How to prepare

Good preparation prevents most resin problems before they start — bubbles, dust, uneven cure, and wasted material usually trace back to the room or the workspace, not the resin itself. This guide covers what to check before you mix: room conditions, your work area, and the gear you need on hand.

Ideal working conditions by product

Room temperature and humidity affect cure quality more than almost anything else. Check these before you start:

Product	Ideal room temperature	Maximum humidity	Notes
Arts & Crafts	24-30°C	85% RH
Table Top	25-30°C	70% RH	Most humidity-sensitive product in the range
Deep Pour	22-25°C (1-5kg batch), 20-23°C (5-10kg), 18-21°C (10-20kg), below 18°C (over 20kg)	85% RH	Cures exothermically — larger batches need a cooler room
UV Resin	Not specified — cures under a UV lamp, not by ambient temperature	Not specified	Single component, no mixing involved
Silicone (mould making)	Tested at 25°C	Not specified	1:1 by weight

If your room runs colder than this, don't compensate by adding more hardener — that throws off the ratio and won't fix a cold cure. Warm the room, or warm the resin itself (see below).

Setting up your space

Clear and clean the surface. Dust, hair, and debris are the most common cause of specks and craters in a cured piece. Wipe your table down before you bring the resin bottles out.

Cover what you're not willing to sand. Plastic sheeting or a disposable liner under your work protects the surface underneath — resin that drips onto an uncovered table is much harder to remove once it cures than while it's still wet.

Keep everything within reach. Have your mixing cups, stir sticks, torch or heat gun (for coating layers only), and level all set out before you start mixing. Once resin and hardener are combined, the clock on your working time is running, and stopping to find a tool costs you minutes you don't have.

Check that your surface is level. An unlevel pour cures unlevel — there's no fixing it afterward without sanding and recoating.

Warm cold resin before you mix. Below 15°C, warm Part A (the resin) to around 30°C before combining it with hardener. Cold resin is thicker, traps more air, and can slow or unevenly cure.

Why conditions matter

Room temperature and humidity aren't just comfort issues — they affect the chemical reaction directly. A cold room slows the cure and can leave a piece soft well past its expected time. High humidity can pull moisture into the mix while it's still curing, which is a common cause of a cloudy or hazy surface. On the other end, mixing a larger batch than the working time allows for means the resin can start to set before you've finished pouring — bigger batches give you less working time, not more, because the exothermic reaction builds heat faster in a larger mass.

None of this is about getting a "perfect" result on the first attempt — small variations in humidity or a slightly cool workshop are a normal part of working with resin, and most of them are recoverable. Preparation just narrows the range of things that can go wrong.

Step-by-step

1. Check the room. Confirm the temperature and humidity against the table above for the product you're using, and adjust with a heater, air conditioner, or dehumidifier if needed.
2. Clear, clean, and level your workspace. Remove dust and debris, cover surfaces you don't want resin on, and confirm your project surface is level.
3. Gather your PPE and tools. Disposable gloves, an apron, and (if you have long hair) something to tie it back are worth putting on before you open the bottles, not after a spill.
4. Warm the resin if the room is cold. Below 15°C, bring Part A up to about 30°C before mixing.
5. Measure your batch to match your working time. Don't mix more than you can pour within the product's working time — mix smaller batches in succession for larger projects instead of one oversized batch.

Related articles

• Mixing Ratio — How to Measure Resin and Hardener Correctly
• Sticky or Soft Result — Troubleshooting Incomplete Cure
• How to measure your craft resin