What size drill bit do i use to tap a hole for these 9/16 u-bolts
asked by: Derek L
Helpful Expert Reply:
Since the diameter size of the posts on this u-bolt is 9/16-inch you can ideally use a 9/16-inch or 5/8-inch bit (or even a 1/2-inch bit if you have the room to move the drill around enough to ream the hole to the required size). In either case you will want to ensure that the bits you are using are intended for drilling in the material on your trailer. Please refer to the photo provided which shows the dimensions of this item.
Often it is easier to start a smaller-diameter pilot hole, say a 1/8-inch size, and then use progressively larger and larger bits until you are at the final desired hole diameter. For drilling in metal a small application of cutting oil at the drilling site will help keep your drill bits from overheating and will also help to remove the metal fragments as the hole is bored out.
We do offer a U-Bolt Plate for this, part # 116308.