Join Date: Apr 2006
Thanked 161 Times in 158 Posts
Rep Power: 12
Robert, I also like bolts because they are prone to visual inspection. However...a properly glued joint is a fusion joint, and like metal welding it is as strong or stronger than the materials being joined.
A proper "bolted" joint is better seen as a perforated line in the materials, secured by dozens of point-stress concentrations, all there to help the materials fail.
A glued-plus-bolted joint is no stronger than a proper glued joint--but will be WAY more expensive, which means some other corner will be cut or the price will be steeper. And, the joint no stronger. If anything, perhaps weaker because of the point stresses perforating the materials.
In the real world, yeah, I agree with you that there are many poorly glued joints. 30 years ago the folks at Permatex or Loctite (I keep confusing the two, shame on me) actually ran an Indy car with the engine assembled just with their "goo" instead of gaskets and seals, in order to prove the materials worked. They'd experienced large failures when the materials were used in shops, and wanted to *prove* that the problem was sloppy mechanics who wouldn't read or follow the basic instructions, like "clean surfaces before applying".
Glue joints, like FRP hulls with osmotic blisters, depend on the workers to make them properly. Or, not.
And if those same workers torque the hundred plus bolts improperly, the bolts fail and the hull between them is destroyed as well. Same old same old.
Isn't it ever?