Occasionally you need to make a piece of warped foam board straight and usable. For me it is the horizontal and vertical stabilizers, rudders, and elevators. Not so much a problem with fuselages and other parts that have panels that are bent and glued. Those tend to automatically straighten out any warps. So I usually take 2 warped pieces at the same time. Put a couple of strips of foam board under each end, then add some sand bags in the middle. If you get too aggressive with lifting the ends and adding sand bags you will end up putting wrinkles in the paper covering right where the sand bags sit. It normally takes a few to several days for the boards to straighten out. These pictures were taken outside in Chicago on a cold day. The warmth of being inside the house will be a better place to do this.
When building foam board models you can use pins and tape and tape dispensers and glue guns to hold things down while you work on them. But you may want to make a few sand bags. They will come in handy. I use Ziploc sandwich type bags, one inside the other. You can buy sand box sand at places like Home Depot.
If you build foam board models from balsa model plans, occasionally you need to modify the drawings; add doublers, change the LG mount, etc. With a few drawing or drafting tools it is easy to do. I use the cutting mat board along with a T-square and 45˚ triangle to add details to plans before cutting them out to make templates. These will come in handy for the FT Simple Scout project.
The little red pins are used to hold balsa parts together while the glue dries. Or to hold parts in alignment. They can also be used in foam board construction. The vertical stab and rudder are pinned down to make it easier to apply the tape hinge. Hard to do just holding the parts together while applying the tape.
Attractive aircraft in it’s own way, the Aeronca C-1 is from the late 1920’s. It was called the “Flying Bathtub” because the pilot sat directly on the floor of the airplane. Always wanted to build a model of one and thought now might be a good time to come up with a foam board version.
The elevator of the Aeronca has a very narrow connection between the left and right side. If the elevator is being built with balsa and hardwoods there would be no concern about connecting the halves. But foam board does not have the torsional strength of balsa in this application. An exact foam replica from the plan would give a very narrow strip of foam board to connect the halves. So I decided to add a joiner made from 3/16″ x 1/2″ firm balsa. The middle pic shows what that looks like. Next is the need to cut a 45° bevel on the leading edge of the elevator. Normally cutting a bevel in foam board is easy, but with the addition of the balsa joiner the task becomes more challenging. Two possible ways to make a bevel in the balsa. One is to file or sand the bevel in the balsa before gluing it in to the foam board. Another is to use a power tool. I used a Microlux table saw. Just set the fence and make the cut. Comes in very handy.
Currently working on my first foam board scratch build, an Aeronca C-1. Saw this video of a full scale C-3. Thought it would be good to post.
Just started my first scratch build foam board model. Bought plans for an Aeronca C-1 from eBay. Usually when you think of buying model airplane plans you think AMA Plans Service; a very comprehensive assortment. But I found many plans on eBay. Anyway, you get plans, make a copy, cut the drawings out, glue them to poster board to make templates, then trace onto foam board and cut the parts out. Then assemble the model. One way to glue the cutout plans is to use Elmer’s Disappearing Purple School Glue. It is in stick form, like Chapstick. it’s purple to let you see where you are putting it. In a short time the purple disappears. Just started using it but so far it works very well.