I've been reading of the disappointing results people have had plugging blocks with 3/8" plugs. I've plugged two blocks in 30+ years, both times with 1/2" plugs and Titebond, with no problems other than the time it takes. I've never considered the 3/8" plugs substantial enough to use. Consider that you are putting a 0.282" pin into a 0.375" plug. If you are using a high density block like Falconwood or Delignit, you'll be drilling somewhere in the range of 0.266"-0.272" pilot hole. That leaves a "tube" of plug that's, at most, 0.055" wall thickness. Any deviation in drilling angle and centering will very possibly put you out of the plug altogether in some area. A thin walled tube of cross ply wooden laminate won't have a heck of a lot of physical integrity. If there's any spring left to the old block, driving in a pin will fracture the plug and expand it into the block, resulting in less of an interference fit and lower pin torque than you would have gotten in a new block. A 1/2" plug would leave at least a 0.117" wall, which still isn't a lot, but is substantially more solid than the 3/8" plug. My take, for what it's worth. Ron N
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