Got out this morning and did another material sourcing run. It didn’t go as well as I had hopped, but that’s okay. I have made some solid decisions on materials and can now start buying what I need for the 1:4 scale project, as well as buying materials for the full scale airplane. Full steam ahead!
First and foremost, I’ve been able to source a majority of wood products locally. However, it looks as though I will have to run with one of the regular aviation suppliers for the 1/16″ plywood. I can find 1/4″ and 1/8″ but that’s as thin as local suppliers carry. 1/4″ AA marine is relatively easy to find, 1/8″ is tougher, 1/16″ is nearly impossible in any grade.
I found a local source for aircraft cables of the mechanical control variety; not electrical, which I suppose would be obvious to anyone who has been reading this blog since I don’t plan on installing an electrical system in the airplane. It looks like Orchard Supply carries aircraft cable as a regular item.
A local supplier for composite materials is TAP Plastics. I had a feeling it wouldn’t be particularly difficult getting some of the composite supplies locally. They don’t have all of the right fabrics, but they do have some. I am not sure about the resin and epoxy they stock, but for the basic materials to work with them, well those they have in spades. I will check out the chemical stuff later when I get to a point that I actually need to think about composites.
I am rapidly coming to the conclusion that I will need to manufacture the ply products I need. The lumber is readily available, ply products on the other hand… With the full scale ply sizes being 1/4″, 1/8″, and 1/16″ the 1:4 sizes are 1/16″, 1/32″, and 1/64″ respectively. As I said earlier in this post, it is tough if not impossible to find ply this thin anywhere locally. So, I have resigned myself to the arduous task of manufacturing a replacement material.
At this point I think it will be a laminated paper product. Layers of a a heavy water-color paper should do nicely, maybe a 25 sheet pad. With any luck the end product will be moderately stiff ply-board in the appropriate thicknesses. In 1:4 scale a 4’x8′ sheet of plywood is only 1’x2′ so it shouldn’t be difficult to find the paper stock large enough. I was thinking of using Gorilla Glue as the laminating adhesive mainly because it is very strong and you can use water to thin it for spreading a very thin layer evenly across the surfaces of the laminates. I was hoping to avoid this but ya gotta do, what ya gotta do.
In truth the only composite parts that I would need to build are the engine cowling and the turtle-deck faring which isn’t even a required part, though, I must admit, I am definitely warming up to the idea.
The EAA Chapter 62 meeting I mentioned in the last post got me thinking about composite materials and processes. I haven’t done any fiberglass work in a long time but that is going to change with a day-job project that I recently started. It has some fiberglass work that needs to be done, so I figured I could brush up on those skills and maybe put some of the new techniques into action.
I purchased a book on fiberglass repair and construction to refresh the old gray matter on the subject. It has nothing to do with aviation but it is all about the basic skills for fabrication and repair in the medium. The book was published in 1988 so some things might be a little different or out of date material-wise, but the skills should transfer reasonably well.
Till next time, blue skies and tail winds,