Build wiki for a small 3-tier pine bookshelf. Topics: DIY Materials, DIY Measurements, DIY Steps, DIY Tools, DIY Safety, DIY Costs. Dated correction: DIY Correction 2026-10-01 replaces the old 36 in board length with 38 in everywhere. Q1 How many boards and what length? 6 boards cut to 38 in, see DIY Materials and DIY Correction 2026-10-01. Q2 Which tools are required? Circular saw, drill, countersink bit, tape measure, carpenter square, 4 clamps, orbital sander, see DIY Tools. Q3 What are the shelf spacing and overall height? 12 in spacing, 30 in tall, see [DIY Measu