HumanPoweredDesigner
Well-Known Member
I built a tower out of wood, with 4 compression caps and truss webbing between them, held together by wood glue. Small gussets.
The caps were small, and I put lots of weight on it until it failed.
Then I examined the wreckage to see why it failed.
Most of the diagonal web members had sheared right off, on both ends, and were laying away from the wreckage. They were not broken. Just cleanly sheared off on both ends.
I think what happened is the compression caps compressed under the weight, but the bond between the web and the caps was too rigid to compress with it, and sheared off instead. I used Elmer's wood glue.
Do you guys think I should have used a different type of glue, or would something else have kept the bond?
I don't think they were pulled off, since they came off on both ends. I think the glue was too rigid to stick to the compressing caps. But I'm not sure.
The caps were small, and I put lots of weight on it until it failed.
Then I examined the wreckage to see why it failed.
Most of the diagonal web members had sheared right off, on both ends, and were laying away from the wreckage. They were not broken. Just cleanly sheared off on both ends.
I think what happened is the compression caps compressed under the weight, but the bond between the web and the caps was too rigid to compress with it, and sheared off instead. I used Elmer's wood glue.
Do you guys think I should have used a different type of glue, or would something else have kept the bond?
I don't think they were pulled off, since they came off on both ends. I think the glue was too rigid to stick to the compressing caps. But I'm not sure.
