my opinion one of the most embarrassing mistakes that I have ever made is build two of the same sides of a fuselage. It may sound like this would be hard or impossible to do, but in reality it's very simple to do. And it's a mistake that quite a few modelers have made over the years. And what makes this mistake even worse is there is absolutely no way to quickly recover from this mistake. You have stop what you are doing and call the kit manufacturer and order the replacement fuselage parts you need to correct your mistake. This is usually a 1 to 2 week setback in your kit building
So now I take steps to make sure that I don't ever make this mistake again. The way this mistake is made is by building only one side of the fuselage at a time. There are two pointers that I can give that will ensure that you NEVER build 2 of the same side of a fuselage. First, lay out both sides of the fuselage and make sure they are mirrored from each other. Second, LABEL both sides of the fuselage, LEFT and RIGHT. Make sure that you will always be able to read your labels as you build. Refer to picture #1 and you will see that I have laid out my fuselage sides and that I have labeled them as left and right sides. Now that you have these done, build both sides of the fuselage at the same time. This way you will ensure that you are building correctly, and you won't have any surprises later on.
In our LT-40 kit the fuselage sides are not one complete piece. Because of this our first step is to glue on nose section to each fuselage side. This is a pretty easy step, but you will want to take some extra measures to ensure that the two parts are flat when your glue dries. In pictures #2 and #3 you can see how I used my magnets to secure the parts while the glue dried. You can use what you have on hand to do this if you don't have a magnetic building system. Just make sure that you can put enough pressure on both parts so that the gap between the 2 parts is wood-to-wood contact. If there is any gap in this joint it will wind up being a weak joint, so take your time here and make sure you have it correct.
After we have the nose pieces glued onto our fuselage sides we're ready to glue on our fuselage doubler. This is an important part to get correctly placed because the doubler will position all the parts of the fuselage as you assemble it. If the doubler is incorrectly installed then your fuselage will be crooked. So take some time to study the plans and make sure you know where the parts will be lined up. In my kit there was some difference between the instructions and the actual kit. In the instructions they show to glue the fuselage side and the fuselage doubler together and then to drill the holes for the wing mounting dowels. But in my kit the holes were already drilled in the fuselage. This was a pleasant surprise because these holes will make excellent alignment marks when gluing these two parts together. Before I assembled the parts I did reference the plane with the parts to make sure that everything did line up correctly using these holes as guides. Since they did line up correctly I was ready to assemble the two fuselage sides. Start by laying the fuselage side and the doubler out beside each other, with the parts mirrored (picture #4). Apply glue to the fuselage doubler (picture #5), making sure that you get apply glue to all parts of the doubler. You will want to make sure that you get glue along all of the edges of the doubler so that you will get a good glue bond. If you are using CA to assemble your plane this is a place were you DO NOT want to use thin CA. Both of these parts are made from light ply and the thin CA just will not penetrate these woods, and this will give you a very weak joint. For this application I recommend that you use thick CA as this will give you a good bond and it will give you enough working time to get the glue applied to the part and put the two parts together before the glue sets. Once you have the glue applied to the doubler “flip” it over into position on the fuselage side. I found that the plastic handle of two of my hobby knives fit the dowel holes perfectly so I used these to align my two parts. I wouldn't recommend using the actual dowels to align the parts because if your glue sets while you are aligning the parts you will be “stuck” with the dowels glued in incorrectly and then you'll have a mess to “undo”. I used my hobby knives because the handles are made out of plastic and even if the glue had set while I was working it would have a weak bond with the knife that I could easily take out. In pictures #6 and #7 you can see how I used the hobby knife to align my two parts, and pictures #8 and #9 show the parts aligned at the holes after I removed the knives. While glue it drying you will need to make sure that the fuselage sides are completely flat, otherwise your fuselage will have a warp built into it. The best way to keep your sides flat is to weight it all down so that it is laying flat on your building surface. Use whatever you need to do weight it down, as you can see in picture #10 I had to get “creative” with the weights I used.
Picture #11 shows that I used my weight bags for the other fuselage side. Once the glue has dried you can then remove your sides from the building table.
Pictures
1. Lay our both sides and label them to ensure you build a left and a right side.
2. Attaching the nose pieces to the fuselage sides.
3. Make sure there is no gap between the parts when you glue them together.
4. Preparing to glue the fuselage doubler to the fuselage side.
5. Applying glue to the fuselage doubler
6. Using the dowel holes to align the fuselage side and the fuselage doubler.
7. Using the dowel holes to align the fuselage side and the fuselage doubler.
8. Make sure that the holes are aligned before proceeding
9. Make sure that the holes are aligned before proceeding
10. Weighting down the fuselage sides while the glue dries.
11. Weighting down the fuselage sides while the glue dries.
Until next time
Ken