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First pour checklist

Most failed pours come down to a handful of things: the wrong depth, a cold shop, a leaky form or a sloppy mix. Tick these off before you open the cans. Your checks are saved on this device.

Days before

Pour day, before mixing

Mixing and pouring

After the pour

Tips from people who make epoxy

Quoted from manufacturer guides, data sheets and established woodworking publications. Your product's data sheet always comes first.

Heat and pour depth

  • Mass drives heat. "In a thicker mass, more heat is retained, causing a faster reaction and more heat." A cup of 8 fl oz or more can melt the cup and burn skin; the same amount spread thin stays cool. West System
  • "A 100-gram mass of mixed epoxy can reach 400°F." Move mixed epoxy to a wide, shallow container. West System
  • Deep-pour epoxy overheats too when poured past spec: "It is not uncommon for a mass of Fathom epoxy to reach 200-300°F or hotter if it is poured thicker than advised," which can cause shrinkage, cracks or yellowing. TotalBoat Fathom TDS
  • Some deep-pour products also need a minimum mass. Fathom's data sheet asks for at least 1/2 gallon of mixed epoxy per pour. TotalBoat Fathom TDS
  • "At warmer ambient temperatures, the epoxy will cure faster and generate more heat. Limit the depth of each pour, especially when working in warm conditions." Epoxyworks
  • "If a pot of mixed epoxy begins to exotherm (heat up), quickly move it outdoors." Don't throw it out until it has cooled. West System

Temperature and humidity

  • "Your workshop should be well ventilated and between 70° and 85° while you work with epoxy." Wood Magazine Family Handyman gives 70–80 °F as the typical best curing range. Family Handyman
  • Cold epoxy on warm wood can make air in the wood expand and "outgas," causing bubbles, craters and pitting. Bring them to the same temperature. Epoxyworks
  • Amine blush, a waxy film from low temperature or high humidity, can act as a bond breaker between layers. Stay at least 5 °F above the dew point, and skip fuel-burning heaters, which add moisture and carbon dioxide. Sherwin-Williams
  • To remove blush, "wash the surface with clean water (not solvent) and an abrasive pad," then dry it with paper towels. West System
  • Wood should be dried "ideally below 10-12% moisture content" before sealing it in epoxy. TotalBoat

Bubbles

  • Mix gently: "Keep your stir stick against the bottom of the mixing pot." Epoxyworks
  • Long-working-time deep pours can rest before pouring. Fathom's data sheet suggests 20–30 minutes in the pail so bubbles float up. TotalBoat Fathom TDS
  • With a torch, keep "approximately five inches from the surface and move the torch quickly in a sweeping motion," then keep checking for about two hours. Family Handyman
  • For small castings, a vacuum chamber removes bubbles before pouring and a pressure pot shrinks them after; Alumilite suggests a pot rated for at least 40–50 PSI. That advice is for their urethane resin, so check your product. Alumilite
  • "When using pigments the seal coat is not really needed, as the micro bubbles won't be visible." Canadian Woodworking

Forms, tape and release

  • Epoxy sticks to wood, glass and aluminum. It won't stick to sheathing tape, HDPE, Teflon, polyethylene, polypropylene, nylon, Mylar or silicone. EcoPoxy
  • Line the form with sheathing tape, Tyvek tape or release agent; with release wax, use 4–5 coats. TotalBoat Fathom TDS
  • "Seal every seam with hot glue to prevent leaks: even a pinhole gap can drain your entire pour." TotalBoat
  • "If the mold is not level, the epoxy will not cure evenly." Clamp the slabs to the form bottom to stop seepage. Family Handyman
  • Put a polyethylene sheet under the mold so any blowout lands on the sheet. EcoPoxy

Seal coats on wood

  • "Wood can also 'outgas' or release gasses as it warms, creating bubbles that get trapped in the epoxy." Epoxyworks
  • Apply "a very thin skim coat of epoxy to seal the surface, and allow it to cure before applying more epoxy." TotalBoat Fathom TDS
  • Timing differs by source: about 6 hours or until gelation (Epoxyworks), about half cured at 6–10 hours (Canadian Woodworking), or fully cured (TotalBoat). Follow your product's data sheet.
  • For flood coats, "plan to apply two coats. A thin first coat allows the air to escape." Wood Magazine

Measuring and mixing

  • "DO NOT attempt to adjust the epoxy cure time by altering the mix ratio." Most cure problems trace back to the wrong ratio. West System
  • Volume and weight ratios are different numbers, because resin and hardener have different densities. Fathom is 2:1 by volume but 100:44 by weight. TotalBoat
  • Mix 2–3 minutes scraping sides and bottom, then pour into a second pail and mix another 2–3 minutes. TotalBoat Fathom TDS
  • "Unmixed epoxy might be present on the bucket's edges," so don't scrape it into the pour. Family Handyman
  • As the wood absorbs epoxy the level drops, so "make sure to mix extra." Canadian Woodworking

Sanding and finishing

  • "Never breath the sanding dust of partially cured epoxy." Dust from fully cured epoxy is considered a nuisance dust. West System Epoxy Safety
  • One grit progression: 120, 180, 220, 320 (start wet sanding here), 400, 600, 800, 1200, 1500, 2000. Tape off the wood before polishing. Family Handyman
  • Wash off amine blush before sanding; it "can clog sandpaper and inhibit subsequent bonding." West System
  • Recoat windows are product-specific. For West 105/207: "make your next pour 3 to 12 hours after the previous pour" to avoid sanding, at 70–75 °F. Epoxyworks

Safety

  • "You may become sensitized to epoxy after many exposures or just one." West System Epoxy Safety
  • "The recommended minimum for most epoxy users is gloves, eye protection and protective clothing," plus a respirator with an organic vapor cartridge. West System Epoxy Safety
  • "Never use solvents to remove epoxy from your skin." For eyes, flush with low-pressure water for 15 minutes. West System Epoxy Safety
  • Even low-odor hardeners can be sensitizers. The SDS for West System 205 hardener lists H314 (severe skin burns and eye damage) and H317 (may cause an allergic skin reaction), and a deep-pour hardener from FGCI lists H317 and H318. Read your product's SDS. West 205 SDS · FGCI SDS
  • Spilled hardener on sawdust can heat up and "ignite the sawdust." West System

Sources checked Oct 5, 2026. Quotes are shortened; follow the links for full context.