West System 209 Extra Slow Hardener

209 is the extra slow hardener for West System 105 resin: 3:1 by volume, 40 to 50 minutes of pot life in a 100 g cup at 72°F (22°C), about twice the working time of 206. It is the hardener for hot, humid shops and for big layups and glue-ups where 206 still kicks before you are done. In a thin film you get 3 to 4 hours of working time at 72°F; it goes solid in 20 to 24 hours and reaches maximum strength in 4 to 9 days. Keep the work at 70°F (21°C) or warmer: below that the cure drags and 206 slow is the better pick. It is not a clear-coating hardener; for bright wood use 207 special clear. 105/209 bonds, laminates and builds barrier coats on fiberglass, wood, foam and metal, and it thickens with any West System filler. It meters with the 207/209 hardener pump in the 300 Mini Pump Set, and the 209-SC jug comes with the Group C extension tubes. Specs Ratio 3 parts 105 resin to 1 part 209 by volume (3.68:1 by weight); meters with the 207/209 pump in the 300 Mini Pump Set Mixed viscosity 650 cps at 72°F Pot life 40 to 50 min (100 g at 72°F) Working time 3 to 4 hr in a thin film at 72°F Cure solid in 20 to 24 hr; maximum strength in 4 to 9 days; minimum temperature 70°F Cured strength tensile 7,300 psi (ASTM D-638); flexural 12,500 psi (ASTM D-790); HDT 117°F (105/209) Sizes 209-SA 10.6 fl oz, 209-SB 42.2 fl oz (0.33 gallon), 209-SC 1.45 gallon Buy 209 when heat or the size of the job is what beats you. In summer heat 206 can kick in the cup before a long layup is wet out; 209 roughly doubles that window. Match the size to your resin, 209-SA with the 105-A quart, 209-SB with the 105-B gallon, 209-SC with the 105-C jug, so the pumps meter right from both cans. See the full West System lineup.