Re: Talking to RS232C, Pulley belts & Increm. / Absolute

Hi John,

#1 regarding the belt.

it sounds like your belt is a wide flat belt with lots of Vee's in
it. this is a type of power transmission belt. It is designed to
slip less than a one Vee grouve belt.


#2 serial comm. I can't help on that one, unless you see some
numbers like 7N300 or 8N9600 where the first number is the number of
bits, the letter is your parity, N or P N for non-parity or P for
parity.

#3) Absolute is how far from Zero you are. 1,2, 3 will move 1
form zero 2 will move 2 form zero and 3 will move 3 from zero. a
total of 3 from zero after you send those three commands.

Incremental is how far from 'where you are now'
1,2,3 will move 1 from where you start, 2 from that new point and 3
will move 3 from that new new point so you would be 6 from where you
started. no relation to zero as you could have started 20 inches
down the part in a facing or boring application.

On a lathe it is one of those "I need to take off another 10 thou, so
the dia is 3.756 now, and my distance from zero is ......

*or*

-0.005 and presto -10 thou ! (for you unfamiliar with a lathe,
one takes 0.005" off each side of a diameter of a spinning piece to
reduce the diameter 0.01")

Hope that helps.

--- In CAD_CAM_EDM_DRO@y..., "John" <johnhe-uk@s...> wrote:
> First of all I have to say thanks to everyone on here who's helped
these
> last few days answering my annoying questions. Since plugging the
lathe in
> my learning curve has become more than vertical. I can now program
the
> machine's own controller with simple stuff which is great fun
because it
> looks really hard to everyone else! `.^)
>
> However, I have a few more questions I'd like to ask and I thought
it'd be
> easier to ask them all in one post. So here goes:
>
> 1.) Pulley belts
> The belt that connects my spindle motor to the spindle itself is
making a
> squeeking, rubbing sound. I've slowed the machine down and it
appears to
> only squeek, or rub, as certain points of it go passed. I have run
the
> machine up and down to try and bed the belt in incase it was just a
bit
> stiff but that's not helped. The pulleys have radial grooves (Why
not axial
> like stepper pulleys?) and the belt does sit in them. I was worried
at first
> it may be the chopper wheel rubbing on the tach's sensors but it's
not.
>
> 2.) RS232C
> I got the null modem and plugged the machine in to have a mess
around but
> with no luck. I've written to the guys at Denford and asked them
the details
> of the controller such as it's handshake type and that. I have been
trying
> with WIN CNC 2K. Are there any other programs that would allow to me
> communicate with it thru the RS232C? I believe I have it plugged
into my
> serial comm 1 port for the mouse.
>
> 3.) Absolute and Incremental
> What do these two mean? It took me a while to work out that if I
said:
> X= 0
> Z= -100
> Then,
> X= 0
> Z= -200
> That I'd end up at Z= -300 but there is some funky stuff gong down
in
> absolute. For instance, if I ask the machine to move the two at the
same
> time it starts churning away, sometimes asking it to move the X
means the Z
> ends up moving. I switched it over to incremental and all these
problems
> went. What's the difference between these two?
>
> Thanks again, I'm off to play around with the screw threading and
circular
> interplotation buttons, I haven't tried them yet,
>
> A very happy lathin' John Heritage