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Pilot Hole size for Softwood | Lag Screw Diameter | Pilot Hole dimension for Hardwood |
3/32″ | 1/4″ | 3/16″ |
9/64″ | 5/16″ | 7/32″ |
11/64″ | 3/8″ | 1/4″ |
1/4″ | 1/2″ | 11/32″ |
5/16″ | 5/8″ | 1/2″ |
3/8″ | 3/4″ | 9/16″ |
Lag Screws in Softwoods
When drilling right into softwoods, it’s always worth make the efforts a smaller sized sized bit. The lower thickness wood fibers permit for higher compression once receiving the screw. This results in an as whole tighter to the right and much more secure fastener. There space a couple of exceptions to this like fragrant cedar and also other difficult softwoods. If friend aren’t sure just how if you need to test a smaller drill bit, we have actually a chart through all the hardness ratings for North American softwoods. Despite there’s no must countersink your lag screw, us recommend smoothing the surface.
Lag Screws in Hardwoods
The most difficult part through hardwoods is steering in the actual lag screw. If you have a pack of seed setter bits, you’re in great shape…at the very least for the smaller sizes. Because that the other users the end there that will be utilizing a socket on a 1/4″ hex shank, it’s a different story. As the lag screw enters deeper into the pilot hole, the socket will likely ground out before the screw is fully inside. When you conference this, stuff some little washers right into the ago of the socket. This will effectively make the socket shallower when it wraps about the lag screw’s head. Carry out be mindful that it is of food safer and also quicker to use nut setter bits.
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