3D CNC Systems

Well, I have been considering an inexpensive (LOL!) CNC Milling
system. I would like to hear anyones comments with regards to the

	Taig Mill

Sherline is soon to release a full turn-key 3 or 4 axis CNC system.
I have built two Sherline 4-axis CNC mills and could not be happier
with their performance.

Daniel J. Statman, Statman Designs

I Have been using the Taig MicroMill 2000HD/LE for over a year now
and am extremely satisfied with it. I use Rhyno for my designs,
export them to Bob-Cad to generate the machine code, then export the
machine code to a program supplied by Micro Proto Systems (mps2000)
Most of my work can be done without using solid geometry.

I also have Desk Proto. I think it is over rated. If you’re using
the forth axis, Desk Proto will take many hours to carve a ring. It
is much quicker to mill out the ring size in a wax tube and then cut
only the upper half of the ring out of the top of the tube. It takes
only a few minutes to carve the back of the ring by hand to finish
up. If I were to buy it again I would buy the lite version. You
don’t need to be a rocket scientist to do two sided milling. If you
buy this system you might want to keep a record of my e- mail. If you
run into problems, I might be able to help. My first two weeks with
the machine were a nightmare. It turned out that a nut was loose on
one of the drive screws introducing a large error in the y-axis.

R hood

Taig Mill

These are really heavy-duty mills for the size (12"X, 5.5"Y, 6"Z for
the LE model. They come with an open-loop stepper system that limits
their working feedrate to 20 ipm, but they will keep going for a long
time without problems. The spindle is controlled by a continuous-duty
AC motor, and can be set for high torque and low speed, which is good
for metals like steel. The company offers a 2-year warranty on its
products, and tech support is good. The price (list is $2195) is
excellent considering how well-built the machine is, and dealers
(like me) offer additional discounts.


These all-aluminum mills are lighter-duty and less rigid than the
Taigs, but offer several features they lack. The cheaper models are
open-loop and very slow (6 or 12 ipm) but the more expensive
closed-loop models are faster than the Taig, and use encoders on the
stepper motors that monitor motor position and help avoid lost steps.
They also use anti-backlash nuts, which is good except that their
plastic parts tend to fail in use. They use 10k rpm Dayton spindle
motors which tend to burn up after a few months of use, and which
cause servo errors when their brushes arc. The spindles are
speed-controlled in software, which is convenient, although torque
at low speeds isn’t high. MaxNC offers a 1-year warranty, their tech
support is spotty, and getting satisfactory customer service can be

Roland MDX-15/20

These are combination scanner/mills that fill a unique niche,
especially for people more adept at sculpting in clay or wax than on
a computer. The scanning function is strong, and the fine
piezo-electric needle probe is able to capture fine detail. One can
make a part in a soft material like plasticine clay, and scale it up
or down, or create a left part from a right. The milling function is
obtained by swapping a small self-contained spindle assembly for the
probe unit. This is a very light-duty spindle, suitable for carving
wax but not much harder materials. Another drawback is the lack of
tee-slots in the table, so holding a part down to the bed is
difficult, although fixtures can be screwed down to it. And the
small amount of head-room makes a 4th axis attachment (available for
the Taig, MaxNC and Sherline mills) unfeasible. But on the positive
side, they come with a suite of software that makes the scanning
function work, and enables one to do basic milling and engraving as
well. List price for the MDX-15 is $2995; the larger MDX-20 lists for
$4495, but discounts from dealers (like myself) can reduce that

I should also add the Sherline mill to this list- they have just
announced that they will soon be offering a CNC-equipped version of
their popular mills, which will come with its own dedicated computer
with EMC (a machine control program operating in Linux) preloaded.
Their spindle motor is the best of the bunch considered heRe: a
half-horse DC motor with variable speed up to 3k rpm. (which makes
the spindle go at speeds up to 10k rpm.) It will be selling for about
$2400, with further discounts possible from dealers.]

Andrew Werby

Hi Mike,

I don’t have experience with the mills you mentioned, so my comments
are only intended to be things to be aware of, in general. With the
substantial investment in a CNC mill, a comparision of milling
accuracy is really important. Ask for samples of one of your more
intricately detailed SolidWorks models to be made, so you can see and
compare a level of accuracy related to your design needs. Precise and
clean milling of text on modulated surfaces is a good test. The CAM
software must be designed to negotiate this accuracy, so be sure you
are getting the same CAM package used to make the sample. Ask about
training and tech support, as well as if CAM software is included.
Price is often associated with quality of parts & how well they
fit/work together.

Lower end machines may have a certain amount of “backlash”. A hobbist
level mill can be a money pit to retrofit in order to produce a
workable model, so it’s good that you’re doing this research!

Best regards,
Jesse Kaufman
CAD/CAM Technology
Handcrafted Originality

So, I take it that you are saying that perhaps I should wait till
the Sherline comes out with their CNC packages if I want the best?
Also, out of the Taig and the Sherline, which comes with the best
software? I currently use Solidworks, but I don’t have a
g-code/toolpath generator for it. I can of corse output to an iges
or other file, but I need something to translate from there. It
would be nice if the software was bundled with the package.