GB2231306A

GB2231306A - Method of cutting letter box openings and a template therefor

Info

Publication number: GB2231306A
Application number: GB9007396A
Authority: GB
Inventors: Thomas Whitelaw
Original assignee: WHITELAW ALEXANDER
Current assignee: WHITELAW ALEXANDER
Priority date: 1989-04-11
Filing date: 1990-04-02
Publication date: 1990-11-14
Also published as: GB8908110D0; GB9007396D0

Abstract

A template 10 is provided for use in cutting out a letter box opening. It is a flat metal plate having a rectangular opening 11 therein to correspond to the dimensions of the letter box opening to be made. It also has two locating pins 13 extending from one face, one at each side of the opening and above these pins are two guide holes 13' to enable holes to be drilled in a door (12 Fig. 4) at the correct location to receive the locating pins. The pins 13 are hollow and the template is secured firmly to the inside of the door by screws which extend into the pins from the other side of the door. In use, a router cuts into the door guided by the edges of the opening 11. The router blade is set to a depth equal to half the thickness of the door and after that cut has been made, the blade is set to the full depth of the door and the cut completed to separate the cut out portion. The template is then removed and the letter box cover mounted on the door via the holes previously drilled to receive the locating pins. In an alternative method, after cutting a first groove from one side of the door, the template is removed and positioned on the opposite side of the door so that a second groove is cut from the opposite side of the door. <IMAGE>

Description

METHOD OF CUTTING LETTER BOX OPENINGS AND A TEMPLATE THEREFOR.

This invention relates to a method of cutting letter box openings and to a template therefor.

The usual method of cutting letter box openings is to drill holes at the four corners of the proposed opening and then sawing out the portion defined by the openings.

While this method provides the required opening, the neatness of the cut is dependent on the skill of the person using the saw.

An object of the invention is to provide a means of cutting out a letter box which is easier to do and gives a tidier finish.

According to one aspect of the present invention, there is provided a template having an opening therein corresponding to a letter box opening and a pair of locating pins extending from one face.

Preferably, the locating pins are hollow and have internal screw threading.

Preferably a pair of through holes are provided in the template corresponding to the spacing of the locating pins from each other. The through holes act as a guide for boring the holes in the work piece to receive the locating pins According to another aspect of the invention there is provided a method of cutting out a letter box opening in a work piece comprising securing a template to one surface of the work piece, said template having an opening therein corresponding to the dimensions of the required opening, and guiding a router (or like tool) along the edges of said template opening to cut into the work piece to separate the cut out portion from the work piece.

Preferably, the router is used to cut a groove to half the depth of the work piece and is then used to cut a second groove to complete the separation of the cut out portion.

Preferably also, the grooves are cut from the same side of the work piece, by controlling the length of the blade of the router so that it first cuts a groove to half the depth and then is extended so as to cut the second groove.

Alternatively, the template is positioned on the other side of the work piece after the first groove has been cut so that the second groove is cut from the opposite side of the work piece.

Preferably, the method includes the step of drilling two holes in the work piece at a pre-determined distance apart inserting locating pins of the template into said holes and securing the template firmly to the work piece.

Preferably also, the template is secured to the work piece by screwing a screw into each locating pin.

The work piece is usually a door but may be another part of a doorway.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is an elevation of a template according to the invention; Fig. 2 is a plan view of Fig. 1; Fig. 3 is a perspective view of the template; and Fig. 4 is a sectional side elevation of a work piece to which the template is secured.

Referring to the drawings, the template 10 is a flat thin metal plate having an opening 11 therein, the dimensions of the opening corresponding to the dimensions of a letter box opening to be made in a door 12. Thus the opening 11 is an elongate rectangle. For convenience, the external shape of the template is also an elongate rectangle.

Extending from one side of the template are two locating pins 13 one at each end of the opening 11. Each locating pin is hollow and internally threaded.

The locating pins may be firmly secured to the metal plate by suitable means, such as screwing or riveting.

The locating pins are spaced apart by a distance which is duplicated by a pair of through holes 13' drilled in the metal plate.

A spirit level (not shown) may be mounted on the template to ensure correct positioning on the work piece.

In use, the template forms a guide surface for a router to cut out the letter box opening.

Firstly two holes 14 are drilled in the door 12 at a predetermined distance apart so that the locating pins 13 locate therein. These holes 14 are drilled using the holes 13' of the template as a guide which ensures that the holes 14 are correctly spaced.

The template 10 is placed against one face 15 (the inner face) of the door with the pins 12 located in the holes 14. Screws 16 are screwed into the pins from the other side 17 of the door in order to securely fix the template 10. A washer 18 may be located against the door surface 17 if desired.

A router or like tool is then used to cut a rectangular groove 19 deep into the door, at least to half the thickness of the door.

This is done by setting the length of the router blade to half the depth of the door. When that groove 19 has been cut, the router blade can then be set to the fufll depth of the door and the groove 19 extended as 19' to complete the separation of the cut out portion. For a door of about 8 cm thickness, the time taken to cut out the letter box opening should be about 5 minutes. Any ragged edge to the opening will be on the outer surface of the door and will be covered by the letter box which is attached to the door, once the template has been removed, using the same holes 14.

In a modification of the method of forming and removing the cut out portion, the template 10, after the completion of groove 19 can be removed and fixed to the other side 17 of the door using the same drilled holes 14, then the router is used to cut into that side of the door until the rectangular cut out portion is severed from the door. The template is then removed and the drilled holes 14 are used to secure the letter box cover to the outside face of the door.

The resulting letter box opening formed using the template by above described methods has a neatly cut surface on at least the inside surface which is the visible surface and is accurately positioned.

Claims

1. A template having an opening therein corresponding to a letterbox opening and a pair of locating pins extending from one face.

2. A template as claimed in claim 1, in which the locatng pins are hollow and have internal screw threading.

3. A template as claimed in claim 1 or 2 in which a pair of through holes are provided in the template corresponding to the spacing of the locating pins from each other.

4. A method of cutting out a letter box opening in a work piece comprising securing a template to one surface of the work piece, said template having an opening therein corresponding to the dimensions of the required opening, and guiding a router (or like tool) along the edges of said template opening to cut into the work piece to separate the cut out portion from the work piece.

5. A method according to claim 4, wherein the router is used to cut a groove to half the depth of the work piece and is then used to cut a second groove to complete the separation of the cut out portion.

6. A method according to claim 5, wherein the grooves are cut from the same side of the work piece, by controlling the length of the blade of the router so that it first cuts a groove to half the depth and then is extended so as to cut the second groove.

7. A method according to claim 5, wherein the template is positioned on the other side of the work piece after the first groove has been cut so that the second groove is cut from the opposite side of the work piece.

8. A method according to any one of claims 4 to 7 which includes the step of drilling two holes in the work piece at a pre-determined distance apart inserting locating pins of the template into said holes and securing the template firmly to the work piece.

9. A method according to claim 8 wherein the template is secured to the work piece by screwing a screw into each locating pin.

10. A template substantially as hereinbefore described with reference to the accompanying drawings.

11. A method of cutting out a letter box opening in a work piece substantially as hereinbefore described.