Cutting Hardie Backer Made Simple, Using a Utility Knife, Key Is To Pull Toward You

I've seen many people use power tools to cut hardie backer board. In this video you'll see how easy it is to use basic tools to cut hardie backer with very nice accuracy. It is quick, easy & accurate.

[@jonathanwebb9862]

I watched this and thought 'great'. Scored my 12mm board far more than the 4 or so passes, but can I snap it? Lol. Even with my weight plus a small jump it's not interested in snapping. Going outside to use the grinder now...

[@JustForYouDiy]

If the pieces you’re cutting are less than 3” wide, using this method is challenging, especially with 1/2” thick hardie.

[@jonathanwebb9862]

@@JustForYouDiy I deliberately allowed 150mm to get some leverage. AIUI the Hardi knife cuts a V groove. I gave it one last go, angling the knife a bit on the waste side to make a bit of a V and it worked. Although the break isn't as smooth as I'd like. I'll do the next two (only got 3 boards) with the grinder - that's a piece of cake, just messy.

[@JustForYouDiy]

Perfect. I hardly use the angle grinder for that same reason, too messy. You can also cut holes this way, scoring with knife then using a hammer.

[@evepaludan7713]

Thank you!

[@JustForYouDiy]

My pleasure.

[@johngreen4200]

How do you cut straight freehand? I wander out no matter how slow or patient I try.

[@JustForYouDiy]

The key is in the deep scoring with the knife. If the scoring is good, the cut comes out straight. Hope this helps.

[@BenMargolin]

using good form (stay vertically "on top" of the cut, move fluidly and letting the tool do as much of the work as possible) and practice is the true answer.