Every now and then I have to repost the following. I don't mean to be preachy, but there are some relatively simple answers to the balsa problem.
Okay, here goes with my take on the balsa situation:
Note: I posted a version of the following a few years ago, but I feel it needs repeating here again. A few sentences have changed from the original post, but the gist of it all is still the same, and I feel critical.
Hi all:
This post will be my attempt to help all of us understand the realities of the current balsa situation and how we can help ourselves immensely from now on into the future to deal with these realities. I’m posting this piece because I believe the need for the following information is critical to model airplane building in the 21st century.
First the medicine:
The days of 4 to 6 pound, clear, straight grain, 3 to 6 inch wide in-one-piece, readily obtainable, inexpensive balsa wood are essentially over and gone. Please read that sentence again. It is essential that all of us face the realities of the situation. Sure, we will occasionally be able to find isolated stashes of Ecuadorian Gold, and we should snap up those opportunities when and where they present themselves. Those of us who have been at this for awhile can remember the amazingly clear and consistent contest grade balsa that we used to be able to get on a regular basis from several suppliers. That type of wood in the quantities in which we used to receive it simply isn’t available anymore.
Where has all the balsa gone? (Sounds like an old Peter, Paul and Mary song…) The real question is, “Where is all the balsa going?” What I’m going relate now may seem incredulous, but I have checked the facts with several people who really know the balsa business and it is apparently true. A few years back most of the balsa was going to the ship building industry to line the holds and hulls in super tankers. Perhaps someone who knows more about that construction will jump in here and elaborate. Today most of the wood that’s imported is going into (and this is so ironic…) making propellers! No, not 12 x 6 inch props and the like, but rather 30 and 40 and 50 and 60 foot diameter wind farm props. The word I get is the manufacturers of those devices are purchasing huge amounts of mill run balsa from which to make the blades for those props. They apparently don’t care too much about the densities of the wood and so are just buying it up wholesale. And with it, virtually all of the “good” stuff as well.
Add to that fact that there just isn’t as much soft, light, straight grain wood coming out of the forests anymore, and you can understand that we are lucky to get what we do get! The above will no doubt cause much debate here, but all the debate in the world will not change the central fact (The 4 to 6 pound Gorilla in the room if you will…) that “our father’s balsa” is not the kind of stuff we are able to get in quantity these days. Nuff medicine?
Now the Honey:
Take great heart, because there is an answer to this problem for us. However, that answer will involve all of us accepting some new paradigms. As most of you know I’m back pretty much full time in the model airplane component business (At least I was when I first wrote this...). As that fact became more known, my business doubled. I’m a happy guy… What has been difficult is getting enough wood in the sizes and densities requested to fulfill my covered foam wing orders. This is not the first time this has happened to me. Back in the late 1960s and all through the 1970s I had a very successful concern that specialized in custom foam wing manufacturing (Control Line Specialties/Control Specialties). At that time I was able to purchase reasonably good quality wood, but even then getting a sufficient amount of 1/16 inch thick, 4 to 6 pound stock was a bear.
The answer was simple: Use thinner wood in heavier densities. I started producing wings covered with .045 (3/64 inch thick) balsa, and even many covered with .032 (1/32 inch thick) balsa. Look at the logic: A piece of 1/32, 10 pound density balsa, in a given length and width, weighs EXACTLY the same as a piece of 5 pound density 1/16 inch thick balsa of the same length and width dimensions. Please read that sentence again…
I’d say that 90 to 95 percent of the wings I produced in the aforementioned era were covered with the .045 material, and that included many, many wings used by the very top competitors in Stunt in the country. The overall result was the ability to keep pace with the incredible number of wing orders and provide strong, light components.
Once my clientele had bought into this concept, they found many other advantages to the shift in the wood paradigm. The heavier density wood had much better grain integrity. A good deal of soft wood contains “wind checks.” Wind checks are chordwise cracks in the balsa sheet caused by the parent tree having swayed in the wind while growing. These cracks typically form across the trunk of a light density wood tree in several areas. This wood is not ideal for model building; especially where we need the strength of uninterrupted grain structure – such as in foam wing skinning.
The heavier density wood has a couple of other advantages: Being denser it will not soak up as much glue during the covering process, nor finishing materials during the finishing process! Soft wood acts just like a sponge! You can also apply a better quality finish over a harder surface than you can over a softer one.
Okay, the facts are that by using the denser balsa in thinner sections we can achieve as light or even lighter wings of a given size that will also accept a lighter, better finish. But the biggest factor is that this type of balsa should be easily available to us through any one of the balsa suppliers on an ongoing basis.
My advice is that when you are ordering custom thickness balsa wood, don’t order just a few sheets of it. Balsa suppliers will gladly adjust their cutting and sanding equipment to supply you with the thicknesses you desire, but meet them half way by ordering enough to make it worth their while to make those adjustments.
The above was accepted technology in the foam wing business back in the 1970s, and I don’t know what happened to change the paradigm back to the use of lighter density, thicker sizes in the interim. The good news is that we can once again use this avenue to have our cake, eat it too, and then all go out for a big desert afterwards.
My wood supplier has informed me that he can supply virtually all the wood I need in thinner, higher density form. That’s the direction I’m heading. I will continue to order and offer 4 to 6 pound 1/16 and/or 3/32 as requested, but the prices will be staggering as this type of wood is at a super premium these days. My prices will, in turn, reflect what I have to pay to get it. Which brings me to the last point I want to make in this post: Major manufacturers do not cater to us in large part because we are unrealistic in our perception of what hobby items should cost. Times have changed, and we must face the facts that the prices we paid for quality merchandise 20 years ago are not the prices we should expect to pay today. This is especially true of the balsa we use. If you think about it, balsa is about the least expensive major component in any Stunt model. If we had to pay double or even triple to get good balsa materials for our projects, it is still a bargain. So a shift in paradigm in our expectations of what we will have to spend to receive satisfaction is also in order. We cannot expect the manufacturers to keep the prices to us low while at the same time they are paying more. That is just an understanding of simple economics.
Yours for a viable modeling future – Bob Hunt
Okay, again, the above was written a few years ago when I was still in the foam wing business. But, the salient facts about thinner, higher density balsa still remain. We need to adjust our thinking. And, we need to also investigate other materials for building our models, as well as new building techniques.
Just my two cents (which is all I have left after buying balsa and gas...) - Bob Hunt
Topic: What balsa for different bits? (Read 1057 times)
