When I build decks, I typically use carriage bolts to secure the 4×4 handrail posts to the joists. Problem is, sometimes the carriage bolts start to spin because the square recess in the wood gets rounded and the bolt shank can’t get a good bite. This usually happens in soft woods such as red cedar, or when the posts have to be loosened for some reason. I hate to put a pair of pliers on a carriage-bolt head because it ends up scratched.
To solve this problem, as I’m inserting the bolt through the post I insert a nail, as shown in the drawing. The bolt may require some extra persuasion to get it through the hole. Use a rubber hammer or a wooden block to set the bolt without marking the head. With the nail shim installed, you should have no problem tightening the nut. If you do, add another nail.
Patrick Grieco, Toronto, None
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