[CAUT] pin-block plugging?

[Ron Nossaman]

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