Pinned

Arg! So much for ability for epoxy to stick to anything. The sample brass/wood/brass sandwich popped right apart when lightly smacked with a hammer. I don’t know if it was improper surface prep (I sanded (150) and cleaned with acetone), crappy epoxy (30 minute Bob Jones) or what but I sure don’t feel good about it. So, go old school and nail the infill in. The most important place is above the wedge as there is a lot of force there trying to remove the infill. I’m using 1/8” low fuming bronze brazing rod (the stuff you get at the welding store to braze steel with).
Pros: it is 0.001” over size so it will be a nice fit in a 1/8” hole. It is a different color from brass so you see, and admire, the pleasing pin placement and amazing craftsmanship it took to put them there (half serious – I do like to see construction details (like dovetails or finger joints).
Cons: harder than brass, crumbles if you try to mushroom it too much, visible. This bronze really isn’t an ideal material for the pins – it doesn’t mushroom as anywhere as nicely as 360 brass. Use only if you like the color.

Addendum: I epoxy’d two pieces of brass together and they are one. Color me confused.
Addendum2: Further testing shows that that cutting off the corners generated enough heat to caused the glue failure. I use a small power bandsaw to free hand the corners and gets the brass hot enough even though I don’t wear gloves (however, the cut area is too hot to touch). In my test, the failure was complete – the brass detached from the wood (in the glue) while being sawn. This article on West System epoxy indicates the epoxy I’m using can’t take the heat (unlike some epoxies).

Procedure:
– Drill holes and lightly ream with a tapered reamer. You want a shallow taper (maybe half way through the side) that the pin can expand into and wedge. Too big and you’ll never fill the hole.
– Cut some pins a little over 1/16” too long. Too much longer and and you’ll never be able to smash them all the way back to the sides. Lightly chamfer one face (the driven face).
– Tap in the pin, center it, lay it on the anvil and smack the pins a couple of times on each side to start the mushroom. Use a belled (curved) face hammer (less dent damage if you miss). The Japanese style hammer pictured has a flat face and a belled face (showing).
– Center punch the pin and then punch in a ring around the center. Don’t punch the edge or the punch will slip (or the pin edge will break) and you will dent the plate (really – a flaked edge leaves a crater). Use a rounded over or blunt punch – pictured is a el cheapo punch that I actually tried to use as a punch, which flattened the end and now I have a nicely rounded punch.
– Smack the pins with the hammer a few more times for good measure.
– File. Be surprised at how far away from the pin the brass has swollen, about one diameter.
– *NOTE* you don’t need much force. Control is your friend; miss and it creates a hell of a mess. Use shields (such as real thin washers). Use an anvil / big chunk of steel or you’ll just move the pin back and forth.

There are four pins in the photo: one freshly inserted, one peened, and two finished. The marks are from not cleaning the anvil (opps).

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