Re: Completely new to all this...

Thanks for the help Ron,

That's cleared up some problems I had. I never even knew that a
breakout board existed. Just as a matter of interest, does the
power supply connect to the breakout board if you use one?

Do you know how many axes can be operated off Bob Campbell's Mach2
board and how many 'extras' can be operated as well (like coolant
etc.)?

Thanks
Warren Vickery


--- In CAD_CAM_EDM_DRO@yahoogroups.com, R Rogers <rogersmach@y...>
wrote:

> Warren,
>
> Nema 34's would be a good choice for that size mill. There are

many different configurations for CNC systems. Basically, there are
6 different components.

>
> A computer with 1ghz speed or faster (dell sells a 2.2 ghz for

$349).

>
> Controller software, there are many to choose from( I personally

recommend Mach2). Downloading demos from various sources for CNC
software is a good way to make a selection.

>
> A breakout board that is an interface betwen the PC and the motion

control system(If you use artofcnc Mach2, Bob campbells Mach2
breakout board is perfect), There are ways to get around using a
Breakout board but it involves soldering and making up DB25 plugs
and cables however, The breakout board adds many features to the
control like accessory control for spindle start, coolant, etc and
travel limits and home limits for the work envelope. Many safety
features like "watchdog" that monitors certain pins for
inappropriate signals from the PC to prevent unexpected movement,
opto-isolation (I think) to prevent high current from the drives
going back to the computer port. It does alot and is well worth the
investment.

>
> Servo or stepper drives, one for each axis and Geckodrives are an

excellent choice. There are others available and thats just the ones
that I use.

>
> Power supply and your choice of motors will dictate what its

output will need to be

>
> And lastly, Stepper or Servo motors. The debate is long on which

is better but here is my spin on it from what I've gathered from
these boards and my own personal experience. Steppers are rated in
holding torque and their torque dramatically decreases during
movement. Stepper drives are more expensive than servo drives. The
upside to steppers is that they are generally cheaper to buy and
they do not need an encoder to feed back to the stepper drive.

>
> Servos on the other hand will generally be rated at lower torque

for the same size as a stepper but, the torque is more even holding
and during motion (google "Servo versus Stepper" for a graph
displaying performance comparison). A belt reduction is suggested
used to get more RPM from the motor and higher torque to the
ballscrew. Servos must have an encoder to feed the motors position
back to the drive. Servos are generally more expensive and most of
the hobby drives will only work with DC brushtype servos. Servos run
cooler and the drives are generally less expensive. From reading
these boards for a long period of time servos seem to be more
reliable and less prone to problems. Whatever motors you intend to
use post the info from their dataplates on the list here and you
should receive an evaluation There are some really sharp people on
here (myself excluded :-) and they can help you out with it. Get a
mill and PC then find some appropriate motors and thats the best
place to start

> selecting the other various components.
>
> This is just a brief overview, largely my own opinion and does not

cover all aspects obviously.

>
> Hope this helps,
> Ron
> wvickery2003 <wvickery2003@y...> wrote:
>
>
>
> Hello everyone,
>
> I am completely new to all this CNC stuff.
>
> I would like to find out a bit about converting a chinese

mill/drill

> to CNC operation. I don't don't have anything at the moment.
>
> I am aware that I would need a PC, stepper controller board, power
> supply(???) and stepper motors. Would Nema size 34 stepper motors
> work (well) with a mill/drill machine? Would a Xylotex 4-axis
> controller be able to control size 34 motors (is the amperage etc
> correct)? What kind of power supply do you need?
>
> Are there any other reasonable (cheap...) controller boards around
> that would work and what could I do if I wanted to control the
> spindle and coolant from the computer?
>
> Sorry that I am asking so many questions which probably
> seem 'stupid', but I've got to start somewhere...
>
> Thanks in advance
> Warren
>
>
>
>
>
>
>
>
> Addresses:
> FAQ: http://www.ktmarketing.com/faq.html
> FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/
> Post Messages: CAD_CAM_EDM_DRO@yahoogroups.com
>
> Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
> Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
> List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@a...,

timg@k...

> Moderator: pentam@c... indigo_red@q... davemucha@j... [Moderators]
> URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
>
> OFF Topic POSTS: General Machining
> If you wish to post on unlimited OT subjects goto:

aol://5863:126/rec.crafts.metalworking or go thru Google.com to
reach it if you have trouble.

> http://www.metalworking.com/news_servers.html
>
> http://groups.yahoo.com/group/jobshophomeshop I consider this to

be a sister site to the CCED group, as many of the same members are
there, for OT subjects, that are not allowed on the CCED list.

>
> NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY POSTING

THEM. DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........

> bill
> List Mom
> List Owner
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
>
> ---------------------------------
> Do you Yahoo!?
> Check out the new Yahoo! Front Page. www.yahoo.com/a
>
> [Non-text portions of this message have been removed]