Desa 496 Drill User Manual


 
12
105635
Why A Power Fastener Holds
WHY A POWER FASTENER HOLDS
IN CONCRETE
The compression bond of the concrete to the power
fastener accounts for the majority of the holding power.
The fastener displaces the concrete which tries to return
to its original form causing a squeezing effect.
Maximum holding power is achieved when the depth of
penetration produces a bond on the power fastener equal
to the strength of the concrete. As a general rule, pene-
tration should be approximately 1" to 1 1/4" into the base
concrete. Make sure the concrete is at least three times
as thick as the intended fastener penetration. Never have
the power fastener point protrude through the concrete.
NOTE: Concrete needs to cure for 28 days before
maximum fastening holding power will be achieved.
WHY A POWER FASTENER HOLDS IN STEEL
Holding power in steel depends on the elasticity of the
steel. The steel pushes back on the shank of the power
fastener.
Drop a marble into water; the water parts, the marble
continues down, the water closes back. This is similar to
the reaction when a power fastener penetrates steel.
In steel, the point of the power fastener must penetrate
completely through for highest holding power. If the
fastener does not penetrate, the spring action of the steel
pushes back on the point and tends to force the fastener
out.
Recommended applications are between 3/16-3/8"
steel.
NOTE: When fastening in steel be sure the point goes
through the steel.
482-64
482-65