How To: Use A Mitre Box

  • 1 There are two different types of Mitre Box available. A plastic version and a wood version.
  • 2 A Tenon Saw with its fine teeth is ideal for precision woodworking and is best suited for a Mitre Box.
  • 3 There are slots on the mitre box which allow you to cut at 45-degree or a 90-degree angles
  • 4 Attaching the mitre box to your Workmate will give you added stability when you are sawing.
  • 5 Skirting: When cutting an internal corner for a piece of skirting you need to make the following cuts. For the left hand piece of an internal corner you place the skirting in the mitre box with the wall side of the skirting against the side of the box furthest away from you and simply cut a 45degree angle from the bottom left to top right.
  • 6 When Cutting the right hand piece of an internal corner you place the skirting in the mitre box with the wall side of the skirting against the side of the box furthest away from you and simply cut a 45degree angle from the bottom right to top left.
  • 7 This is what your internal corner should look like.
  • 8 When cutting an external corner for a piece of skirting you need to make the following cuts. For the left hand piece of the external corner, you place the skirting in the mitre box with the wall side of the skirting against the side of the box furthest away from you and simply cut a 45degree angle from bottom right to top left.
  • 9 For the right hand piece of the external corner, you place the skirting in the mitre box with the wall side of the skirting against the side of the box furthest away from you and simply cut a 45degree angle from bottom left to the top right.
  • 10 This is what your external corner should look like.
  • 11 When joining two pieces of skirting together in length, place the first piece of skirting in the mitre box with the wall side of the skirting against the side of the box furthest away from you and simply cut from bottom left to top right. Make the same cut on the second piece skirting.
  • 12 This is what the join should look like.
  • 13 Cutting Coving: When cutting an internal corner for a piece of coving you need to make the following cuts. For the left hand piece, you place the coving in the left hand side of the box with the wall edge of the coving sitting against the mitre box side closest to you and the ceiling edge of the coving against the base of the box. Simply cut at a 45degree angle from bottom right to top left.
  • 14 For the right hand piece, you place the coving in the right hand side of the box with the wall edge of the coving sitting against the mitre box side closest to you and the ceiling edge of the coving against the base of the box. Simply cut at a 45degree angle from bottom left to top right.
  • 15 This is what an internal corner should look like. On an internal corner the wall edge is always the longest side of the mitre.
  • 16 Or when cutting an External corner for a piece of coving you need to make the following cuts. For the left hand piece, you place the coving in the left hand side of the box with the wall edge of the coving sitting against the mitre box side closest to you and the ceiling edge of the coving against the base of the box. Simply cut at a 45degree angle from bottom left to top right.
  • 17 For the right hand piece, you place the coving in the right hand side of the box with the wall edge of the coving sitting against the mitre box side closest to you and the ceiling edge of the coving against the base of the box. Simply cut at a 45degree angle from bottom right to top left.
  • 18 This is what an external corner should look like. On an external corner the wall edge is always the shortest side of the mitre.
  • 19 When cutting a joining piece of coving for the left hand side simply put the left hand piece in the left hand side, making sure the Wall side of coving is against the side of the box closest to you and the ceiling side of the coving is at the bottom of the box and cut left to right.
  • 20 When cutting a joining piece of coving for the right hand side simply put the right hand piece in the right hand side, making sure the Wall side of coving is against the side of the box closest to you and the ceiling side of the coving is at the bottom of the box and again cut left to right.
  • 21 This is what a mitre joint should look like.