I am in complete agreement with Francis. I too have had recent experience of having to refit pins to a brand new, quite expensive, set of pipes as the ones fitted fell out after a short time of playing. I take great care to fit the pins in my sets so that they have a firm sliding fit (AKA light push fit) in the pin holes on the chanter and a free fit in the key pivot hole. I have found a method that makes this quite straight forward to achieve. I use hard drawn brass wire Ø1mm. I drill the pin holes in the chanter with a Ø1mm drill. The resulting fit is too tight to push a pin in so I make an old fashioned "D" reamer from the same wire. Using this to ream out the holes eases the fit to a light push fit. My pins have never fallen out on any of the sets I have made and they can be removed from either side of the block without fear of splitting the block. a couple of strokes with a fine file will resharpen the cutting edge and once it is worn too short another is easy to make.
I have tried taper pins as mentioned in an earlier thread but only in a test piece. I don't have any confidence that they will be sufficiently reliable in use as the inevitable changes that the wood undergoes can easily cause the pin to loosen and as soon as it is slightly loose it will fall out.
One way of tightening a pin that is just a bit loose is to squeeze the last 1mm of the pin with flat nose pliers to make it oval and thus tighter.
I would never glue a pin in as it will make life hard for future repairers.
