Side gussets are way better than the other options. As the load transfers from one part to the other it really has to do it through the sides, since the top and bottom have discontinuities and there is no stiff path for the load to go. The stress shears out to the sides through the welds into the gusset, then similarly shears back out into the other part.
We'd love to make all gussets perfect, but there are other design constraints like using tabs & slots for alignment and easier manufacturability! Can't really use those with a side gusset. Any tips on a least bad gusset design when you want to use tabs and slots with the gusset?
Can you expound further on your first example of how to transfer the best flow of stress without adding a gusset. I didn't quite grasp how you were welding on that last plate and the orientation it was in. Thanks
The goal of the adding the plates is to distribute the loads/stresses from the horizontal tube to all of the vertical tube. With no plates or gussets, we only interface with the left face of the tube. The lower plate is just like the upper cap plate and will fit inside the tube. The purpose of the plate is to take the compression on the lower half of the horizontal beam and distribute that to the sides and back of the vertical tube.
Interested in how you increase SM without increasing the area moment of inertia...did you post a video that explains this? Also, what would be benefit of this? Thanks.
Generally speaking, SM will increase with AMoI. I believe the desire is to gradually add material so that it will change the stress flow pattern. Adding material at the neutral axis allows for limited stress concentrations and then tapering it to the edge has minimal effect on the existing structure.
When welding the gusset. You would weld all around the exterior. But the interior would you leave that free? I'm thinking welding the interior would change how the stress flows, in way you don't want. Is that correct or would you weld the interior as well?
The general idea is to have gradual transitions. The angle of 22.5° works well in most cases. I will usually start the gusset at the neutral axis and then taper the leg at 22.5° until I get past the edge of the horizontal tube.
Side gussets are way better than the other options. As the load transfers from one part to the other it really has to do it through the sides, since the top and bottom have discontinuities and there is no stiff path for the load to go. The stress shears out to the sides through the welds into the gusset, then similarly shears back out into the other part.
We'd love to make all gussets perfect, but there are other design constraints like using tabs & slots for alignment and easier manufacturability! Can't really use those with a side gusset. Any tips on a least bad gusset design when you want to use tabs and slots with the gusset?
I do have this guide on tab and slots. mentoredengineer.com/warning-on-self-fixturing-parts/ I don't know your application so I can't help too much.
@MentoredEngineer cool I'll check that out thanks!
Can you expound further on your first example of how to transfer the best flow of stress without adding a gusset. I didn't quite grasp how you were welding on that last plate and the orientation it was in. Thanks
The goal of the adding the plates is to distribute the loads/stresses from the horizontal tube to all of the vertical tube. With no plates or gussets, we only interface with the left face of the tube.
The lower plate is just like the upper cap plate and will fit inside the tube. The purpose of the plate is to take the compression on the lower half of the horizontal beam and distribute that to the sides and back of the vertical tube.
Interested in how you increase SM without increasing the area moment of inertia...did you post a video that explains this? Also, what would be benefit of this? Thanks.
Generally speaking, SM will increase with AMoI. I believe the desire is to gradually add material so that it will change the stress flow pattern. Adding material at the neutral axis allows for limited stress concentrations and then tapering it to the edge has minimal effect on the existing structure.
Thank you for the response.
Love this.
How would you do this without a lap weld. Sanitary design?
When welding the gusset. You would weld all around the exterior. But the interior would you leave that free? I'm thinking welding the interior would change how the stress flows, in way you don't want. Is that correct or would you weld the interior as well?
I always weld the inside. There isn't a big difference in the stress. Plus it prevents rust on steel.
thank you sir
is there a set distance that the gusset needs to travel along the horizontal bar to be sufficient enough for support? say on a 20ft long carport roof?
The general idea is to have gradual transitions. The angle of 22.5° works well in most cases. I will usually start the gusset at the neutral axis and then taper the leg at 22.5° until I get past the edge of the horizontal tube.
what are the weldpoints on gusset#3.
You weld that all the way around.
Blahaha lame tip
I did deliver on my promise.
I really appreciated this tip, quite a lot as a hobbyist.