I just upgraded my RB3011 to a RB4011 and the brackets on the 4011 are very loose but I only see 1 screw hole to affix to the router on each bracket… is this by design or am I doing something wrong…..?

Have installed a few of RB4011, yes - only one screw. Looks like this is by design.

Have installed a few of RB4011, yes - only one screw. Looks like this is by design.

So the brackets were still loose after you tightened the 1 screw?

I am worried about going to over tighten and break the screw...?

I also have a new 4011, and it's a crappy mounting design in my opinion. I added some double sided foam tape to the inside of the bracket which firmed it up a bit.