Why Do I Like Basswood So Much?

Basswood has some advantages over Balsa wood. For instance:

• Basswood has significant natural strength. This makes it easier to work with.
• Basswood bends easily. For making arch bridges, this comes in handy.
• Basswood looks nice
• Basswood is relatively consistent from tree to tree in density.

However, Basswood does have some disadvantages. These include:

• Basswood is more expensive than other woods, such as Balsa.
• Basswood is not always readily available.

Basswood Information
Here is another resource about Basswood.

Glue for Basswood

Basswood does not require the use of special glue. I would still follow my recommendations at my Glue Tips page.

Where to Buy Basswood

I would always recommend that you go to a local hobby store to pick up your Basswood. However, if that is not an option, here are some places to buy Basswood online:
Basswood Sheets

Basswood Sticks

I have a pot, or basin rather, that is about 18″ long and 12″ deep. I fill it with about two cups of water (I have found that more water just takes longer to start boiling, and I usually don’t boil all of it anyway) and stick it on a stove burner. Currently I am using a stove that has a glass top and the burners are underneath, but in the past I have used one that had burners above the top of the stove.

I place any wood I am steaming on top of the basin, I usually have at least one or two pieces that are longer then the basin and some that are shorter, but the shorter ones lay on the longer pieces so that nothing is actually touching the water at this time, for the goal was to steam and not soak the wood. I turn the burner on high, and wait for the water to start boiling. I also place a shallow cookie sheet on top, to hold in the steam.

I have never steamed my wood for over a half hour, perhaps I am too impatient. But with this amount of time the wood is very bendable.

Beforehand, I have prepared two “molds” that consist of two sheets of wood, with a form of nails hammered into each, to mold the steamed wood. I have taken to making the mold a half inch or so taller then what I want the actual height of my arch, because the wood always bends a little less then the form afterward. You may want to use more or less extra height depending on the overall height of your arch.

This form is fairly easy to make, I just set the height and length of what I want with nails, and then bend a stick of wood (usually 1/16″ by 3/16″) and hold it in place by clamping the wood to the nails with clothespins. I then add as many additional nails to the form as I see fit, along the arch of the wood.

After steaming the wood I clamp the pieces to the form and wait another thirty minutes to an hour for it to dry. Again I may be impatient, but it works for me. I then apply glue to the wood, and wait 4-5 hours for it to set (that is the amount of time my glue takes to set). I then do a little sanding, and finish building my bridge. So far, I have built an 8.5 gram bridge (as of Jan/19/04) that held 16k and broke. However, the testing apparatus was not ideal, in the fact that I forgot to bring an S hook to the place I was testing, and had to make do with something else, which I believe may have unevenly applied the load to my bridge. But then again, that may not have been the case.

I usually make my arches into the shape of an L beam, but have used a T beam in the past. I have never used an I beam, though that would most definitely be stronger but heavier. It is worth experimenting with.

Balsa is cheaper and more available than basswood. This means you can buy more wood, and build more bridges for the same amount of money. By building more, you will gain valuable experience and improve your skills. When it is all said and done, you may be able to build a better balsa bridge.

Balsa is stiff, while basswood will bend.That’s right, you can bend basswood more than balsa. That is good if you are building an arch bridge. But what if you don’t want your bridge to bend? Balsa will give you a stiffer piece than basswood for the same size. However, I have seen balsa bend a lot under heavy load without breaking. I am not sure why it was able to bend so much, but it did.

You can get more cross-section for the same mass with balsa. In other words, you can have a bigger piece of balsa for the same weight of basswood. In compression members, larger and lighter pieces will actually hold more than smaller, heavier ones.

Basswood won’t rip off at the joints as much as balsa. Sometimes the face grain of balsa will tear away at the joint. Basically, basswood holds itself together better than balsa.

Balsa comes in a wide range of densities. You don’t always know how strong the wood is that you are getting. Basswood usually comes in a much smaller range, which means you can be more consistent with basswood. That problem can be fixed if you weigh each piece of wood before gluing it to the bridge. That way, you know exactly what is going on your bridge and can keep accurate records.

Balsa is less likely to be the same strength throughout its entire length. If you buy a piece 24 inches long, it may be stronger at one end then the other. This just complicates things, making it harder for you. Basswood is usually uniform in strength.

Balsa will sand easier, but basswood won’t crush.You can squeeze a piece of balsa, and totally deform it. A “squeezed” piece of balsa is weaker, because the internal atomic structure is messed up. You need to be more careful when working with balsa.

Balsa changes weight with changes in humidity more than basswood. Many times I have had a balsa bridge lose weight after setting it in the sun for a couple of hours. Of course, the opposite is true. Balsa bridges will gain weight after humid days. Basswood does not change so much with the weather.

For the same mass, basswood pieces must be smaller. Usually, this means that a basswood joint will have less surface area for glue than a balsa joint. That means you may have to use stronger glue with bass, which might add weight.

So you see, there are many factors that play into which wood is better. Basswood may be better in some places, and balsa in others. I encourage you to experiment with both woods. Specialized Balsa is the company I recommend for buying balsa.

Don’t forget about the other woods.

Birch, Spruce, Aspen, Pine, and others are all alternatives to balsa and basswood. But I guarantee that you won’t be able to find them like you can balsa. They will cost more money. But don’t immediately rule them out, you may want to play around with them, and check out their qualities. Let me know what you find out.

Resources

1. Interesting Facts About Balsa
2. Balsa Wood