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How to check right angles with a folding square

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Carpenters square, folding squares, carpenter, carpentry, angles, woodwork, measuring, framing, right angle, stone masonry, building, construction, flooring, paving, DIYer. In this section the laying of tiles will be used as an example of when you may need to check right angles.
Carpenters square, folding squares, carpenter, carpentry, angles, woodwork, measuring, framing, right angle, stone masonry, building, construction, flooring, paving, DIYer.

Step 1 – Find right angle

Locate the 90° angle (right angle) on the folding square.

Carpenters square, folding squares, carpenter, carpentry, angles, woodwork, measuring, framing, right angle, stone masonry, building, construction, flooring, paving, DIYer.

Step 2 – Position folding square

Place the corner of the 90° angle (right angle), against the corner you are checking.

Carpenters square, folding squares, carpenter, carpentry, angles, woodwork, measuring, framing, right angle, stone masonry, building, construction, flooring, paving, DIYer.

Step 3 – Line up folding square

Push the corner of the folding square (90° angle) firmly against the corner of the tiles.

Carpenters square, folding squares, carpenter, carpentry, angles, woodwork, measuring, framing, right angle, stone masonry, building, construction, flooring, paving, DIYer.

Step 4 – Check work

Check if the sides of the folding square are flush against either side of the tiles.

Here, the term ‘flush’ essentially means that there will be no gap on either side of the square, with the right angled edges fitting perfectly.

Carpenters square, folding squares, carpenter, carpentry, angles, woodwork, measuring, framing, right angle, stone masonry, building, construction, flooring, paving, DIYer. If each side is flush against the corner, then it’s a 90° angle (right angle).
Carpenters square, folding squares, carpenter, carpentry, angles, woodwork, measuring, framing, right angle, stone masonry, building, construction, flooring, paving, DIYer. If there is a gap between the sides of the folding square and the sides of the tiles then it is not a right angle.

This can be a result of the tiles not being cut correctly or of the edge where you started laying tiles not being straight.

Wonkee Donkee says, "This is only an example of checking a right angle using a folding square. The folding square can be used on a number of different applications."