What Can You Cut With a Hotknife?

Item # X-HT-300090

A question we get asked a lot around here at Sailrite is “What can I cut with my hotknife?” We thought that we’d not only answer that question for you, but also give a little demonstration of things that cut nicely, and what happens when you cut something that is not recommended.

Cutting Sunbrella with a hotknife

As a general rule of thumb, if the material is synthetic (man-made) then it will cut well with a hotknife. Examples of synthetic fabrics include acrylic, polyester, nylon and polyolefin. If it is a natural material it will not. Natural fabrics don’t have any material that will melt with the heat and, therefore, they tend to burn. Natural fibers including cotton, linen and bamboo should be cut with scissors.

However, there are exceptions to this rule. For example, vinyl is a synthetic material, but cutting it with a hotknife is not a good idea. The hotknife melts the vinyl, leaving an unsightly edge (not to mention that melting vinyl smells terrible!). Fabrics like Sunbrella® SeaMark® that are acrylic with a vinyl backing can be cut with scissors without the material unraveling. Morbern®, Stamoid™, Naugahyde® and Ultraleather® are other fabric brands that should be cut with scissors.

Take a look at our roundup of materials that work well with a hotknife and some that don’t.

Top 7 Materials to Cut With a Hotknife:

  • Acrylic Fabrics (like Sunbrella® Marine and Upholstery fabrics)
  • Polyester Fabrics
  • Nylon Fabrics
  • Dacron® Sailcloth
  • Synthetic Webbing
  • Synthetic Rope
  • Zippers

4 Materials to Avoid Cutting With a Hotknife:

  • Cotton
  • Cotton Blends
  • Vinyl
  • Leather

Sailrite® Hotknives

We have two versions of our best-selling Sailrite® Edge Hotknife. The original Edge is a corded version, and the Edge Cordless is our cordless hotknife. The cordless version comes with two rechargeable lithium-ion batteries. Both of our hotknives perform perfectly and cut synthetic materials with ease, but if you need the ultimate mobility of a cordless hotknife, we recommend the Edge Cordless.

Did you know you can't use a hotknife on just any surface? The heat from the blade will damage and scar tables and floors. You need to place a sacrificial surface beneath your fabric, webbing or rope to protect both the surface and your blade. The Tempered Cutting Glass for Hotknife, available only at Sailrite, is the perfect companion to your hotknife. It protects your table or work surface, and its size enables long, precise cutting. Tempered glass is a type of safety glass that has been manufactured to be stronger than regular glass. If the glass were to break, it would crumble into small chunks instead of splintering into jagged, dangerous shards as normal glass does, thus making it safer to use and keep in your work area than normal plate glass.

Now you can make an informed decision before using your hotknife during your next project! What do you use your hotknife on most often? Share your experiences in the comments!


This blog was updated in May 2020 to reflect new products and recommendations.