WELCOME
FREQUENTLY ASKED QUESTIONS
STEPPERS VS SERVOS - which is better?
There is much debate on which type of system is "better" we at EZCNC can provide either type of drive
configuration with our machines so we don't have a bias in favor of one over the other.
Servos and steppers serve the same function - they make the machines move from point "A" to Point "B".
Up till recently there was a big difference between the two, servos were smoother, but advances in micro steeping
technology have eliminated this argument on high end stepper systems like EZCNC installs on all their machines.
While it is true that stepper motors can an do loose steps, this usually only occurs in low end or small frame motors
that are underpowered for the task. EZCNC uses large frame, high torque motors with industrial power
management and very robust driver packs to eliminate this problem.
Servo motors that are good quality (more about that later) are a joy when they work but can cause a big headache
when something goes wrong (and trust me - something will eventually go wrong, and usually at the most
inconvenience time) So, i only recommend them to folks that have experience with CNC systems and their
intricacies. Servo motors must be matched with the correct amplifier and need to be tuned.
Stepper motors are very simple motors that require virtually no maintenance. There is little the user can do to
damage them. They are very forgiving and good quality motors will generally last the life of the machine.
Servo -vs.- Stepper - How are they different?
Stepper motors are permanent magnetic motors that 'step' one increment each time the computer gives its control
electronics one pulse. They don't require position feed back if run within their limits. When stopped they inherently
hold their position.
Servo motors are standard DC or brush less motors with an encoder feedback loop. The computer reads the
position of the motor and controls the power applied to the motor.
Stepper motors generally are just as accurate as servos and are simpler and more reliable and maintenance free
in harsh dusty applications. The servomotor's encoder is susceptible to dirt and vibration causing problems.
Servo's are faster moving point to point and are better at accelerating very heavy machinery, but their higher
maintenance should be a factor in deciding which to go with. Our stepper motor system can be just as fast or
faster than many servo systems because of the control's software's algorithms.
Many companies that sell servo controls try to run steppers down. They don't know how good a properly made
stepper motor system can be! Our stepper systems never loose steps and can run for days with perfect
repeatability . A servo system with dust on the encoder will loose steps.
These are 2 servo motors from 4 x 8 machines.
The Servo on the left is what EZCNC uses, motor
on the right is from a competitor. Both are true servo motors, but there
are some big differences. The competitor shaft size is 1/8" vs 1/2 inch on
the EZCNC. Motor weighs 9lbs vs 1 lb. Torque is 1200 oz/in vs 87 oz/in.
Frame is made from 3/8" precision machined aluminum vs stamped steel.
The EZCNC motor has a very efficient winding design that actually uses less electricity than the competitors and
produces almost 14 times the output power. When comparing servo systems or stepper systems make sure that
you are comparing apples to apples.
What to look for: the better system manufactures will use NEMA 34 (or higher) frame motors with a multiple stack
configuration. Torque is very important to making a machine run fast, smooth and accurate. This is one place
where more power is better.
Porter Cable router Vs High Frequency spindle. Whats the difference?
We offer both Porter Cable routers and High Frequency spindles as the router bit tool holders. The main
difference between the two is noise and clamping power.
High frequency spindles are 3 phase induction motor that can run continuous duty and is designed for industrial
applications. Router bits are held very securely in a spring type ER collett. ER style tool holders apply very
uniformly distributed clamping on router bit an cause less breakage than Porter Cable type of colletts.
This type of motor should be considered if you have a production shop or where noise is a issue. Maintenance:
generally none other than keeping it clean.
Porter Cable routers are offered as a good and cost effective alternative to a industrial spindle. They are universal
brush motors that are much louder than a induction motor. We use Porter Cable routers over any other brand of
router because they hold up very well in a CBC environment. The Porter Cable speedmatic 3.25 hp. Router is
one of the best routers on the market and is a very good alternative to the Spindle with oversize thrust and axial
bearings near the base, middle and top of internal shaft, most users will get years of heavy use from this router.
Maintenance: Brushes need to be replaced as they wear down.
