The tools, etc., of the "Pennsylvania Gun Factory"--run by Peter Dehaven--were inventoried on 18 January 1779. The contents were sold to James Pearson, Benjamin Rittenhouse, and Peter Dehaven on 18 and 19 January 1779.
These inventories offer a good picture of what a "Gun Factory" would have contained:
You can learn more about this gun factory from Wayne Heckert's article: “Rifles and Muskets on the Swatara: Clandestine Hummelstown Factory Armed the Revolution,” Kentucky Rifle Association Bulletin 34, no 1 (2007): 3–6.
These inventories are at the PA State Archives at Harrisburg, among the Records of Pennsylvania’s Revolutionary Governments, 1775-1790 (54 Reels): Reel 14, Images 941-946.