GB2240743A

GB2240743A - Method of repairing rectangular window frames

Info

Publication number: GB2240743A
Application number: GB8928887A
Authority: GB
Inventors: Anthony John Hughes
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-12-21
Filing date: 1989-12-21
Publication date: 1991-08-14
Anticipated expiration: 2009-12-21
Also published as: GB8928887D0; GB2240743B

Abstract

A method of remaking a rectangular frame having a faulty edge member joined to the remainder of the frame by mitred corners comprises: providing a saw (22) positioned above a table for the frame and having a line of action at 45 DEG to a datum edge (21); offering up the faulty edge member to the datum edge, and moving the edge member lengthwise until the frame is positioned as required, relative to the cutting device; clamping the frame; moving the cutting device through its line of action to cut through the frame at one of the points where the faulty edge member is joined to the remainder of the frame; re-positioning the frame and re-clamping it, again moving the cutting device to cut through the frame at the or each other point where the edge member is joined to the frame; and fastening to the remainder of the frame a replacement member, in substitution for the detached member. <IMAGE>

Description

METHOD OF REPAIRING RECTANGU:IJAR FRAMES This invention relates to a method of repairing a rectangular frame.

It is a routine occurrence in the UPVC window fabrication industry for window units to be returned to the assembly site because, for one reason or another, they cannot be used. They might be of incorrect size, or damaged along one edge. After all, re-usable fittings have been salvaged, the frame itself is scrapped.

This invention aims to reduce the waste of otherwise useful units, by providing a method of using again not just the fittings but instead the whole unit, replacing only that element of it which is incorrect.

According to a first aspect of the present invention there is provided a method of remaking a rectangular frame with mitred corners and a faulty edge member, joined to the remainder of the frame at its two ends at least, the method comprising the steps of: i) providing a cutting device above a table for the frame, and a datum edge to which the faulty edge member may be offered up, the cutting device having a line of action at 450 to the datum edge; ii) offering up the faulty edge member to the datum edge, and moving the edge member lengthwise along the datum edge until the frame is positioned as required, relative to the cutting device; iii) clamping the frame in the required position; iv) moving the cutting device through its line of action to cut through the frame at one of the points where the faulty edge member is joined to the remainder of the frame;; v) re-positioning the frame on the table and re-clamping it there, then moving the cutting device once more through its line of action to cut through the frame at the or each other point where the faulty edge member is joined to the remainder of the frame; and vi) fastening to the remainder of the frame a replacement member, in substitution for the detached faulty edge member.

Conveniently, the cutting device is a radial arm saw.

The method is applicable to doors, but has its main application in window frames. It will operate with wooden or aluminium frames, for example, as well as uPVC.

With welded plastics frames, the cuts could be made through the welds for building a fresh frame of identical size, but the dimension of the frame perpendicular to the line of the faulty edge member can be reduced by selecting the line of action of the cutting edge to intersect the frame the appropriate distance back from the datum edge.

The table will normally carry a gauge for ensuring that the frame is so located, lengthwise of the datum edge, that the line of action of the cutting device is through the desired line on the frame members.

With welded uPVC frames, mullions and transom members are fixed to the frame members by a male/female "V" notch weld, with the frame members carrying the female parts of these joints. With the method of the invention, it is routine to prepare with the cutting device not only the mitre surfaces of the corners of the frame adjacent the edge to be replaced, but also the male "V" formation at the cantilever end of any mullion or transom member which is to be welded to the replacement frame edge member.

Further details of embodiments of the invention are apparent from the attached drawing figures 1 to 4 which are all plan views.

Figure 1 is a view of the male and female 450 "V" profiles of a frame edge member 10 and a mullion or transom member 11 at a joint 12 to be welded.

Figure 2 shows part of a frame 20 against a back stop (otherwise called "datum edge") 21. A radial arm saw blade 22 at 450 to the edge 21 makes cuts in the frame 20 along a line of action 23. A point P is marked on the frame 20 where the cut is required, and distance B is measured, to the rear face of the edge 21. The frame is set a distance A from the blade 22, where A = B, using an adjustable gauge and stop 24. With the frame 20 so positioned, it is clamped using a pneumatic clamp 25.

Figure 3 shows the same rig but with the frame 20 reversed for making the second cut to form a male "V" formation on the cross-piece 26 of the frame.

Figure 4 shows use of the same technique for preparation of a corner mitre on a frame, with a frame to be re-made slightly narrower (in the direction perpendicular to the datum edge 21) than the original frame.

In another embodiment, the male "V" formation on any frame member intermediate the ends of the frame can be created in one cutting operation by the action of a cutting unit which comprises two devices with lines of action at 900 to each other.

Claims

1. A method of remaking a rectangular frame with mitred cornors and a faulty edge member, joined to the remainder of the frame at its two ends at least, the method comprising the steps of: i) providing a cutting device above a table for the frame, and a datum edge to which the faulty edge member may be offered up, the cutting device having a line of action at 452 to the datum edge; ii) offering up the faulty edge member to the datum edge, and moving the edge member lengthwise along the datum edge until the frame is positioned as required, relative to the cutting device; iii) clamping the frame in the required position; iv) moving the cutting device through its line of action to cut through the frame at one of the points where the faulty edge member is joined to the remainder of the frame:: v) re-positioning the frame on the table and re-clamping it there, then moving the cutting device once more through its line of action to cut through the frame at the or each other point where the faulty edge member is joined to the remainder of the frame; and vi) fastening to the remainder of the frame a replacement member, in substitution for the detached faulty edge member.

2. A method according to claim 1, comprising the step of selecting, as the cutting device, a radial arm saw.

3. A method according to claim 1 or 2 wherein the frame is a window frame.

4. A method according to claim 1, 2 or 3 wherein the frame is a welded plastics frame.

5. A method according to claim 4 wherein the cut ale through the welds for building a fresh frame of idenicl size

6. A method according to any one of claims 1 to 4 including the step of selecting the line of action of the cutting edge to intersect the frame a distance back from the datum edge appropriate to reduce by a desired amount the dimension of the frame perpendicular to the line of the faulty edge member.

7. A method according to any one of the perceding claims including the step of providing with the table a gauge for ensuring that the frame is so located, lengthwise of the datum edge, that the line of action of the cutting device is through the desired line on the frame members.

8. A method according to any one of the preceding claims, in which the frame is a welded uPVC frame, having mullions and transom members fixed to the frame members by a male/female "V" notch weld, with the frame members carrying the female parts of these joints, and comprising the step of preparing with the cutting device not only the mitre surfaces of the corners of the frame adjacent the edge to be replaced, but also the male "Vl' formation at the cantilever end of any mullion or transom member which is to be welded to the replacement frame edge member.

9. A method of reparing a rectangular frame substantially as hereinbefore described with reference to the accompanying drawings.