Ball Screw Vs Rack And Pinion

[EverydayDiesel]

Hello,

I am wondering what the difference is between a ball screw design and a rack and pinion design mostly on the X and Y axis.

What are the advantages of a ball screw vs rack and pinion.

Thanks in advance!

[adbuch]

Opinions will vary - here are several for your consideration.
David

https://www.shopsabre.com/education/bal ... ck-pinion/

shop sabre ball-screw vs. rack and pinion.jpg

https://www.cncrouterparts.com/which-is ... -p-99.html

Avid cnc - screw vs. rack and pinion drive.jpg

https://www.cnczone.com/forums/linear-a ... uring.html

cnc industry arena - ball screw vs. racks.jpg

[adbuch]

My "hobby" machines all use dual rack and pinion drive for the Y axis, single rack and pinion drive for the X axis, and "ball screw" drive for the Z axis.
These include Plasmacam 4x4 and two Avid CNC 4x4 and 4x2 cnc "routers". My professional machines use precision ball screw drives on all axes. These include Matsuura vertical machining center and Nakamura Tome cnc lathe. I have no complaints about the performance of any of these machines.
David

cnc machining centers.jpg

cnc mill.jpg

[Rodw]

I think for plasma, ball screws won't allow you to get to the velocities you require across the lengths you have to run. The ball screw will most likely whip. You might need a rotating nut design.

[EverydayDiesel]

Does anyone know a good brand of ball screw maker? I was looking at thomson which is certainly high priced but I dont know if they are any good https://www.thomsonlinear.com/en/produc ... ion_Rolled

[robertspark]

What are the advantages of a ball screw vs rack and pinion.

accuracy and mechanical advantage.

not suitable for plasma imo for X and y because of high acceleration and feedrate required, save your money and buy a rack and pinion instead.

accuracy not required .... you are using an air plasma cutter after all... it is not a milling machine or lathe / turning center where accuracy is required over a set distance (a ballscrew has uniform accuracy over a length of ballscrew)
https://www.google.com/url?sa=t&source= ... 6354103645

[adbuch]

Hello,

I am wondering what the difference is between a ball screw design and a rack and pinion design mostly on the X and Y axis.

What are the advantages of a ball screw vs rack and pinion.

Thanks in advance!

Diesel,
My first inclination when I read your original post was to say: "There are no advantages of the ball screw" for your application. I deferred and posted some "food for thought". Take a look at most of the cnc plasma tables out there - most are rack and pinion. As a mechanical engineer, my recommendation to you is to strongly consider the rack and pinion arrangement, and forget about ball screws (or acme screws).
David

Business Card 1.jpg

[EverydayDiesel]

My table will be 60% metal and 40% wood. The reason I was looking at ball screw is because 1 the shop Saber people use them on their cnc and most of the wood tables use a ball screw setup.

What is a good brand of rack and pinon to look at? I was lookimg at apex but they seem high for that amount of backlash

[robertspark]

mechmate use rack and pinion.

http://mechmate.com/

[SeanP]

I only used mod 1 rack, not expensive stuff, it's been fine, in use for the last 6yrs and most days as well, if you get the design right on the tension you wont get any backlash, my motor mounts were only cut from box section, nothing fancy but works great.