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Picture Frame

Problem

A photograph measuring 12" times 16" is to be mounted in a frame in the following way.

What length of frame material will be needed to construct the frame?


Solution

The finished frame will be 3/4" larger than the photograph at each edge. Hence the external dimensions of the frame will be 13.5" times 17.5".

If the frame material had a simple rectangular cross-section cut we could alternate directions to use less material, but this type of frame has a recess on one side for the picture to slide in to, so it is necessary to make cuts in the following way.

Hence the minimum length required for the photograph will be 17.5 + 17.5 + 13.5 + 13.5 = 62".

However, when making picture frames it is alway a good idea to allow an additional 1/8" both vertically and horizontally in the recess to give the picture room to be seated properly. Also the width of the saw cut should be taken into account.

By allowing for the additional room and assuming that the saw removes 1/8" of material with each cut, what length of frame material should be used?

Problem ID: 308 (04 Feb 2007)     Difficulty: 1 Star

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