"Z" ZERO PLATE. Do I need one
Ezcnc routers are simple to set the "z" axis and don't require a zero plate. We have eliminated this item for two
reasons. 1. It's just another item that will eventually wear out or break, and Ezcnc tries to eliminate maintenance
issues. 2. They have a tendency to chip the delicate, sharp leading edge of your router bits. We will be happy to
provide one for you, but don't generally recommend them.
VACUUM TABLE. Do I need one
There are many ways to hold parts onto the table surface. If you will mostly be cutting parts out, you probably don't
need this feature, Break away tabs or a simple lead in and lead out will provide a satisfactory quality part in most
applications.
If you require precision engraving and exact cut of depth, or are doing high volume parts, than you will want to
consider this feature. For small shops and those who do not wish to take time needed to build dedicated spoil
boards (see picture below), simply holding your parts to the spoil board with a few screws is fine. Dedicated
vacuum spoil boards are the best and most accepted way of securely holding parts to a grid vacuum table. Our
standard 8 hp vacuum is good for this application. spoil boards made from ldf (light density fiber) can be used but
require much higher horsepower, typically 15-20 hp. Please be sure you have a electrical panel that can handle
high power loads before considering large vac. Pumps.
ROUTER BITS: what do i need.
With thousands of bit styles from dozens of manufactures available, EZCNC recommends purchasing bits
from companies that sell directly and understand CNC machines. A few ones we reccomend are, onsroud, vortex,
and Robb jack. Good quality, sharp carbide bits designed for the material you are cutting is essential to producing
a satisfactory cut quality. Many manufactures will guide you on proper speeds and feeds and their catalogs will
provide much useful information. Please note manufactures recommendations are only a starting point for setting
proper speeds and feeds. Each machine will require some tuning to find the best combination. In general, the
heavier the machine, the better the cut will be at high feed rates. Bit diameter is also very important, a good rule of
thumb is the wood you are cutting should not be more than 150% of the cutting diameter of the bit. For example:
1/4 dia. dit should not be used on material any thicker than 3/8 inch. Exceeding this limit will cause bit breakage.
EZCNC does not recommend the use of HSS bits for wood cutting as they tend to heat up quickly and dull fast with
the speeds and force that CNC machines can run at. There is 3 main categories of bits, upcut, downcut, and
straight cut. Down cut bits will push down on the wood and have a tendency to help hold parts down. They
expensive to sharpen. upcut bits will pull the wood up and should not Be used on our cnc systems. Straight bits
are the least expensive and most diverse category. In our opinion, bits that are manufactured in USA, Israel,
Korea, and japan tend to be the highest quality and longest lasting. We advise staying away from bits from China
as our experience has shown that the steel and carbide used just does not hold up well.
Maintaince: how much is required.
EZCNC systems feature the same precision bearings and linear guides that are found on very large industrial
systems. They are rugged and built for long life. EZCNC systems designed to be easy to maintain and do not
require a crew to keep them running well. The most important issue is lubrication. Bearings must be lubricated at
least once a week and if you work in a industrial shop, use it heavily, or do not have great dust collection; we
recommend greasing the bearings each day, this only takes a few min. And is easily accomplished with a standard
grease gun. Other than that, keep it clean. With a little preventative maintaince, the precession rails and bearings
will never need replacing. lack of lubrication will greatly affect the life of the rails and bearings. Grease helps keep
dust from getting into the bearings prevents them from seizing up.
I am thinking about a shopbot, why is EZCNC better?
EZCNC features industrial components that have a far greater life expectancy than those offered by shopbot.
EZCNC feature the same linear rails and bearings that are found on expensive Industrial machines. Our liner rails
have a rated life expectancy of 11,000 linear miles of travel with no significant wear. EZCNC gantry's are not a kit;
machines are shipped assembled and include a fully welded frame. EZCNC routers do not rely on springs to
support the "z" axis or hold motors in place. Springs eventually stretch and wear out.
If you are looking at the two systems, Please use the Alpha system when comparing pricing. Also Note the TOTAL
cost of the system, EZCNC includes the router, computer, full welded steel frame, and assembly. These are all
extra with the other system.
EZCNC
7005 Stoddard Lane
Plano, Texas 75025
(214) 924-0314
john@ezcnc.com
