I just found a simple and effective way to check your arrows for bends and bumps, even in the field with broadhead or fieldtip.
all you do is find a magnet with a flat surface off about 1" 1/2 hold it with your fingers and place the tip of the arrow under it and let it hang ( you need a strong enough magnet ! )
You can spin the arrow under the magnet and when you feel strong vibrations, your arrow is bent or the tips aren't straight....

I might be telling something that's already known, but it's a good and cheap way....

Frank