200PC. SALE. TRADE PACK - Galvanised Square Drive Chipboard Screws for treated pine 8g x 25mm 200pc. Don't Pay $10.00. $7.32. Details. Add to …Spread a thin layer of glue along the edge of the plywood and screw the plywood to the shelf nosing. 1 3/4" screws work best for 3/4" T&G plywood or OSB. , the wood structural sheathing did not govern the capa. Use either 11⁄ 4 1galvanized roofing nails or 1⁄ 4 …The SPAX-M MDF screws are designed for joining MDF boards, chipboard, plywood, melamine, fiberboard and other engineered wood products. The SPAX CUT tip allows screwing into the material without predrilling, all without splitting or bulging the board or veneer. The ground serrations of the screw ensure quick and secure fastening and the milling ...Sep 03, 2019 · 50. Country: Reynard - the basic formula for screws is 1/3 = thickness of material to be fixed & 2/3 into the support. So for your 18mm ply, screw length is 18 x 3 = 54mm ... the newest screw to this is 50mm that's the size you use. 200mm apart is fine.