Resin Mixing Ratio Calculator
Get perfect resin mixing ratios every time with our professional calculator. Eliminate curing failures, soft spots, and waste with precise measurements tailored to any epoxy resin brand and project size.
Common Mixing Ratios Quick Reference
2:1
Most Popular
2 parts resin : 1 part hardener
66.7% resin, 33.3% hardener
1:1
Table Top Epoxy
Equal parts
50% resin, 50% hardener
3:1
Casting Resin
3 parts resin : 1 part hardener
75% resin, 25% hardener
5:1
Marine Epoxy
5 parts resin : 1 part hardener
83.3% resin, 16.7% hardener
Always verify: Check your specific product label - ratios vary by manufacturer
Precise Mixing Calculations by Project Size
Small Pendant (50g total)
Ratio: 2:1
Perfect for jewelry and small crafts
Coaster Set (200g total)
Ratio: 1:1
Table top epoxy for functional items
Art Panel (500g total)
Ratio: 3:1
Casting resin for artistic projects
River Table (2000g total)
Ratio: 2:1
Large pour with standard ratio
Keychain Batch (100g total)
Ratio: 3:1
Multiple small items
Cutting Board (1000g total)
Ratio: 1:1
Food-safe epoxy application
Professional Mixing Process
Calculate Your Ratios
Determine exact amounts based on your project needs
Key Actions:
- Use our calculator to determine total resin needed
- Check manufacturer specifications for your brand
- Calculate resin and hardener amounts separately
- Add 10% extra for mixing losses and waste
Pro Tip:
Weight is more accurate than volume - always use a digital scale
Prepare Workspace & Materials
Set up for safe and accurate mixing
Key Actions:
- Work in 70-75°F temperature (21-24°C)
- Ensure good ventilation and wear safety gear
- Have digital scale, mixing cups, stirring stick ready
- Lay out drop cloths and have cleanup materials nearby
Pro Tip:
Temperature affects cure time - too cold prevents proper curing
Measure Components by Weight
Precise measurement is critical for proper cure
Key Actions:
- Zero (tare) your scale with empty container
- Add resin first to calculated weight
- Zero scale again, then add hardener
- Double-check measurements before mixing
Pro Tip:
Even 5% deviation in ratio can cause cure problems
Mix Thoroughly
Complete mixing ensures proper chemical reaction
Key Actions:
- Mix for minimum 3-5 minutes (longer for large batches)
- Use figure-8 or folding motion, not circular stirring
- Scrape sides and bottom frequently during mixing
- Look for uniform color and consistency
Pro Tip:
Under-mixing causes soft spots and incomplete cure
Apply Within Pot Time
Work quickly before mixture begins to cure
Key Actions:
- Check pot time on product specs (usually 20-45 minutes)
- Pour immediately after mixing is complete
- Work in thin layers for thick applications
- Remove bubbles with heat gun or torch if needed
Pro Tip:
Larger batches have shorter pot times due to heat buildup
Popular Brand Mixing Ratios & Specifications
| Brand/Product | Ratio | By Weight (100g total) | Pot Time | Work Temp |
|---|---|---|---|---|
| EpoxyPlus Table Top | 1:1 | 50g : 50g | 30 min | 70-80°F |
| West System 105/205 | 5:1 | 83.3g : 16.7g | 20 min | 60-80°F |
| EnviroTex Lite | 1:1 | 50g : 50g | 25 min | 70-85°F |
| ArtResin | 1:1 | 50g : 50g | 45 min | 72-75°F |
| TotalBoat 5:1 | 5:1 | 83.3g : 16.7g | 22 min | 70-80°F |
| Pro Marine Supplies | 1:1 | 50g : 50g | 40 min | 70-85°F |
| Entropy Resins CLR | 2:1 | 66.7g : 33.3g | 30 min | 70-78°F |
| System Three | 2:1 | 66.7g : 33.3g | 25 min | 70-85°F |
| Fiberglass Coatings | 3:1 | 75g : 25g | 35 min | 70-80°F |
| Smooth-Cast 325 | 1:1 | 50g : 50g | 7 min | 73-75°F |
* Always verify ratios with current product documentation - specifications may vary by batch or formulation
Avoid These Critical Mixing Ratio Mistakes
Measurement Errors
- • Using volume measurements instead of weight
- • Eyeballing ratios instead of precise measuring
- • Not accounting for container weight (tare function)
- • Assuming all brands use the same ratio
- • Using old or contaminated measuring tools
Application Errors
- • Working in wrong temperatures (too hot/cold)
- • Exceeding pot time before application
- • Under-mixing the components
- • Not accounting for batch size heat buildup
- • Ignoring humidity effects on curing
Safety Guidelines for Resin Mixing
Critical Safety Warning
Epoxy resins contain chemicals that can cause skin, eye, and respiratory irritation. Some components are potential sensitizers and carcinogens. Always follow proper safety protocols.
Personal Protection Equipment (PPE)
- Gloves:Nitrile or vinyl disposable gloves. Replace if torn or contaminated.
- Eyes:Safety glasses or goggles, especially when mixing large batches.
- Respiratory:N95 mask minimum; organic vapor respirator for enclosed spaces.
- Clothing:Long sleeves, closed shoes, apron or coveralls for large pours.
