Direct Numerical Control, also known as Distributed Numerical Control,
(both DNC) is a common manufacturing term for networking CNC machine
tools. On some CNC machine controllers, the available memory is too
small to contain the machining program (for example machining complex
surfaces), so in this case the program is stored in a separate computer
and sent Direct to the machine, one block at a time. If the computer is
connected to a number of machines it can Distribute programs to
different machines as required. Usually, the manufacturer of the
control provides suitable DNC software. However, if this provision is
not possible, some software companies provide DNC applications that
fulfill the purpose.
That might illuminate BD's comment: "Slave computers are a dime a
dozen and proper DNC software can start and stop anywhere in a program."
Might as well use floppy disks then.
I disdain using external devices. Machine shops are extremely hostile
environments for electronic devices (floppy disks, usb flash drives,
wireless networking, etc) and the more that can be eliminated via hard
wiring via Ethernet and/or RS232 is directly proportional to reliability
over time. In my rather limited 30 years of experience anyway. ;)
The FANUC Dataserver option on a Fadal with an F18i is a PCMCIA card slotted
in the back of the machine.
You can remove it and run it from the slot in the pendant. You can use the
cards that are for sale in the big box stores but the good ones are
purchased from Sandisk and they aren't the same.
Siemens, OTOH uses and actual hard disk drive on their 840D and when they
fail ( and the things do fail) it takes out your machine.
The PLC and everything else is on the drive.
What a Siemens owner must then do is purchase new hardware from the
manufacturer - made as an image from the original data. That is something a
user generally can't do.
We have several VF3's the one I use is almost a year old it has the 7500 RPM
spindle. I have engraved steel, brass and aluminum. I mostly run 6,000 rpm
and the machine has a default of 15. inch feed in it's engraving program. I
have used 20" feed in steel with .005 depth of cut. looked fine to me. I
used a 1/16 diameter carbide ball end mill. The higher speeds are nice and
they use it a lot on the other machines that run production. I cut mostly
steel and make fixtures and tooling.
I think the higher speed with the higher rapids is a good idea. If the
rapids seem to fast for you, you can set the default to a lower speed. Our
foreman set max rapids at 50%.
We have the 24 tool changer and several times needed more tools than that. I
would suggest you get as many tools as you could. You don't have to use all
of them, but you can't use them if you don't have them.
We got the programmable nozzle for coolant which is a real nice feature.
Also the USB port is nice to save programs on in addition to uploading to a
server. Having a program on my USB drive saved me a couple of times, when
someone deleted an upload they didn't think we needed any longer.
Also all the tables were not flat when new on delivery. So we milled off
.003 and got the tables flat all the way across. This was to improve
accuracy for the 4th axis.
Just throwing in my two cents worth, all good answers and valid
points. I have a 2001 VF-0E with 1mb memory, side mount tool changer
and 10K spindle. I run mold bases with a laptop to DNC programs 4 to
6mb files to the controller.
Spindles above 15K require tool balancing, that at 10 and 12K is not
as critical. 12K is a good way to go, I do a fair amount of engraving
and the tool makes a big difference as well. Take a look at the Onsrun
from J&L, I am getting good results. Once you get into ceramic
bearings 15K+, any hard hit has the potential to junk the spindle. As
a beginner, it is not a matter of if!
The 24 tool side mount tool changer has been much more reliable than
the umbrella styles I have worked with. If you have hard water the
tool tray will eventually rot out with electrolysis. Get to know your
Water and Ice stores or consider an RO system. I have the eight tools
I use most loaded in my side mount and touched off ready to go, so
many of my programs can be run with the addition of drills or form
cutters and setting the work offset.
Through spindle works well with deep hole drilling, but is generally
not worth the added expense of tools, tool holders and maintenance.
Programmable coolant will work great for the majority of machining.
High speed machining should be considered for 3-axis mold geometry
small cuts at elevated feed rates. Instead of taking 40 blocks at a
time the controller takes 120, more look ahead means less stutter when
the code is flying across the screen.
The high intensity lights are great for set up and examination of the
The table slots are typical, I think the threaded holes are metric and
work great with subsystems like Chick. I have an aluminum plate with
tapped holes and dowels pin holes to locate plate work and can run
three Kurt 3600V vises. The VF-3 I have run can hold five vises tight
and the VF-4 SS ran with six no problem. Most rapids are fast enough
to cover the table faster than you want to think about, use the 25%
and 50% Rapid Override buttons until you get use to it.
