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Compasses and Protractors . Compass. A compass (or pair of compasses ): a technical drawing instrument that can be used for inscribing circles or arcs. . Yes, there is another form of a compass which used for navigational purposes.
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Compass A compass (or pair of compasses): a technical drawing instrument that can be used for inscribing circles or arcs. Yes, there is another form of a compass which used for navigational purposes
An instrument with two arms, one sharp and one with a pencil that can be used to draw circles or arcs.
Circles can be made by fastening one leg of the compasses into the paper with the spike, putting the pencil on the paper, and moving the pencil around while keeping the hinge on the same angle. The radius of the circle can be adjusted by changing the angle of the hinge. Here is an example of a 30 degree angle:
Types and Cost Student Beam Compass $30-$40 Scribe Compass $15-$95 Loose Leg Wing $1 - $85 (dependent upon material)
Many Uses • Drafting • Mathematics • Finding radius • Duplicating circles • Arcs • Finding midpoint • Segmenting
Safety • These instruments were once a larger safety problem in the class • One end held the pen/pencil and the other was an extremely sharp point • Improvements have been made to decrease injuries and increase safety
Protractor Definition of Protractor Protractor is a tool used to measure angles. More about Protractor Some of the protractors are half circle protractors to measure angles up to 180° and some of them are full circle protractors to measure angles up to 360°.
Types and Cost Paper Printable FREE Bevel Protractor $40.00 - $380.00 Plastic Protractors $1 - $85 Most Common
SAFETY • Throwing • Sliding • Bending • Breaking
Diversity • Break angles in groups • See handout