Balsa or Bass

[lllazar]

Wow thats a lot thanks Jeff, a few more questions -

How should i break the 1/8 of the blade off? Isnt it sharp

And how do i "set the blade so it only cuts just a hair over HALFWAY through your sheet stock"?

Thanks! I feel like a newbie all over again

[brad123664]

Does anyone know of a good website to purchase known density balsa wood. I found http://www.specializedbalsa.com/ but they are very pricey.

[quizbowl]

brad, is that you? did mr. diers tell you to ask it?

[jander14indoor]

How should i break the 1/8 of the blade off? Isnt it sharp

Carefully? Safety glasses would be good. I use two pair of pliers. Hold blade firmly with one so only 1/4 to 1/2 an inc of tip is exposed. Grab the tip you want to break off with the other. Give the blade a sharp bend like you want to fold it in half. The metal is very hard and brittle, it will break like glass, kind of. If you are unsure about this, or tend to be clumsy, have someone with steady hands, or a teacher do it. Not as scary as it sounds, but yes, the blade is sharp so be careful.

And how do i "set the blade so it only cuts just a hair over HALFWAY through your sheet stock"?

Depends on the stripper you are using. If its a Master Airscrew, the blade is held on the end of the arm by a plate secured by two screws. Get a piece of hard sheet stack half the thickness you are preparing to strip. Loosen those two screws so the blade can be slid around. Set the end stripper on a flat surface, place that half thickness wood under the blade so it slides it up off the surface. Resecure the blade holding screws. May take a time or two to get it just right, this thing is good, but not a real precision piece of equipment. Most other strippers will be set similarly.

Does anyone know of a good website to purchase known density balsa wood. I found http://www.specializedbalsa.com/ but they are very pricey.

Unfortunately, if you want it cheap, you don't get to specify density. On any site. While it doesn't take long to sort through your stock, asking the supplier to do it adds labor someone has to pay for and makes the remaining stock LESS valuable. You can save some money by only specifying ranges of density, but if you want specific densities, the prices go up fast.

Hope that's clear.

Jeff Anderson
Livonia, MI

[old]

Does anyone know of a good website to purchase known density balsa wood. I found http://www.specializedbalsa.com/ but they are very pricey.

Essentially the only thing you get when you pay more for balsa is known density. You are paying for the work involved in weighing and marking the density. Personally I don't see a lot of advantage to getting known density balsa and here is why. 1. You don't really know what density you will need until you test the pieces. 2. The density varies so much even within a single piece that the density figure you are getting is only an average of the densities of the various parts of the board. The one exception to the known density balsa question is when you know you need some very low density balsa. There are a number of companies that sell very low density balsa as a special item. One company calls it contest grade, while others just call it low density or actually specify that it is guaranteed to be below a certain density (usually somewhere in the < 4-6 lb/ft3 area). Buy a few boards of low density balsa, slit it or cut it with a micro saw and then test each piece for weight and strength. The cost per stick will be very low and you will have a much better idea of actual density and strength of the pieces you have.

By the way there are companies that sell balsa to the highly specialized F1A rubber powered plane market. They have balsa as thin as a few thousandths of an inch and of very low and measured density. There is even a company that sells this type of balsa tested for stiffness (Young's modulus), although their measurement is subjective and rough, but the cost is astronomical. Just for fun we bought a couple of pieces of the stuff 5 years ago. The cost was something like $25 for a 1.5" x 18" piece that was 0.024" thick. We never could find a use for it but it sure was fancy.

[lllazar]

Does anyone know of a good website to purchase known density balsa wood. I found http://www.specializedbalsa.com/ but they are very pricey.

Essentially the only thing you get when you pay more for balsa is known density. You are paying for the work involved in weighing and marking the density. Personally I don't see a lot of advantage to getting known density balsa and here is why. 1. You don't really know what density you will need until you test the pieces. 2. The density varies so much even within a single piece that the density figure you are getting is only an average of the densities of the various parts of the board. The one exception to the known density balsa question is when you know you need some very low density balsa. There are a number of companies that sell very low density balsa as a special item. One company calls it contest grade, while others just call it low density or actually specify that it is guaranteed to be below a certain density (usually somewhere in the < 4-6 lb/ft3 area). Buy a few boards of low density balsa, slit it or cut it with a micro saw and then test each piece for weight and strength. The cost per stick will be very low and you will have a much better idea of actual density and strength of the pieces you have.

By the way there are companies that sell balsa to the highly specialized F1A rubber powered plane market. They have balsa as thin as a few thousandths of an inch and of very low and measured density. There is even a company that sells this type of balsa tested for stiffness (Young's modulus), although their measurement is subjective and rough, but the cost is astronomical. Just for fun we bought a couple of pieces of the stuff 5 years ago. The cost was something like $25 for a 1.5" x 18" piece that was 0.024" thick. We never could find a use for it but it sure was fancy.

How do you work with a piece that small...i have trouble sometimes with 1/64 pieces.

[old]

It is actually not particularly difficult to work with very thin balsa. You can cut it with a razor, scissor or paper cutter, just like paper. What we have found however is that very thin and low density balsa (at least the pieces we got) tend to be extremely inconsistent in density and thickness. It seems that the sander that they use to make these very thin pieces, often has enough flex in it that when it hits a harder (denser) section it pushes away from the sanding drum and so it ends up thicker. So what we got in our normal sized (3 - 4" wide boards) very low density 1/64th balsa was sheets that were sort of like a 3D map of the variations of density of the wood used. It was very interesting to look at but not all that useful. So my advice if you really need some very thin balsa is to either get the crazy expensive 18" x 1.5" pieces, or buy full sized sheets of medium density or higher (stay away from very low density in very thin sheets).

[Bubba1960]

Most places I have looked say that balsa works better

[lllazar]

Well it depends on your personal preference Bubba - id suggest trying both for once, and seeing which you prefer. That worked for me.

[iYOA]

basically your question is
if two sticks have the same mass, is the denser one stronger or weaker?