Drilling template for hole 145mm

thingiverse

A drilling template for creating a precise hole, 145mm in diameter, within a stone wall. The center hole is a neatly defined 12mm in diameter, surrounded by two outer holes measuring 8mm each. Initially, I used an 8mm drill bit to establish the foundation, then carefully progressed to a 10mm drill bit, followed by a 12mm drill bit, and finally, a 14mm drill bit, skipping one hole at a time. This drilling template has already been utilized extensively, resulting in noticeable wear and tear as evidenced by visible damage on the photograph. To secure the template firmly in place, I first drilled a precise 12mm hole through the wall. Next, I inserted a long threaded rod, which spanned across both sides of the wall, anchored with bolts to maintain its position. Additionally, I placed an extra bolt within one of the pre-drilled 8mm holes to prevent any movement or shifting of the template.