In an upcoming project I am going to start with a foam board model from Flite Test, then cut part of the fuselage off and replace the missing part with balsa sticks. Gluing balsa is different from gluing foam board, so I decided to review some basic balsa building techniques for the benefit of those who are unfamiliar with the process. Here is the setup that I use when building balsa models. In this picture the bottom is a balsa building board. Balsa building boards are difficult to find these days. Someone told me that an acoustic ceiling tile will work. There are occasionally single tiles available from a damaged package at your local home improvement store. Next layer is the plan sheet. On top is a piece of wax paper to prevent the wood glue from sticking to the plans. I usually use thumb tacks to hold the plans down and building pins, or straight pins, to hold the balsa in place while the glue dries. T-pins are still available from several suppliers, including Tower Hobbies.
My next project involves gluing balsa sticks to foam board. Since I want to make sure that I get a good glue joint I decided to do a test with the glues that I have available. Four glues to glue balsa sticks to pieces of foam board. Care to guess the winner? ALL of them! I was amazed. They all seemed to work very well. I went with Elmer’s. Been using it since 2nd grade and it never let me down.
If you have one of those nice soldering stands with the magnifying glass and alligator clips, but can’t find it, here is a work around. Take a couple clothespins and hot glue them to something heavy, like a paving brick.
The Flite Test Old Speedster has a plain white poster board windscreen. I used a few Pitt Brush Pens to give it more appeal. Here is the link to the pens on Amazon. When you trace the windscreen on poster board add the gluing tabs on the bottom. The Pitt Pens use India Ink, which is waterproof, but the poster board is not, so you’ll need to spray some sealer on it.
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.
As I mentioned in an earlier post, I am not good and cutting the bevel in control surfaces free hand. So I use a table saw. I have another post coming soon to further explain that process. And then I use Kraft tape as the hinge. The problem comes when you try to put the tape on the two parts properly centered. A classic case of needing three hands. To solve the problem I just use balsa pins to hold the two parts together while I apply the tape. Works great.
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.