Last I checked, most of these options are available as a C or D
package, and I would get a VF-4 over the VF-3 for ten extra inches on
the table and only a few dollars more :) You are marrying this
machine, and will have to live with it for a while. Get the things you
might need and pass on the rest that you just won't use.
All software has its pluses and minuses, I am using Camworks which
will engrave out of the True Type fonts or can do single point text
from the Solidworks sketch. I have used stand alone Cam packages and
am getting back into Mastercam for an upcoming job. So whatever the
sales people tell you it is not a Star Trek replicator. Invest in the
software and training. Our Phoenix area Haas dealer holds free mill
training classes, and the local community college technical classes
and resellers are a great resource.
Just my humble opinion. Good luck. JL
Thank you for taking the time to share your experience with these
machines. Lots of useful data to ponder.
Are you suggesting that if you had to choose between the Super-Speed
option and a larger machine you'd go for a larger machine?
Also, I am starting to think that the option for the X and Y slots on
the table might not be worth it. After all, it seems that most of the
time one would use a fixture or plate of some sort to hold the work
Should I be considering any other manufacturer other than Haas at this
point? I am somewhat convinced to go with them due to proximity (we
are in Southern California) and reputation. Westec is coming-
up...should I wait and look at some other options? We do need the
machine relatively soon...I just don't want to make a mistake. As you
said, you sort of marry these things.
You can sometimes get good deals on machines that were running in a
show like Westec. You're kind of limited by the options the particular
display machine has though.
Fadals are in roughly the same price range (and in Calif.). My
personal preference would be for a comparable Haas if I had to choose
between the two. Other's mileage may vary.
I started running Haas machines about twelve years ago. I have
programmed for Fadal, Hurco and I still deal with Anilam on a regular
basis. Just like the software all machines have their quirks. Usually,
it is the little things like the way they manage work and tool offsets
or throwing in a non-standard G-code if you are writing programs by
hand at the controller. Westec is a great venue to check out all the
machine tools and get a real feel for features and foot prints. If you
can wait, take a look at what is out there. The similarities are
greater than the differences. Our Phoenix HFO usually runs a Westec
special to boost sales, I am sure other manufacturer's do to. Don't
hesitate to hammer them for discounts or an upgrade package. . If you
haven't already, check with your reseller on delivery times. If it is
a popular machine it may be 6 - 8 weeks before it is sitting on your
floor. Figure a week to power up and get a tech to do the set up and
I was contracted by a company here in Phoenix to set up a fourth axis
machine about two years ago. The XY threaded / slotted table had the
advantage of about four extra inches in Z, so the rotary had a little
extra breathing room. A Chick subsystem was chosen and could mount
directly to the XY table. You are correct that most machines get a sub-
plate / universal tooling plate / sacrificial plate, I have what
started out as a three inch thick piece of 7075 bolted to my table.
After eight years it is getting to 2 3/4" with a few oops gouges. The
only time I take the plate off is when I need the extra clearance for
a tall part or about once a year to check for electrolysis and re-
grease the table. If you go with the VF-3 or larger you can count on
the plate staying on there for quite some time. Marine grease is a
must, and a big flycutter to keep it pretty.
For $5K more I would opt for the VF-4 over the VF-3 and with a package
deal get the extra goodies - probably another $5K. 12K spindle would
be nice, I have no problems living with my 10K. If I could budget I
would get a a larger machine with the SS option, same reason I opted
for the VF-0E at the time I bought mine. I wanted the 10K direct drive
spindle, and the 30 inch X table. At the time it was $5,000 more than
a VF-0 and to me a no-brainer. The VF-0E was really the same platform
as the VF-2, the VF-2 at the time had the geared head. The VF-0 faded
over time into the more common VF-2. For me the smaller footprint and
big on options was the better choice. If you go with the VF-2 you can
get three vises and most plate work on the table, the VF-4 will hold
six vises and you won't have to open the end windows and move the part
around if you do run a large piece. Occasionally that four extra
inches in Y on the VF-3 / 4 would come in handy.
