Hi guys,

I am interested if having two holes per tube-to-tube connection is harmful to the possible weakening of the part compared to having a larger single hole/bolt.

Here's the setup:



I am considering 2 M5 bolts per 20x20mm tube but I have been advised to change that to one M6 bolt in the center.

I am thinking that bringing the bolts closer to the tube's walls will actually improve the situation as the crushing force necessary to tighten the bolts will be dissipated in the wall rather then in the bowing of the upper/lower surfaces the bolt goes through.
What do you think?