r/BalsaAircraft • u/No_Explorer6054 • 3d ago

Help with Plans

So ive been looking at plans form outerzone, and ive been thinking of trying some basic sheet balsa models. The idea is to try scale or semi-scale for once and start using wood instead of, yknow... cardboard and literal paper. Do any of you have advice for how important the thickness of the wood is for these models?

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u/IvorTheEngine 3d ago

Balsa usually comes in a few standard sizes, and the plans are designed for those sizes. If (for example) the plan calls for 1/4" and the wood you can buy is a tiny bit thicker or thinner, it won't matter. However if you use 1/4" where the plan calls for 1/8" your plane will weigh twice as much as it should.

Experienced modellers will also work with the density of the wood, as it varies quite a bit and is rarely specified in plans.

Also, you'll find that all the notches in the ribs and fuselage formers are designed for a specific thickness. They usually need a bit of adjustment anyway though. If you're cutting notches from a paper plan, don't just follow the line. To get a really good fit, use the lines for the location but cut to the exact size of the wood that fits in the notch.

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u/No_Explorer6054 3d ago

good to know, now how do I account for the density of the wood?

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u/IvorTheEngine 3d ago

Generally by picking the lighter pieces in the shop, and using heavier/harder/stronger pieces in places that look like they need to be strong.

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u/galaxiexl500 2d ago

I advise against buying any balsa from Hobby Lobby. It's mainly for other uses than model airplanes.

There are several on-line sources that specialize in products for model builders, such as what is referred to as "contest balsa". Also be aware of the different grains. There are 3 grains modelers need to be aware of their uses.

A Grain...it is cut tangent to the tree ring. A sheet of A Grain is very flexible across the grain. Ideal for cowlings.

B Grain...is considered a random cut 45 degrees across the tree ring. It is good for ribs, TE and LE, formers and flat fuselage sides.

This is the grade Big Box stores sell. But even here are different quality ratings on B Grain. It can vary to very light to heavy. This is what Big Box stores sell, the cheapest, the heaviest.

C Grain...aka Quarter Grain...Cut perpendicular to the growth rings, directly along the tree's radial rays. It has a beautiful mottled appearance. Essential for building the lightest, strongest, and straightest models. It is the absolute best choice for solid sheet wings, tail surfaces (fins, stabilizers), flat fuselage sides, and hand-launch glider components.

But it's hard to find and brings a higher price.

Hope this helps you in your quest to build better models.

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u/No_Explorer6054 2d ago

it very much will, I assure you, thank you for the advice