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Phone: 516-328-3970
www.technocnc.com
Technical Section
Collet Maintenance
Tool geometry, cutting material, and machine feeds and
speeds are all important to the machine’s performance.
Basic tooling maintenance should be at the top of this list.
Proper colleting and collet maintenance are essential, and
directly affects the cut quality and longevity of the spindle.
A clean collet, tool holder, router bit, and spindle taper
allows for a firm grip of the tool, preventing tool runout.
“Runout” occurs when the tool and spindle do not share the
same center of rotation (they are not concentric). This
runout puts enormous strain on the spindle bearings and
can cause the spindle to fail prematurely. In addition, a tool
that is not perfectly concentric will result in an uneven, wavy
cut. It is recommended that the collet, tool holder, router bit,
and spindle taper be cleaned each and every time you
change a tool. When the machine is running, dust and
debris collects in all crevices of the spindle, while resins can
build up on the tooling. These resins will usually build up
around the mouth of the collet. Because of this buildup, the
tool may not be properly gripped, and a loss of concentricity
(“runout”) of the tool results. Proper cleaning and
maintenance easily solves this problem.
Spindle Taper
Proper maintenance for optimal performance does not
stop at the tool or the tooling accessories. Care should be
taken to extend cleaning to the spindle as well. For instance,
regular cleaning of the inside of the spindle taper should be
part of your maintenance regimen. In addition, always
leave a tool holder in the spindle, even when the machine
is not in operation. This will greatly reduce the amount of
dust and debris that can enter the spindle’s interior,
subsequently causing premature spindle failure.
Vacuum Hold-Down
The most common
question asked when it
comes to vacuum hold-
downishowmuchvacuum
does my application
require? Vacuum systems
should be evaluated
based on the specific
applications. The smaller
the part or thinner the
material to be held, the
greater the volume of air
flow required, thus
increasing the size of the
vacuum pump. Many
people state that you can’t have enough vacuum. This is
somewhat a true statement. However, it can be a very
costly fact. It is always easy to overbuy. Purchasing a single
40HP or 50HP pump can cost in excess of $25,000, and the
purchase is only the initial cost. Depending on where your
shop is located, the utility rates can vary considerably.
Keep in mind that operating costs (utility) rarely go down, so
these costs will increase year to year.
Purchasing a number of smaller pumps can help reduce
the price of the pump as well as reduce the overhead to run
these pumps. If you are processing sheets of materials that
have large parts, then a single pump can be utilized. If the
nest has numerous smaller parts, then it is best to run all the
pumps for maximum air flow.
There are other devices
