Question about dual-leadscrew designs

[watsonstudios]

I'm fairly new here and have only been researching CNC routers for about 2 weeks. My question is - Is it easy to have 2 motors on the X axis instead of one motor with a pulley system?(Solsylva design) I am designing a dual-leadscrew table but i want to use 2 motors - I assume you connect them together (in series or parallel)
to run off of X axis of the controller. Also, Is there any problem with the 2 motors getting out of sync with each other, or is this system practical.
Any advise would be appreciated.

Jon

[ger21]

Typically, you use a 4 axis drive and each motor uses it's own drive. Using Mach3 to control you're machine, the motors are slaved together in the software. One added benefit with that, is you can put a seperate home switch on each side of the gantry, and the gantry will square itself when homing. You'll find that if building a router from wood, it's very difficult to build a gantry stiff enough that the gantry won't rack a little. The 2 screws prevent racking, and as long as it's built close to square, you should only need to adjust one home switch to square it up. (or let it square itself up)

Provided you don't try to run faster than the machine is capable of, they should stay in sync together just fine.

[CNCkitsandBITS]

Another alternative if your not using Mach software is to use two drives wired to the same pins on your parallel port. As ger21 pointed out if you have your machine set up correctly so as not to loose steps there should be no problems.

John

[watsonstudios]

Thanks for the info. I would like to look into how to use both motors on the same controller because I'm sure I'll add a 4th axis at some point. I am planning on using mach3 for control.

Can I use Mach3 and still wire both motors to the X control?

[SCHootie]

I asked virtually the same question: question:http://www.cnczone.com/forums/showthread.php?t=33507
I now have received my order from sdpi now though. As I have asked before, would using two ~200 to 250oz motors replace using one ~425 motor and the belt? I am building out of steel instead of wood, so I'm hoping to take advantage of the hopefully extra rigidity. If this would help take care of squareness, all the better.

[CNCkitsandBITS]

Take a look here.

http://www.cnczone.com/forums/showthread.php?t=9305

And here

http://www.cnczone.com/forums/showthread.php?t=2477

John

[CNCkitsandBITS]

Watsonstudios please take a look here for my opinion on dual screws and belt and pulley. Please keep in mind it is just my opinion and may be wrong.

http://www.cnczone.com/forums/showthread.php?t=33507

John

[watsonstudios]

Yes, that helped. The last question is:

If I go with 1 controller card for each X motor, can I still use a 4 axis setup(meaning 5 controllers total) .Can I run 5 drivers total from Mach3?

[SCHootie]

If I went with an extra motor, I was planning on using another drive as well. I was actually hoping it would allow me to use smaller steppers which would also permit less powerful(read cheaper) drives.

[CNCkitsandBITS]

Originally Posted by watsonstudios Yes, that helped. The last question is: If I go with 1 controller card for each X motor, can I still use a 4 axis setup(meaning 5 controllers total) .Can I run 5 drivers total from Mach3?

Yes

John

[CNCkitsandBITS]

Originally Posted by SCHootie If I went with an extra motor, I was planning on using another drive as well. I was actually hoping it would allow me to use smaller steppers which would also permit less powerful(read cheaper) drives.

Let’s hope I am wrong with my take on two steppers against belt and pulley.

Would anyone like to correct me; I would like to know if I am wrong also?

John