Workspace Safety
- • Work in well-ventilated area (exhaust fan recommended)
- • Maintain temperature between 70-75°F (21-24°C)
- • Keep humidity below 50% for optimal curing
- • Have eyewash station or clean water nearby
- • Keep fire extinguisher accessible (Class B for flammable liquids)
- • Cover work surfaces with plastic or cardboard
Emergency Procedures
Skin Contact:
Remove contaminated clothing. Wash immediately with soap and water for 15+ minutes. Seek medical attention if irritation persists.
Eye Contact:
Flush immediately with clean water for 15+ minutes. Remove contact lenses if present. Seek immediate medical attention.
Inhalation:
Move to fresh air immediately. If breathing difficulties persist, seek medical attention.
Proper Disposal
- • Allow waste resin to fully cure before disposal
- • Dispose of cured resin in regular trash
- • Take uncured liquid resin to hazardous waste facility
- • Clean containers with denatured alcohol before disposal
- • Never pour liquid resin down drains
- • Store resin components away from heat and ignition sources
Resin Mixing Troubleshooting Guide
Problem: Resin Won't Cure (Stays Tacky)
Likely Causes:
- •Incorrect mixing ratio (most common cause)
- •Insufficient mixing time (under 3 minutes)
- •Temperature too cold (below 65°F)
- •High humidity (above 70%)
- •Contaminated resin or hardener
Solutions:
- 1. Check and recalculate your mixing ratios
- 2. Scrape off tacky layer, re-mix and pour new layer
- 3. Increase workspace temperature to 75°F
- 4. Use dehumidifier if humidity is high
- 5. Test resin components with small batch first
- 6. Consider using fast hardener for cold conditions
Problem: Resin Cures Too Fast (Short Pot Time)
Likely Causes:
- •Ambient temperature too high (above 80°F)
- •Batch size too large (creates exothermic heat)
- •Wrong hardener type (fast vs. slow)
- •Direct sunlight or heat sources
Solutions:
- 1. Cool workspace to 70-75°F
- 2. Mix smaller batches (max 500ml at a time)
- 3. Use wider, shallower mixing containers
- 4. Switch to slow hardener formulation
- 5. Chill resin components before mixing (not below 65°F)
- 6. Work in shaded area, avoid direct sunlight
Problem: Bubbles in Cured Resin
Prevention Strategies:
- • Warm resin to 75-80°F before mixing (reduces viscosity)
- • Mix slowly and steadily, avoid whipping air in
- • Let mixed resin sit 2-3 minutes for bubbles to rise
- • Pour in thin stream from height of 12-18 inches
- • Use vacuum chamber for critical applications
Bubble Removal Methods:
- • Heat gun: Hold 6-8" away, move constantly
- • Propane torch: Quick passes, don't linger
- • Hair dryer: Warm air to encourage bubbles to surface
- • Toothpick: Pop large bubbles manually when wet
- • Alcohol spray: Light mist can break surface tension
Problem: Cloudy or Yellowing Resin
Common Causes:
- • Moisture contamination in resin or hardener
- • Condensation from temperature changes
- • UV degradation (yellowing over time)
- • Poor quality or old resin components
- • Reaction with certain pigments or additives
Prevention & Solutions:
- • Store components in sealed, dry containers
- • Allow components to reach room temperature before mixing
- • Use UV-resistant resin formulations for outdoor projects
- • Check expiration dates on all components
- • Test pigments/additives in small batches first
- • Sand and recoat if yellowing is surface-level
Advanced Professional Mixing Techniques
Temperature-Controlled Mixing
Professional Tip: Control both ambient and material temperatures for consistent results.
Optimal Temperature Zones:
- • Resin components: 70-75°F
- • Workspace: 72-76°F
- • Pour surface: 68-75°F
Pro Techniques:
- • Use infrared thermometer for accuracy
- • Warm cold components in water bath
- • Use heated mixing plates for large batches
- • Monitor temperature throughout mixing process
Precision Measurement Systems
Professional Standard: ±0.1g accuracy for batches under 1kg, ±0.5g for larger batches.
Recommended Equipment:
- • Digital scale: 0.1g resolution minimum
- • Multiple mixing containers (pre-weighed)
- • Graduated syringes for small batches
- • Calibration weights for scale verification
Quality Control:
- • Calibrate scales monthly
- • Use dedicated measuring tools for each component
- • Document all batch measurements
- • Verify ratios with test pours
Production Batch Management
Commercial Approach: Optimize batch sizes and timing for maximum efficiency and quality.
Batch Size Guidelines:
- • Small projects: 100-500ml batches
- • Medium projects: 500ml-2L batches
- • Large projects: 2L+ (consider multiple pours)
- • Production runs: Standardize to 1L or 2L batches
Timing Optimization:
- • Mix only what you can use in pot time
- • Stagger batch preparation for large pours
- • Account for 15-20% longer mixing time for large batches
- • Plan for temperature rise in large batches
Quality Assurance Testing
Professional Practice: Test every batch for consistency and quality before full application.
Test Protocols:
- • Pour 50ml test sample from each batch
- • Monitor cure time and final hardness
- • Check for cloudiness, bubbles, or soft spots
- • Document results for quality tracking
Documentation Standards:
- • Record batch numbers and ratios
- • Note environmental conditions
- • Track cure times and final properties
- • Maintain testing log for reference
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