开云体育

What is the equivalent in Mach2 to what is commercially called 'look
ahead'? Contouring most definitely requires this...

Thank you,
Bill Clemens

First you will want to download the Sound logic XML file from my web page
www.camobelldesigns.com

I did that Bob.
Where I was having trouble was the power supply I purchased from www.seanet.com The manual states a DB25 Board and it was confusing me...I am using your board and not the DB25.
I would like to call on your help if I could.

Robin

Spare time is what you would have if you didn't get so many emails/requests,
oops there goes another 5 seconds :-)

Greg

On Wednesday 25 February 2004 23:23, Digital audio Pro wrote:

I'm not right with you. We can go to the limit of good steppers with mach2
at 45 Khz,

but you can't ...

the reasons for this are not obvious at first ... but let me see if I can try
to explain. I have not seen Art's source code so I can only guess at how his
driver works .. but I think I am probably close.

Art has a pulse generator in what is known as 'ring 0' of the windows kernel
.. this is the 'highest priority' layer of windows. Art schedules a task to
execute at 45khz .. (probably using a mutex or some similar idea to get
somehting close to 'real time' from Windows) .. anyway .. lets say the
highest frequncy of pulses is 45Khz .. the next evenly spaced frequncey down
is 22.5khz ... if you want to generate 32Khz pulses you have to do 2 pulses
at 45khz spacing, miss one, then two more .. miss one, then 3 more etc .. so
the pulse spacing is no longer even ... the choice is either BIG jumps in the
frequncies, or non-evenly spaced pulses. This is reallity.

What happens when you feed non-evenly spaced pulses into a stepper motor? ..
power loss. The motor wastes power trying to follow the small accelerations
and decellerations of the non even pulse chain ... at low frequencies its not
too bad, 1 pulse, miss 1000. 1 pulse, miss 1001, 1pulse etc, but at high
frequncies it becomes significant. For steppers this is a killer, because it
is at high frequncies that the motor lacks torque, and you cant afford to
waste any on rough pulse trains.

The G2002 solves this. DO NOT mistake the 1 mhz maximum pulse frequency for
ever wanting to actually get 1 mhz out iof it .. that is not the purpose at
all. the purpose of such high base frequencies to act as a base from which
the actual pulses are generated is that you get very, very smooth pulse
trians. this means that you get more power from your motors, can spin them
faster, this means you can use higher gearing, get more torque at low speeds
from the mill, mor torque at high speeds too ...

So .. before dismissing the 1 mhz maximum clock rate ( I think it is 1 mhz,
it may be 4 mhz) as irrelevant .. it is never intended to use this high
frequency .. it is simply to get a very smooth, regular pulse train at lower
frequncies, to get the maximum performance out of the humble stepper. When
driven right you'll be *amazed* what they can do ...

--
RapidCut CNC Technology

CNC Plasma Cutter

Spare time....nopw THATS a concept....
;)

Art
www.artofcnc.ca

Hey Art I just wanted to thank you again for such a good product and
support beyond the call. I took your advice and have been running
v1.9 but since reading your lockdown report on v.4 I think I may
upgrade now.

Since you are going to have so much spare time on your hands ;), just
wanted to know when you will be able to whip out an equally wonderful
cad/cam solid model package for full 5 axis to go with Mach2-????

Mike T.

Hey Lim,

Belts work fine, use a fine pitch V-tooth non stretch belt. V-tooth
belts do not slip around the pulley, straight tooth belts may have
play between the teeth of the belt and the teeth of the pulley.
Accomodate your design to have tensioner options because belts tend
to stretch over time. May be make the stepper mounting plates with
long holes to be able to move the motor. Talk to you later,

jan.


--- In mach1mach2cnc@..., lye chuan lim <lyechuan@y...>
wrote:

Hi,

Recently someone ask me to built them a CNC machine
with a travel length of 60" for X & Y axis, since
he does'nt want to used lead screw for the machine,
and ball screw is very expensive, I was wondering if
anyone have try using timing belt instead of chain
and sprocket, can this concept work for a machine
intended to used for engraving ?, Pls advice.

Thanks.

Lyechuan.

__________________________________
Do you Yahoo!?
Yahoo! Mail SpamGuard - Read only the mail you want.

Hi lye chuan. I have seen a couple of pictures on cnczone from a
company in Canada that is using timing belts. You might try there and
do a search. I have spoken with Mariss at Gecko about this and I will
probably try the belt drive on the machine I hope to build this
spring or summer. Mariss tells me to move the mass I want to move,
that I will have to use the belts or go to a .500 pitch ball screw or
a good rack and pinion. I am currently using the rack and pinion and
it has served me well but it is still quite a bit of money to get the
good stuff.

Mike


--- In mach1mach2cnc@..., lye chuan lim <lyechuan@y...>
wrote:

Hi,

Recently someone ask me to built them a CNC machine
with a travel length of 60" for X & Y axis, since
he does'nt want to used lead screw for the machine,
and ball screw is very expensive, I was wondering if
anyone have try using timing belt instead of chain
and sprocket, can this concept work for a machine
intended to used for engraving ?, Pls advice.

