A set square or triangle is an object used in engineering and technical drawing, with the aim of providing a straight edge at a right angle or other particular planar angle to a baseline.
Ways of maintaining set square;
1. You have to handle your set square softly and with accuracy without exercising too much pressure on them, only the needed one to avoid movement.
2. Don’t use the T-square as a hammer - or an axe!
3. Don’t let the T-square fall on the floor.