How to cut polyurethane foam

One of the most common closed-cell foams, polyethylene has numerous densities which affect cell size, firmness, and flexibility. In its lowest densities, it has a fairly large and bubbly cell structure, which can impact how clean a cutting edge is. Because of this, we suggest against using scissors to cut polyethylene.

Foam Cutting Tools

Hot wire foam cutters are the fastest, cleanest and easiest tools to use to cut rigid polystyrene foams, like Styrofoam, white beaded EPS, and XPS foams (blue and pink board). The hot wire tools slice through foam like a hot knife through butter, melting Styrofoam to leave a clean cut behind.

Cutting Polyurethane Parts​

One of the best machines for cutting urethane parts is a band saw. Long blades of 125 to 175 inches (3,175 to 4,445 mm) are desirable because they stay cooler and keep the urethane from melting. A band type we have found to work well is a 4 tooth per inch with raker set.

Some forms of synthetic leather are made using polyvinyl chloride (PVC), polyurethane, or other plastics that create hazardous gases when laser cut (see potentially hazardous materials section) and SHOULD BE AVOIDED.

There are advantages to using a polyurethane molding. For instance, it can be installed by one person, does not need time to acclimate in a room before installation and can be cut quickly with a handsaw and miter box.

A: Polyurethane foam should not be cut with hot wire tools. It needs a ton of heat, gives off toxic fumes, and leaves a lot of melted plastic wherever it is cut. We recommend that the polyurethane foams only be cut with a blade or saw.

Polyurethane (PUR and PU) is a polymer composed of organic units joined by carbamate (urethane) links. While most polyurethanes are thermosetting polymers that do not melt when heated, thermoplastic polyurethanes are also available.

Durability. Polyurethane has exceptional abrasion and tear-resistance, typically better than rubber. It also has increasing load-bearing capacity, impact-resistance, and excellent wear properties.

Polyisocyanurate foams have excellent insulating value, good compressive-strength properties, and temperature resistance up to 300 degrees F. They are made in high volumes at densities between 1.8 and 6 lbs per cubic foot, and are reasonably inexpensive.

There is no difference between the terms urethane and polyurethane. The term polyurethane simply means that it contains multiple urethane groups. Polyurethane elastomers (urethane elastomers) are one type of a large family of elastic polymers called rubber.

Urethane is flexible and malleable, making it ideal for objects that have different shapes and forms, and it is used in liquid form. Polyurethane, on the other hand, is stiff and rigid and is ideal for firmer items, with many advantages over natural rubber.

Because polyurethane is stiff and hard, they are mostly used in solid materials such as foot wears, foams, etc. Although polyurethanes are harder and have better wear tendencies than urethanes, they are usually used for indoor furniture and products instead of outdoor ones.

Polyurethane is the most durable of clear exterior finishes. Polyurethane can be used successfully outdoors if it has the proper ingredients. Look for a finish that has additives for ultraviolet protection. The label should say for exterior use so the dried finish will flex with the expanding and contracting wood.

The Best Non–Yellowing Water-Based Polyurethane

The best non–yellowing clear coat is Minwax’s Polycrylic. It’s easy to use, dries within a few hours, can be applied multiple times within 24 hours, dries completely clear, and doesn’t yellow over time.

Minwax® Helmsman® Spar Urethane is specially formulated as a protective clear finish for exterior or interior wood exposed to sunlight, water, or temperature changes. Contains UV blockers to reduce the sun’s graying and fading effects. Forms a protective barrier against rain and moisture.