A tip cleaning assembly for use with an extrusion head of an extrusion-based layered deposition system, the tip cleaning assembly comprising a support component, a purge ledge assembly mounted on the support component, at least one set block mounted on the support component adjacent the purge ledge assembly, and at least one contact head removably mounted on the first set block, where the at least one contact head is configured to engage at least one extrusion tip of the extrusion head.