Resin Coaster Set
Coasters are the right first resin project because the volume is small, the mould does the shaping, and a mistake costs a few millilitres rather than a whole table top. Mix more resin than the mould volume suggests: under-mixing is the most common failure, and a 10 to 15 percent allowance is normal.
Plan this project at my size -> The planner scales the material list and the time estimate to the size you want.
What it costs in materials
The quantities below are a basis, not a shopping list. Each one is stated per unit of the scale this project is measured in, and the planner multiplies it by the size you choose and adds your waste allowance. Where the quantity is 0 the item is a tool or a piece of equipment you either have or do not: a larger version of the same project does not need more of it.
| Material | Quantity basis | Notes |
|---|---|---|
| Epoxy resin and hardener | 45.00 millilitres per coaster | A 10 cm round coaster about 8 mm deep holds roughly 63 ml. Read this as the mixed total. |
| Coaster moulds | 1.00 moulds per coaster | Silicone, and reusable. You need fewer moulds than coasters if you pour in rounds. |
| Pigment | 2.00 millilitres per coaster | About 3 to 6 percent of the resin volume. Far less for translucent effects. |
| Mixing cups | 2.00 cups per coaster | One for measuring, one for mixing. Do not reuse a measuring cup as a mixing cup. |
| Stir sticks | 2.00 per coaster | |
| Nitrile gloves | 4.00 gloves per coaster | Uncured resin is a skin sensitiser. Change them when they get tacky. |
These figures do not include prices, on purpose. Material prices change by supplier, season and country, so the planner asks you to check them yourself rather than presenting an invented number as a fact. Scale this list to your size ->
How long it takes
- Working time
- 0.5 hours
- Finishing
- 3.0 hours
- Example at 4 items
- 5.0 hours
per items of count
Blocking, seaming, curing or mounting, on top of the working time
The planner gives you this figure for whatever size you enter
These are estimates for someone working steadily, not for a first attempt at a new technique and not for a rushed one. Most people take longer on the first version and much less time on the third, which is why the planner also shows a stretch estimate about a quarter higher than the working figure.
Steps
-
1
Calculate the volume
Measure the mould and run it through the resin calculator. Add the waste allowance before you decide how much to mix.
-
2
Prepare the workspace
Level surface, ventilation, gloves, and everything within reach. A pour cannot be paused halfway.
-
3
Measure the two parts
Measure part A and part B separately and accurately, using the ratio on the product data sheet. Mixing by eye is the single most common cause of resin that never cures.
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4
Mix thoroughly
Stir slowly for the full time the manufacturer specifies, scraping the sides and the bottom of the cup. Slow stirring for longer beats fast stirring.
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5
Colour and pour
Add pigment a drop at a time, then pour slowly into one corner of the mould and let the resin flow. Pouring into the corner reduces bubbles.
-
6
Cure and finish
Leave the mould level and covered for the full cure time on the data sheet, then demould and sand the edges if needed.
Skills you will practise
- volume calculation
- accurate two-part mixing
- pigmenting
- bubble management
- demoulding
If any of these are new to you, work them on scrap first. Practising a technique on the real piece is how an afternoon turns into a week.
Tips
- Warm the resin bottles slightly before mixing if the manufacturer allows it. Cold resin traps far more bubbles.
- Never top up a part-full cup with more of one part. If you are short, mix a fresh batch at the correct ratio.
- Keep the mould covered while it cures. Dust settles into tacky resin and cannot be removed afterwards.
Tools for this project
Work out the quantities before you buy anything. Each tool shows its formula and its assumptions.
Epoxy Volume Calculator
Compare what a mould or cavity holds against the pour you are planning, and see the shortfall or the surplus before you mix.
Mixing Ratio Calculator
Split a batch of resin into part A and part B for any ratio, by volume and by weight, with the percentage each part takes.
Mold Volume Calculator
Work out the volume of a silicone or wooden mould from its shape and dimensions, and how many millilitres of resin it holds.
Resin Calculator
Work out the millilitres and grams of mixed resin a mould needs, and split it into part A and part B at your ratio.
Resin Coating Calculator
Work out the resin volume and weight to coat a table top, a canvas or a small piece at a given thickness, per coat and in total.
Resin Cost Calculator
Total the resin, hardener, pigment, inclusions, mould and consumables for a project and see the cost of each piece.