Why you should pin. Strengthen the joint between parts, conversions or repair broken parts. It is possible, with practice, to pin broken arms, legs and weapons.
What you need.
Pin vice, drill bits, glue, sharp hobby knife, files, wire cutters, needle nose pliers, wire, papertowel or Qtips and alcohol. If you have one a dental tool.
First fit the two pieces together, to see how they fit. You need to figure the best location and angle for the pin. Sometimes you have flat surfaces, other times you will have a round piece that fits into a cup.
First thing I do is mark the location to drill by making a little indentation “prick” in the location I am going to drill. This is to prevent the drill bit from wandering when you start the hole.
If your first hole is on a round piece or cone ( the part that fits in a the cup)j, it helps to file a small area flat. This allows a good spot to make the prick and start the hole.
Make sure your drill size matches you wire To large a hole will allow the wire to wobble and break the joint once it is glued. For thin drill, less than a millimeter, keep as much of the drill inside the pin vice as possible. It is easy to break small drill bits. Keeping them short make it less likely to that you will bend the bit with to much pressure.
The pin vice needs to be lined up with the prick and spin the drill to start the hole. After a few spins of the drill you may want to clean the shavings from the drill head. Once you have hole drilled test fit the wire. It should go in at least 3x the width of the wire. If you want a really strong bond, clean the wire with the alcohol. Put a spot of glue on wire and press it in. Use the Qtip/papertowel to remove excess glue.
Use your wire cutters to trim the wire. You don’t need to trim it to the perfect length right now. Usually 1/8″ – 1/4″ works well.
Next you use the pin you have inserted to make the other spot. You can press the pieces together and use the wire to scratch the metal. I prefer to put a small spot of paint on the wire and use that to mark next hole. Use the dental pick to make the prick for the next hole. Drill it. Once you think you have the second hole. Test fit the parts. You will probably have to use you wire cutters to shorten the wire. Before you test fit again, use a flat file to square of the wire. The end you cut will have a ===> at the end. If you file the end off, you get a more wire into the second hole.
Test fit the parts again. Bending the wire a little if the second hole doesn’t line up perfectly is an options. You may have to drill and or trim again until you get a good fit.
Clean both side with alcohol. The oil from you fingers make a difference. You can also rough up the surface with a file, just a little make a better connection.
Glue one side and put it together. Which side, depends on the joint. I usually put the glue in the one like a cup. If it is flat, pick one. Press it together. Have a papertowel or Qtip available to remove excess glue.
On miniatures with a body and a weapon that attaches to two points can be a problem. If you pin both arms, you may not be able to fit them together. I normally pin one arm and glue the other.
Pinning takes time and patients. I have been able to pin broken spear shafts, Jack arms and legs. It takes time and practice. If you think that part might fall off you probably need to pin it.