Ok I figure I am going to get flamed on this one but I gotta ask any way.

While working on my Wristed Arm I didn't want there to be a lot of thread left so I just bought a 4" bolt and it has a 1 3/4" smooth shoulder. Now should I go get a bold with a 2 1/2" smooth shoulder and have extra threads left. I dont' want the tread on the outside because I don't want them to get banged up and never be able to take the bolt loose for whatever reason.

So I know I'm gonna get flameed for asking ANOTHER wristed arm question. But I just wanna build it right from the beginning. Thanx to all