3230AB‑9T River Table Epoxy SOP

1) Key facts

• Mix ratio (by weight): A:B = 100:33. Do not mix by volume and do not assume 1:1.
• Viscosity (25℃): Part A 1000–2000 cPs; Part B ≤50 cPs. Good flow and natural defoaming.
• Pot life (25℃, 100 g): ~2 hours. Larger batches and warmer rooms shorten working time due to exotherm.
• Cure (typical): 25℃ ≈ 18–20 h to demold strength (100 g). 55℃ × 3 h (2 g) for heated cure. Deep pours need longer.
• Deep‑pour capability: With tight control of temperature, humidity, batch size, and cavity size, single pours of ~3–5 cm are feasible.
• Environment limits: Avoid room‑temp cure at RH >85% (amine blush risk). If <15℃, pre‑warm Part A only to ~30℃ before mixing.
• Thermal/mechanical: Shore D <85; Heat deflection temperature (HDT) ≈ 80℃. Use coasters; consider a UV‑resistant topcoat to reduce yellowing.

2) Volume & quick math

• Resin volume ≈ average river width × length × thickness (in cm). 1000 cm³ = 1 L. Add 10–15% extra.
• Mixed density (approx.): ≈ 1.10 kg/L.
• Fast split for total mixed mass M: Part A ≈ 0.752M, Part B ≈ 0.248M.
• Per 1 L mixed: ≈1.10 kg → A ≈ 0.83 kg, B ≈ 0.27 kg.
• Per 1.00 kg mixed: A ≈ 0.75 kg; B ≈ 0.25 kg.

3) Guidelines for 3–5 cm deep pours

• Ambient control: 18–22℃ is safer for limiting peak exotherm; RH ≤70%. Avoid direct sun and drafts.
• River width & batch size: For wide cavities (>20 cm), prefer two stages even for 3–5 cm total thickness.
• Batching: Keep each mixed batch ≤1.5–2.0 kg; use wide, shallow trays to dissipate heat. Pour back‑to‑back to maintain a wet edge.
• Wood pre‑seal: Apply a thin sealing coat of 3230AB‑9T on live edges/pores; wait tack‑free (~6–12 h) to reduce outgassing and bubbles.
• Two‑stage option: First pour to ~60–70% of target thickness; when surface is gel‑tacky (finger mark without transfer), pour the rest. If >24 h between pours, scuff (320–400 grit) and wipe with IPA.
• Defoaming: Sweep quickly with a heat gun/torch; keep it moving to avoid scorching or depressions.
• Cold weather: Pre‑warm Part A to ~30℃ (A only). Warming shortens pot life—work efficiently and in smaller batches.
• Pigments: Total pigment/ink ≤3% of resin to minimize settling and heat rise. Avoid water‑based or silicone‑containing additives.

4) Standard workflow

1. Wood prep: Moisture content <10–12%; clean bark/dust. Stabilize large cracks (thin epoxy or CA + wood dust). Apply a thin sealing coat.
2. Mold & sealing: Use HDPE or melamine with PE tape/release wax. Seal seams with neutral silicone; let cure and leak‑test. Clamp/weight slabs to prevent float; isolate contact points to avoid sticking.
3. Color test: Trial mix at 100:33 by weight. Adjust pigments conservatively (≤3%) to ensure clarity and stability.
4. Mix & pour: Weigh accurately; mix 3–5 min scraping sides/bottom; rest 3–5 min; pour. For deep pours, keep batches ≤1.5–2.0 kg and pour consecutively; defoam promptly.
5. Cure & post‑cure: Maintain stable temp/RH. Deep pours typically need 48–72 h+ to demold; full properties develop later. Optional post‑cure: after initial set, 40–55℃ for several hours with slow ramp up/down.
6. Demold & flatten: Trim flash; flatten via router sled/WBS/CNC. Ease edges (chamfer/round) to improve feel and durability.
7. Sanding & finishing: Sand 80→120→180→240→320→400→600→800→1000→2000. Polish resin if desired. Finish with hardwax oil (easy repair) or UV‑resistant PU clear; degrease with IPA before finishing.
8. Assembly: Use slotted hardware/Z‑clips to allow wood movement; pre‑drill; avoid over‑tightening.

5) Common issues & fixes

• Excess bubbles/outgassing
  Causes: No pre‑seal; cold/high viscosity; aggressive mixing.
  Fix: Pre‑seal; keep 20–25℃ or pre‑warm A; gentle stir; quick heat‑gun/torch sweep.
• Overheat, cracks, sink marks
  Causes: Oversized batches; hot room; poor heat dissipation.
  Fix: 18–22℃ room; batches ≤1.5–2.0 kg; shallow trays; split into two pours if needed.
• White haze (amine blush)
  Causes: RH >85% during cure.
  Fix: Lower RH or post‑cure. If present, after full cure wash with warm water + mild detergent, then scuff and refinish.
• Sticky/soft surface
  Causes: Wrong ratio; poor mixing; low temp/high RH; inhibited cure at the surface.
  Fix: Scrape off; solvent wipe; sand; re‑coat at 100:33 by weight; ensure 20–25℃, low RH; allow more time.
• Fish‑eyes/craters
  Causes: Oils, waxes, silicones, hand lotions, or silicone polishes.
  Fix: Two IPA wipes; ultra‑thin seal coat; avoid silicone products and contaminated rags.
• Pigment settling/muddy swirls
  Causes: Too much pigment; over‑working; high exotherm increasing flow.
  Fix: ≤3% pigments; gentle swirl; cooler room and smaller batches; place effect layers mid/upper depth.
• Leaks
  Causes: Poor mold sealing or through‑cracks in wood.
  Fix: Silicone all seams; prime‑pour a small amount to check for leaks before the main pour.
• Yellowing and heat marks
  Causes: UV exposure; hot objects; HDT ≈80℃.
  Fix: Avoid direct sun; apply UV‑resistant topcoat; always use coasters or trivets.

6) Quick example (with weights)

• Target top: 120 × 60 × 4 cm, average river 15 cm → volume ≈ 7.2 L; prepare ≈ 8.0 L.
• Mass: 8.0 L × 1.10 ≈ 8.8 kg total → A ≈ 6.62 kg; B ≈ 2.18 kg.
• Deep pour option 1 (single): 18–22℃; river width ≤18–20 cm; multiple back‑to‑back batches ≤1.5–2.0 kg to reach 3–4 cm; demold ~48–72 h+.
• Deep pour option 2 (two stages): First 2.5–3.0 cm; top up at gel‑tacky to final thickness. If >24 h between pours, scuff (320–400 grit) and degrease with IPA.

7) Safety & disposal

• PPE: Organic vapor mask, nitrile gloves, eye protection. Work in a well‑ventilated area. Wash hands after use.
• Keep away from flames and children/pets. Avoid releasing to the environment.
• If <15℃, pre‑warm Part A to ~30℃ (A only). Avoid room‑temperature cure at RH >85%.
• Cleanup: Wipe tools with ≥91% IPA or dedicated cleaner before cure. After cure, mechanical removal only.
• Waste: Allow leftovers to fully cure in small amounts; dispose as solid waste per local regulations. Never pour liquid resin into drains.

Data integrated from the 3230AB‑9T product sheet and best practices for river‑table epoxies. Values are typical at 25℃, ~70% RH and for small test masses; adjust for your setup.