Smart Tool System (STS)
Homebuilders and stone fabricators are seeing a steady increase in consumer demand
for more countertop profile options. The problem that this poses for stone fabricators
is that when exchanging one set of tools for another, the wrong set of tools can
be placed and tool information may not be updated properly. The results of such
mistakes are costly--damaged tools, damaged stone, and/or machine down time.
The Northwood 138-EDS and 158-EDS are equipped with standard 32-position tool storage
racks which provide the fabricator with storage space for four complete standard
tool profiles (bullnose, ogee, pencil edge, or seam) as well as finger bits, core
bits, a calibrating wheel, and a Z50 wheel. In response to the increased demand
for more profiles, Northwood Machine Manufacturing Company developed an innovative
solution for stone fabricators. The optional Smart Tool System (STS) is a modular,
automatic tool carousel and software program that provides a scalable, autonomous
system for the storage and delivery of tools to a machine tool spindle on a Northwood
CNC machine tool or router.
With STS, Northwood’s stone routers offer:
- infinite tools and profile set options
- quick and simple tool changes and job setups
- secure and efficient storage of tooling investments
- reduced chances of crashing the machine when swapping tools during processing
- no errors with cutting the wrong edge onto a countertop
The STS system includes detachable racks or carousels that can be stored offline
in a stand or cart; with each rack representing a tool profile set and containing
an automatic
means for home tool position recognition and automatic profile set
identification. STS provides offline tool setup and reduces the need for tool storage
space at the machine. STS also provides a substantially increased number of tool
positions over traditional rack or chain systems because an unlimited number
of profiles are possible per machining cycle with STS!
In addition to the multiple mechanical advantages, the STS system also includes
powerful software that provides automatic storage and retrieval of tool set information
and displays individual tool and/or tool set parameters relative to the corresponding
carousel or rack. STS offers seamless integration with tool measurement means and/or
digitizing for tool identification, drawing, adjusting for wear and/or matching
tool profile geometries, and for automatically applying various operational parameters.
Ergonomics
Northwood designed these machines with ergonomics in mind. When the machine completes
a program, the massive machine gantry retracts to the rear of the machine providing
total access to the machine's worktable. This provides the necessary clearances
for material lifting equipment as well as a clear view for the StoneLaser™ pod/part
location system. Even the water collection tank in the front was designed to serve
as a step to provide easier access for the machine operator for loading and unloading
the machine. In addition, Northwood’s revolutionary StoneScan™ barcode data input
system is seamlessly integrated into the machine's GE Fanuc control.
The machine's computer-designed frame structure is so rigid that the entire machine
can be lifted by a single (large) forklift and positioned in the shop. The massiveness
of the Northwood NW-158EDS and the 138EDS (Gen4) prohibits it from fitting into
a shipping container, which is the reason it is available only in the U.S.
StoneLaser™
The traditional approach to CNC stone machining has consisted of a very archaic
and time-consuming process using the machine tool to position part locator pins,
vacuum pods, and parts. The problem with this method is that it halts production
because the machine cannot produce while being set up.
Northwood engineers attacked this industry problem and developed the revolutionary
StoneLaser™ system, which automatically projects the layout pattern across the entire
work table. The machine operator simply positions the Blick vacuum pods and aligns
the blank material with the part geometry that is automatically projected by the
StoneLaser™.
StoneLaser™ reduces set-up times so much that up to 30% more countertops can be
produced per shift on the same machine. The outcome is very simple - Northwood CNC
stone machining centers produce more countertops per shift than the competitors'
do.
Warning! SuperZ Technology Can Damage Your Electrospindle!
Use SuperZ™ technology with your electospindle at your own risk. The EDS develops
its power at low RPMs because the motor windings have been designed to produce very
high torque at the RPM ranges customarily used to machine granite. In fact, the
spindle could be used for rigid tapping in steel!
Electrospindles for stone were derived from the glass industry, where higher RPMs
are required. As the spindle RPM's drop to the levels needed to machine granite,
the power output from the electrospindles drops off significantly. As long as you
are machining a homogenous granite (or engineered stone) material, feedrates can
be adjusted to control electrospindle loads to achieve acceptable feedrates. The
problem occurs when you try to machine granite materials with inconsistent densities
utilizing SuperZ™ technology on an electrospindle. The electrospindle can bog down
before the operator can take corrective action, and permanent damage the electrospindle
can result.
Because the EDS was based on machine tool technology, it has the ability to provide
very high torque levels at low RPMs so encountering hard spots with the SuperZ™
technology has little impact on the spindle.
Laser Tool Calibration System (LTC)
Tool Wear Leads to Development of LTC System:
Naturally occurring variability in stone material makes it difficult to maintain
the ideal tool relationships for any extended period. The idea tool set-up is temporary
and once changes start, tool tweaking results in wasted machine time. Northwood
developed a technology that periodically allows the machine to accurately measure
each tool and automatically make adjustments in the machine’s control for material
variability and tool wear variability. Northwood’s revolutionary LTC System employs
a very accurate laser beam to measure tool diameter dynamically. This provides a
measurement repeatability of +/- 0.0002” (or less) and totally eliminates the measurement
problems associated with water droplets.
Operational Simplicity
Northwood’s StoneScan barcode data input system controls the entire process. The
machine operator simply scans a barcode and the machine picks up the correct tool,
dynamically measures the tool’s diameter, calculates the actual tool wear, and updates
the machine control automatically. When the process is complete, the relationships
between each of the tools is then the same as when the perfect set-up was established!
Consumption Tools
Some tools wear at a much faster rate than others and require a slightly different
tool strategy to keep that perfect set-up. Both finger bits and resin polishers
(clay) wheels require such strategies.
Resin Polishers: The LTC System measures the tool and updates the machine control
so that the exact amount the tool has worn is compensated for – no more, no less.
This process eliminates the inaccuracies in polisher wear that accumulate as the
polisher is used repeatedly. Ultimately, significantly longer resin polisher life
is achieved.
Finger Bits: Finger bits produce a different consumption circumstance because of
the impact the actual tool wear has on each tool in the profile set. Each of the
abrasive wheels in the set has a specific depth of cut that is recommended . Finger
bits wear at a much faster rate than segmented wheels. As the finger bits wear,
the amount of material left for the segmented wheels to remove increases, which
has an impact on each succeeding diamond wheel. The LTC System overcomes this problem
by laser calibrating the finger bit each time it is placed in the tool changes.
This keeps the differential minimum for the segmented wheel always within the tooling
manufacturer’s specification. Great edge finishes and long tool life are the results.