Rectangle Resin Mold Calculator
Determine the exact weight, volume, and mixing ratios for rectangular resin castings. Free interactive tool with custom waste sliders. Adjust the parameters in the interactive workbench below to get immediate recipe card outputs.
Resin Volume Estimator
Scale from 1 prototype to full production run
MEASUREMENT OUTPUTS
Recipe & Batch Summary
Studio Batch of 1 piece of rectangle mold (10cm x 10cm x 2cm) using Generic Epoxy: • Per Single Unit: 121.0g Resin (A) + 121.0g Hardener (B) [Total: 242.0g]. • Total Studio Run (1 Units): 121.0g Resin (A) + 121.0g Hardener (B) [Total Mass: 242.0g]. • Mix Ratio: 1:1 | Safety Margin: 10%.
MakerRatio • Studio Workshop Batch Sheet
https://makerratio.com • Precision Craft Formula Record
Date: _______________
Batch #: ____________
Project: Generic Epoxy (rectangle x 1)
Category: Epoxy Resin
Dimensions: 10 x 10 x 2 cm (x1)
Mix Ratio: 1:1 | Batch: 1 unit(s)
Specific Gravity: 1.1 g/ml
Safety Spill Margin: 10%
Batch Mix Breakdown (By Exact Weight)
Workshop Safety & Quality Protocol:
[ ] Ambient room temp 70°F–78°F (21°C–25°C) & mold leveled.
[ ] Protective nitrile gloves on & workspace ventilation active.
[ ] Mix thoroughly scraping sides and bottom for 3 full minutes.
[ ] Verify pot life and demold window per manufacturer TDS.
Curing Schedule Log:
Pour Time: ___________
Gel / Tack-Free: ______
Demold Time: ________
Recommended Materials & Tools for this Project
Puduo 1:1 Crystal Clear Tabletop Epoxy
Formula: 1:1 mix ratio. High-gloss self-leveling surface coating for countertops, tumblers, and shallow mold castings.
Heavy-Duty Silicone Coaster Molds Pack
Specification: Flexible, tear-resistant platinum silicone molds (circle and hexagon) with thick sidewalls to prevent bowing.
Transparency Notice: As an Amazon Associate, MakerRatio earns from qualifying purchases at zero extra cost to you. Product recommendations are selected based on verified Manufacturer Technical Data Sheets (TDS). Always consult chemical safety data before pouring.
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To calculate the exact volume and weight splits for this craft project, the workbench executes the following geometric equations:
Rectangular Silicone Mold Sizing & Weight Matrix
1.10 g/ml Specific GravityComprehensive material weight splits and volume calculations across standard commercial rectangular silicone molds for resin casting.
| Mold Style & Dimensions (L × W × D) | Geometric Volume (ml) | Specific Gravity | Mixed Resin Weight (g) | Part A (1:1 Wt) | Part B (1:1 Wt) |
|---|---|---|---|---|---|
| Bookmark Mold (14 × 3 × 0.3 cm) | 12.6 ml | 1.10 g/ml | 13.9 g (0.49 oz) | 7.0 g | 7.0 g |
| Set of 28 Dominoes (5 × 2.5 × 0.8 cm) | 280.0 ml | 1.10 g/ml | 308.0 g (10.86 oz) | 154.0 g | 154.0 g |
| Square Coaster (10 × 10 × 1.0 cm) | 100.0 ml | 1.10 g/ml | 110.0 g (3.88 oz) | 55.0 g | 55.0 g |
| Small Trinket Tray (18 × 10 × 1.5 cm) | 270.0 ml | 1.10 g/ml | 297.0 g (10.48 oz) | 148.5 g | 148.5 g |
| Medium Serving Tray (25 × 15 × 1.5 cm) | 562.5 ml | 1.10 g/ml | 618.8 g (21.83 oz) | 309.4 g | 309.4 g |
| Deep Floral Block (10 × 10 × 5.0 cm) | 500.0 ml | 1.08 g/ml (Deep Pour) | 540.0 g (19.05 oz) | 360.0 g (2:1) | 180.0 g (2:1) |
| Large Charcuterie Slab (35 × 25 × 2.0 cm) | 1,750.0 ml | 1.10 g/ml | 1,925.0 g (67.90 oz) | 962.5 g | 962.5 g |
In-Depth Crafting Guide & Density Analysis
Calculating the exact material weight for a rectangular resin mold (such as vanity trays, floral blocks, bookmarks, dominoes, and charcuterie slabs) requires correcting for polymer specific gravity. While water has a density of 1.0 g/ml, liquid epoxy resins range from 1.08 to 1.15 g/ml depending on formulation.
This rectangle resin calculator multiplies inner cavity dimensions by material density presets, incorporates an adjustable waste buffer, and provides precise Part A and Part B splits for digital scale pouring.
Frequently Asked Questions (Rectangle Resin Mold Calculator)
Why is mixed epoxy resin weight 10% to 13% heavier than water volume?
Standard liquid epoxy resin and hardener have a specific gravity of 1.10 g/ml to 1.13 g/ml, whereas pure water is 1.00 g/ml. If you calculate that a mold holds 500 ml of water and weigh out 500 grams of resin, your pour will fall short by ~50 to 65 grams, creating an incomplete, sunken casting.
How do you split a 1:1 by volume epoxy ratio using a digital gram scale?
For most hobby 1:1 casting resins (ArtResin, Let's Resin), Part A resin and Part B hardener have nearly identical densities (~1.12 g/ml Part A vs ~1.08 g/ml Part B). In practice, dividing the total calculated gram weight equally by 2 yields a perfect stoichiometric cure.
How do you prevent thermal cracking when pouring a deep rectangular flower block?
Rectangular molds deeper than 2 inches (5 cm) trap heat in their geometric core. You must use a slow-curing Deep Pour epoxy (2:1 or 3:1 ratio) with a 60+ minute working time. Using 1:1 tabletop resin in a deep block will boil, crack, and turn yellow.
How much waste factor should you add for rectangular silicone molds?
Always add 5% to 8% extra resin. Thick viscous resin clings to the sides and bottom corners of mixing containers, and flexible silicone walls bow outward slightly under the hydrostatic weight of liquid epoxy.
How do you calculate the volume of a rectangular mold with rounded corners?
Multiply Length × Width × Depth using the inner cavity dimensions, then subtract 2% to 4% to account for the rounded corner radius.
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