Granted we are talking about almost $20K difference between the VF-2
and VF-4. If you don't have a headache yet, what do you have in the
way of tools, toolholders, and vises. The toolholders at say $100 a
pop and pull studs at $20 a pop will set you back a decent chunk of
change. What ever you have, you can always use one more. You should
budget around $5K if you do not already have the basics in house.
Tooling preferences would be a good future topic.
If you have any doubts the VF-2 10K spindle, side mount tool changer
and add on package will be a great entry level machine and leave room
in the budget to tool up and get going. If you are rolling the
software into this budget count on between $6000 and $10000, still
another topic. If you think you will grow out of the VF-2 in 6-12
months pull the trigger on a bigger machine. Production means more
vises on the table, and less open door time. One last if, if you are
looking one to two years out at adding another machine anyway by then
you will know if you need the bigger machine or can add on another /
Just a quick comment on the forty tool side mount. It is a larger
circle that doesn't turn any faster than the 25, so your Cam post
needs to index to the next tool way before it is needed. I have a
handful of programs that use all 25 slots, most run at 12-18. And, the
USB port is nice for the transfer, I have run programs from the USB
flash drive - if it gets removed or bumped it is not a good thing,
falls into the not a safe practice.
It really is a big purchase, a lot to consider, worth the time to get
opinions and see what is out there. Do the math and one will fall out
as the best choice. Sorry for rambling, this thread is getting kind
of long, trying not to repeat to much of what has already posted. If
this topic goes to far into left field drop me an email. Glad to help.
Ditto what he said, except,
I have a VF-5 and would not have done it any other way,
however, if you are going to do plate work on a 5, keep in mind that
the spindle, even though it has 25" in Z, stops about 4.5" from the
table, meaning you will either have to "elevate" your plate, or use a
lot of extended holders, ask questions of your HFO.
I love my VF-5, the HRT 210 stays on the machine almost all the time,
the chick foundation is worth its weight in repeating setups,
keeping setups "keyed" off of the 50mm hole locations makes changing
from part to part much easier, I also have the chick grid
saved in Mastercam, thus when new jobs come up, I can accuratly lay
the stock in position and get going right away, or place tooling /
on location, lots of open space on the table to work with, even with
the 4th axis on the machine.
BTW, I have the 7500 geared head option, I cut everything from delrin
to 6al-4v Ti. with 17-4 and lots of 4340 in the mix.
Of course I bleed HAAS red, so after 15 years of working with them, I
Thanks for a very detailed discussion. I am retired and not in
the market for a CNC machine, but I appreciate the very clear and
detail summary and the time it took to type it up.
Unka' George [George McDuffee]
He that will not apply new remedies,
must expect new evils:
for Time is the greatest innovator: and
if Time, of course, alter things to the worse,
and wisdom and counsel shall not alter them to the better,
what shall be the end?
Francis Bacon (1561-1626), English philosopher, essayist, statesman.
Essays, "Of Innovations" (1597-1625).
JL, again, thanks for another post with lots of good info.
I have the Fadal guys coming out tomorrow to have a conversation. On
first inspection it seems that they may have a very significant price
advantage. Of course, the devil is in the details...I'll have to wait
until tomorrow to learn about options and additional costs.
There are also other considerations. We know that we are very likely
to move sometime this year. Perhaps towards the end of the year.
Haas has told us that moving their machines is not a traumatic
experience at all. Fadal's machines seem to be substantially
heavier. Not sure how much of a difference that might make.
Does your plate cover the entire surface of the table?
Any pointers in terms of subplate design? What hole pattern have you
found is best? Do you have both threaded holes and plain holes for
pins? I would imagine the subplate bolts to the table via recessed
bolts and t-nuts, correct?
It's starting to feel that way.
That brings up a question about a hypothetical scenario. On these
machines, if you have to, say, machine something at the end of a 20
foot extruded piece...do you just open the side windows and that's it?
Yup, that's where you can drop a lot of change in a microsencond. We
put some tooling in the package but I am sure it won't be enough. Is
Yeah, we've discussed this idea. It might make more sense to buy
something just slightly larger than what we need for the work to be
done now (which a VF2 will cover nicely) and then make decision on a
larger machine a year or two down the line if things are going well.
Rambling? If this is rambling I want more of it!