How To Use A Utility Knife To Trim Picture Framing Mat Boards

Utility Knives or Stanley Knives are the most dangerous tools you will use when you’re framing pictures. More people cut themselves with one of these types of knives than they do on a saw or when cutting glass or many other things. When you’re using a snap off knife or a Stanley type knife, be very careful and make sure to keep a sharp edge.

Always keep a nice sharp blade tip because then you can be confident you are going to cut the board a lot better than when it is blunt.

NOTE: Blunt knives tend to slip and they cause a lot of damage, they will still cut your fingers but they won’t cut as well through the board.

The other thing about a craft knife is that it is sharp on the bottom. Even though it has got a little pointy bit at the tip which is a sharp point it is actually the bottom of the knife that does the work when cutting. If you have the knife on a steep angle when you’re cutting then you’re not presenting much of that sharp blade so you really want to lay the knife down on a flatter angle and that way it is easier to cut the mat board.

You need to have a scrap piece of board, an off-cut to put down on the table you’re working on and you put your board on top when cutting. That way when you’re actually cutting this board, you’re not going to cut your table and you are going to protect the board you’re working on.

NOTE: It is important that everything is kept clean in picture framing. If it’s dirty you are going to end up with a bad job, so keep everything clean.

Now the ruler you should be using usually has a rubber backing and a bevelled edge with the measurements on. I always like to think of having 2 sides to them. They have a measuring side which we use to measure things up and they have got a thick back edge. The thick back edge is the side we use to cut along. It’s not just because the ruler is thicker at the back edge and it can stop you slipping that you should use it for cutting along. It is because if you cut down the measuring side of your ruler, your ruler will gradually become curved from where you’ve been cutting all the time. Over the years, if you want your rulers to last, cut on the back edge where it doesn’t matter if it gets worn and keep the measuring side for measuring only.

Put the back side of the ruler on the line that you want to cut and put it on the side of the board where it covers the piece you want to keep because if you’ve covered the piece you want to keep and if by chance you slipped off the line, you will cut into the waste of the board and not the good piece of board that you want to keep. Lock your knife in place and then make sure that your ruler is accurately on the line. Make sure you hold the ruler firmly.

The amount of pressure that you need to use to cut the outside size of the mat board is very minimal. Remember you don’t have to cut through the board in one go, but when you use gentle pressure you minimise the risk of slipping or cutting yourself. All you need to do is keep hold of the ruler and go over the line again and again. Each time you trim, remember to keep the knife lent over so you are using a lot of the cutting surface. It might take a few passes to cut all the way through.

Take care when cutting with a Craft or Utility knife because when used incorrectly or casually it is easy to cut yourself.

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