Re: Pulse Gen

hi Wally,

Good points. No, actually I was only thinking of the PulseGen hardware
for my software efforts. No driver for EMC planned. A TSR for DOS would
be a possibility, as would be "sharing" the driver (function call or
subroutine) code for other users.

I hadn't stopped to consider the speed issues, as I am thinking from a
"small mill" mentality. Probably nothing bigger then a FB-2 or Grizzly,
or perhaps a "Dream Machine" of similar proportions, from what I gather.
200 IPM! In my current mindset, 20 IPM is fast! But yes, I
understand.
I recall seeing the 14 I.C. figure too, I need to see what Mariss has
for a schematic, or study the block diagram a little more.

The 5tpi is something to think about. I have 20 tpi on the little
Sherline, and a few pairs of what I think are 8tpi. x 3/8". I think
they may possibly be metric, as the shaft end was not a simple English
dimension, and some of the 3/16" (?!) hardware associated with them
turned out to be metric! Anyway, I am just realizing that the belt
reduction used with ball screws must also be to get more steps/inch, not
just for power as I originally surmised. Would have been nice to drive
them direct with a flex coupler. What steps/in should I be shooting
for? And what's realistic?

I'd appreciate your input.

Alan KM6VV


Wally K wrote:

>
> Alan, are you talking about writing a driver for EMC.
>
> As for pulsegen circuit. It seems overly complex for the performance
> and cost. If i remember right it takes 14 IC's per axis and has a
> max freq of 8khz.
>
> If my calcs are correct a 5tpi screw with a 2-1 belt reduction and
> 1/2 step mode will require 13.3Khz for 200IPM rapid.
>
> I do not think you should settle for less than this performance with
> the complexity and cost of the pulsegen circuit. (but this is a dam
> cleaver circuit).
>
> Let me know what your thoughts are.
>
> Wally K.

> <SNIP>