Thanks.

Lyechuan.

__________________________________
Do you Yahoo!?
Yahoo! Mail SpamGuard - Read only the mail you want.

Hi Lye:

I use a 48 inch belt drive. Works great..

Art
www.artofcnc.ca

Olivier:

Sorry, I neglected that red/green thing. I will look into it.

I will add a g92 active LED as well.
Thanks,

Art
www.artofcnc.ca

John,

I am so so sorry. It completely skipped my mind that you had had eye surgery
recently. These damn senior moments keep comming to the point they are
starting to run together. Please do not put any excess strain on those
eyes. I can wait as long as it takes for you to be better.
Regards, PJH

Hi,

Recently someone ask me to built them a CNC machine
with a travel length of 60" for X & Y axis, since
he does'nt want to used lead screw for the machine,
and ball screw is very expensive, I was wondering if
anyone have try using timing belt instead of chain
and sprocket, can this concept work for a machine
intended to used for engraving ?, Pls advice.

Thanks.

Lyechuan.

__________________________________
Do you Yahoo!?
Yahoo! Mail SpamGuard - Read only the mail you want.

Art, would it be possible in the next developpement version to have a
G92 active led ?

it's not easy to know if there is a G92 active actualy (we have to
look at the axis offset DRO, or switch between fixture / G92 DRO
mode).


Did you correct the Estop green/red led status not reporting to a
macro ?

Olivier

I'm not right with you. We can go to the limit of good steppers with mach2
at 45 Khz, and we can't drive efficiently a good servo system with a higher
definition / speed / acceleration ratio. I don't speak about AC or digital
servo systems, where 45 Khz is very low, specialy if you have high PPR
encoders. Industrial machines are often at 1 Mhz frequencies, or more for
high end ones.

Even with stepers systems it should give a better response, specialy for
full or half step systems, because the timing will be near perfection.

Actually the frequency is limted to 250 Khz if i remember well. It's a good
value for hobbists, more would be too difficult to manage with. (signal
integrity problems).


The gecko 2003 is an open standard, so cheaper non modular interfaces could
come in a near futur.

It's too an opening in the direction of the futur, because nothing garantee
the parallele port and the new motherboards will continue to work with
mach2. A simple design change inside the PC low level components or a new
processor design could cause problems to the actual mach2 kernel.

More it will give the possibility to integrate mach2 in an embedded system
quite easily.



Olivier.

Robin,

What do you need help with?

First you will want to download the Sound logic XML file from my web page
www.camobelldesigns.com . The XML file will set you pins on the parallel
port correctly. Copy the XML file into your Mach2 directory. When starting
Mach2 select Mach2 not Mach2 mill and select the Sound Logic XML file
procedure.

For wiring the Gecko drives you should look at the pinout information from
Gecko drive. For the G201 you will connect you power supply common ground
to pin 1 of the gecko drive and the + voltage to pin 2 (use a fuse in this
line). The step and direction wires will go to pins 8,9,10. 10 is the +5
volts from the breakout board, 9 is the step signal and 8 is the direction
signal.

I am working on a detailed set of instruction and a wiring diagram for the
breakout board to the Gecko 201/210 drives.

Bob Campbell

--- In mach1mach2cnc@..., "Ron Ginger" <ginger@m...>
wrote:

Art, I assume you intend to continue active support and development

of the

Mach2 parrallel port software even after the G2002 is ready?

Although the G2002 sounds like a neat device it seems to me to be an
overkill solution- what you have in Mach now runs quite well for any
reasonable size and speed mill. Why shuold Anyone spend $350 to get

pulse

rates many times faster than their motors can move?

In my view the G2002 became so feature bloated it looks like Bill

Gates had

a hand in it.

ron

Ron

Not all people are doing machines for home use. There are many motors
that will drive faster then 45KHz (If you are looking at 1000 count
encoders).

Just my thoughts
Brian

Ron:

Yup, the printer port will be fully supported. No worries there..

Actually, the G2002 isn't too bloated. Its fairly simple. It does seem
expensive in the hobby market at the moment, but as printer ports dissappear
it will continue to look more atractive all the time. Its simply the next
step when the makers of PC's take away our access to things like printer
ports..

Art
www.artofcnc.ca

Robin:

Yes, you can use the license on another computer as well. Try the
alternative driver, run the SpecialDriver.bat file on the troublesome
computer. It may help.
Thanks,
Art
www.artofcnc.ca

Art,

I loaded Mach2 on another computor on my network, can I use the Lis.dat file on it as well?
Everytime I try to run Mach2 it crashes and reboots.
I just did download it from your site...I think it is different than what I have on the other PC...said French version 4.0


Robin

Art, I assume you intend to continue active support and development of the
Mach2 parrallel port software even after the G2002 is ready?

Although the G2002 sounds like a neat device it seems to me to be an
overkill solution- what you have in Mach now runs quite well for any
reasonable size and speed mill. Why shuold Anyone spend $350 to get pulse
rates many times faster than their motors can move?

In my view the G2002 became so feature bloated it looks like Bill Gates had
a hand in it.

ron