Appalachian Barn Gun Kit (Percussion) — Notes on Fitting Parts to Stock

To obtain a tight wood-to-metal fit, it is advisable to have a slight draft (2–3 degrees is typical) on most metal parts being fit. This draft is included on the appropriate parts, but it is usually beneficial to clean up the part edges just slightly with a fine file before fitting. Maintain the slight draft during this process.

Inlets have been designed so that parts will either fit with little to no work or be just slightly tight, allowing for variations in cast part size. When fitting parts that are slightly tight, wood can be trimmed with a very sharp chisel, knife, or gouge. Small amounts of metal can also be removed from the part edges.

Using a transfer color to indicate tight spots is advisable. This can be soot from a candle, soot mixed with a small amount of oil and brushed on the part, Prussian blue, or similar. Use only a very small amount of transfer color when fitting.

Tip: Whenever a later step tells you to “adjust the fit,” return to these notes. The same transfer-color-and-trim process applies to every metal part.