Optimal Angle for Frame Design Project

[Krazer101]

I am building a frame that is supposed to resist the highest possible force in the horizontal direction. I am stuck at determining what is the optimal angle at which to design a member that runs against the applied load. In my project the load applied is in the - x direction and the member i am designing is in the + x and + y direction. The load is being applied by a loading bar and the force will be applied at a height of 4 in. I was just wondering how to pick an optimal angle for my member. I only have 6 in of platform to work with so I need an angle that will make my frame fit on the platform. If anything is unclear, please let me know; I'll try clarifying it.

 

[Mech_Engineer]

Remember this- most materials are around an order of magnitude stronger in tension than in bending. Minimize the bending forces in your frame, and you will maximize its strength.

 

[Krazer101]

When u mean bending force do you mean compression or bending moment?

 

[Krazer101]

I also have another question. When drawing the free body diagram, is it fine if I assume the external load is applied at a joint then some place on a member?

 

[Mech_Engineer]

When u mean bending force do you mean compression or bending moment?

You're right, I meant bending moments.

I also have another question. When drawing the free body diagram, is it fine if I assume the external load is applied at a joint then some place on a member?

It depends on how the force would be applied in real life. It's possible to draw the free-body diagram either way, but remember if a force is being applied to the middle of a member, it will cause a bending moment in the member unless it is oriented parallel to it

 

[Krazer101]

When I'm calculating the bending moment in each member is it just the force times half the length?