Hi, MadCow,Hi,
I am ordering balsa wood soon, but I am not sure which densities of balsa I should get. I know Balsa Man said some things about wood density, but I was a little overwhelmed at the amount of information in one of the posts (The math is too complicated for me at this point, but I will try to figure it out). I know I will be using 1/8s, 3/32, 1/16, and possibly 5/32. Any recommendations on Balsa Wood densities?
Thanks,
MadCow2357
Rather than specifying exact densities (and spending as much as double what random densities cost), I'd suggest using the same budget and buying double the amount of wood, then carefully sorting what you have by mass, matching the higher density columns to fewer X braces, and the lighter density columns to more X braces. The key to this competition to find the magical ratio that will provide the highest possible efficiency. This can't be done if ordering just certain densities.Hi,
I am ordering balsa wood soon, but I am not sure which densities of balsa I should get. I know Balsa Man said some things about wood density, but I was a little overwhelmed at the amount of information in one of the posts (The math is too complicated for me at this point, but I will try to figure it out). I know I will be using 1/8s, 3/32, 1/16, and possibly 5/32. Any recommendations on Balsa Wood densities?
Thanks,
MadCow2357
I’m very reluctant to say someone who has (successfully) been coaching the ‘balsa building events’ for many years may be wrong on something. We each have developed our understandings, and ways/techniques that ‘work.’ Dan and I are…. ‘on the same page’ on so many things. I know very well I don’t know ‘everything’, and, like all of us, can certainly be wrong at times.Rather than specifying exact densities (and spending as much as double what random densities cost), I'd suggest using the same budget and buying double the amount of wood, then carefully sorting what you have by mass, matching the higher density columns to fewer X braces, and the lighter density columns to more X braces. The key to this competition to find the magical ratio that will provide the highest possible efficiency. This can't be done if ordering just certain densities.Hi,
I am ordering balsa wood soon, but I am not sure which densities of balsa I should get. I know Balsa Man said some things about wood density, but I was a little overwhelmed at the amount of information in one of the posts (The math is too complicated for me at this point, but I will try to figure it out). I know I will be using 1/8s, 3/32, 1/16, and possibly 5/32. Any recommendations on Balsa Wood densities?
Thanks,
MadCow2357
Again, 2 different schools of thought... nothing wrong with that.
Another area where Len and I look at differently...
When we receive a shipment of column material, the first thing we do is to cut them from 36" lengths to 12" lengths. Then we separate by weight (to the nearest tenth of a gram), then further stratify by separating the individual weight piles by bending strength. We have all noticed how, if stripping your X braces from sheets, the weight can vary wildly from one side of the sheet to the other. The same holds true in bending strength. Testing a 36" long stick for bending strength assumes that the stick has those same properties throughout its length. In reality, the stick is more like a chain, and can bow at its weakest area, or more accurately, the weakest area can precipitate a bow in the middle of the stick. Also, if you were to take a 36" stick and cut it into (3) equal 12" lengths, it is unlikely that all 3 pieces will weigh exactly the same. With different weights will likely come different bending strengths. By blocking your potential columns into individual 12" lengths, you can analyze each column independently, without the influence of adjacent pieces in a 36" stick.
The downside to this might be that most super sensitive scales that can weight to .01 grams have a limit of 500 grams. This can be an issue on some 12" sticks in the .5 gram weight and up, as the BS may exceed the limits of the scale.
No, but glad to explain the basic idea, and provide general directions. It is for stopping the load block from being able to drop if/as the tower fails under load. You want the load block to only be able to drop far enough for first failure mode to happen- somewhere between maybe 1/16” and 1/8” By the time the tower has deformed enough to be 1/8” shorter than it started, multiple things will almost certainly have failed. In a 'well constructed'/symmetrical tower may be enough. The cage needs to be plenty strong to carry 15kg load.Do you have any images of the 'safety cage'? I'm trying to construct one, it'd be really helpful to have some examples.
PM me your email address and I'll send you some pics of our cage.Do you have any images of the 'safety cage'? I'm trying to construct one, it'd be really helpful to have some examples.
Users browsing this forum: No registered users and 1 guest