If you find yourself needing to thin polyester resin for a project you are working on, a bit of acetone will do the trick. You may find yourself needing to thin the polyester resin for a variety of reasons. If you want the polyester resin to flow freely into cracks and crevices, you will need it to be thinner. There are a variety of brands available on the market, but unfortunately none may be the consistency you need. You want to make sure you are careful and take the proper precautions when using acetone to thin polyester resin because acetone can burn the skin.
In order to thin polyester resin with acetone, you will need:
- Polyester resin
- Stick to stir
- Be sure the polyester resin you choose to use is fresh. Don't use old resin laying around in your garage. Polyester resin is usually very inexpensive.
- Place your gloves on. Be sure to work in a ventilated area.
- Add the acetone to the polyester resin. The consistency you need depends on the project. For waterproofing wood, you are going to want the resin to be more of a liquid. In this case, you would need to add about four to six parts acetone for each part resin. You want it to be watery. For most other projects, you are going to use the opposite. Use one part acetone for every five to ten parts polyester resin. Stir the mixture.
- Once your polyester resin is the desired consistency, add the catalyst. Typically, you will need to use one ounce for every gallon of the diluted resin. Don't worry about having too much catalyst. This can be more of a problem when the polyester resin is not thinned.