Re: looking for a XYZ cnc circuit throug lpt

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "turbulatordude"
<dave_mucha@y...> wrote:

>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "eli_cohen00"
> <eli.cohen@g...> wrote:
> >
> >
> > hi,
> > i'm loking for a XYZ cnc circuit throug lpt
> > i need a simple circuit that works
> > i'll use 3 steper motors - there is difference between steper
> motors?
> >
> > i found this circuit
> > http://hans-w.com/9908-09A.gif
> >
> > and this(not test yet)
> > http://hans-w.com/modular_cnc.htm
> >
>
> Hi Eli,
>
> Many people have made their own boards and their own driver
> circuits. You need to determine how much power you need, and how
> good of a circuit designer you are.
>
> In a simple form, a full step driver is pretty easy to build. Even
> just MOSFETS connected to the parallel port will run a motor.
> TurboCNC has this output ability, but it takes 4 pins per motor.
>
>
> You can make your own driver from designes on the web. The simplest
> are all full step and have somewhat limited amperage ( or current
> rating if you prefer that term)
>
> With your PCB machine, and 1/4-20 (or metric equalavent) leadscrew,
> you have 20 rotations per inch, times (I assume) 200 motor steps per
> inch, for 4,000 full steps per inch. this is great for full step
> driver. Considder that fine thread of 28 tpi with a 7.5 degree
> stepper (pulled stepper from printers) wouild still yield 1,344 steps
> per inch. Again more than accurate enough for a pcb machine.
>
> half and quarter step driver circuits are harder to build and harder
> to find. As you noticed, there are some driver circuits that use
> PIC microcontrollers.
>
> I would recomend you start simple, with a simple dual H-bridge for a
> bi-polar, or the simplier uni-polar driver. Much faster to get the
> motors to spin.
>
> Another benifit is that you may find it has more then enough speed
> and power for your machine, or that once you have your machine, it is
> easy to make more complex drivers with it.
>
> For a first time board, I would not use a PIC type as you will never
> know if your problems are software or hardware.
>
> check out the second sketch http://eio.com/jasstep.htm simple 4 pins
> from the PC to a uni-polar motor. it will take 12 port pins to run,
> but getting a second parallel port and this simple circuit is
> probably the fastest route to a working machine.
>
> But, I would say that building the machine before the drivers will be
> well worth your efforts. It has been pointed out that many people
> take months to make a circuit, spend hours and hours, then spin the
> motors and give up. Whereas those that build the machine, then want
> to see it move, make simple circuits and have machines that are
> running.
>
> Dave

first of all thank you for the explanation :)
i'll start building the machine, then i'll start to build the circuit
i'll come back when its ready ... some month :P