1 or 2 lead screws

[spoolin_20b]

hello every one im building a 1200 * 1200mm gantry router and was wondering should i use 1 or 2 lead screws to move the gantry???

[Guldberg]

If you can, go with one. I have 2, its just twice the problems:-)

[Greolt]

It all depends on a lot of other things in your design.

How good are your X axis bearings? How rigid your frame and gantry?

1200 is pretty wide to have one screw under the center.

But again that depends on the rest of the structure.

Also different people have different expectations as far as accuracy is concerned. And how hard they are going to push their machine.

My router has very good bearings and rigid structure but I drove it from both sides and am glad I did.

But then what I expect and will accept will be different from the next person.

Now I know that all does not help much but if you give a better idea of your design it will make comenting much more usefull.

Greg

[ger21]

If you go with 1 screw, your gantry needs to be rock solid and have absolutely no chance of racking (no easy task, imo). 2 screws takes care of that problem, because each side is held in place by it's own screw.

[jcc3inc]

Hello Aussie,

Go with (2) rack and pinion drives and forget the leadscrews. You'll have many fewer problems and have a good drive. I made a machine as a test bed for a CNC programming effort and I'll email you pix of mine. Leave me a private message with your email so I know where to sent the pix.

There's another guy in Australia has made a machine. I can give you his info too.

Regards,
Jack C.

[TSJ]

Can you post the pictures of your machine. I am interested in the gear reduction for the rack and pinion portion.

[spoolin_20b]

i managed to get a price for some ACME threaded rod 7/8-6tpi 3.6m or 144' long for $100AUD what type of nuts should i use on the rod???