[mindoverflow]

Hi,

What are the application differences between linear slides (bearing and shaft) and linear guides (profile guide way and appropriate bearing), looking at the prices we would say the second is better by far, but how?

Any precision difference, load, smoothness .....

[Ealin]

I recently saw a video on youtube regarding this. If I remember correctly it depends on load, and the precision of the mount surface.

My conclusion was that round supported rails are better for a DIY like myself. Square slides require better alignment and a very flat and even mount surface.

I'll try to dig a bit after the video.

[Ealin]

Ah here. I managed to find the link.

[ame=http://www.youtube.com/watch?v=rq4Pis6Zhf4&feature=related]Round vs. Square Rail - YouTube[/ame]

[mindoverflow]

Thanks mate, that was helpful.

I'm about to build a lathe, I've ordered round slide rails some time ago that I'm waiting for the delivery.

[pending]

Wow building a lathe your definitly going to want linear guides. I'm assuming your cutting metal with this lathe although even for wood I would advise? I've used both of these and found out the hard way lol...slides are good for linear motion and do well for doing just that linear motion...you can use them in a cnc as long as your cutting wood or something softer. Otherwise you automatically lose precision in these types of bearings because there made with play. So if you plan on cutting aluminum or anything else I would suggest linear guides. You simply can't cut on a lathe or a cnc with any precision past + or - 1mm with slides. That's what I've found...and I was also using supported rail slides...lol the unsupported are worse because they can bend which makes the precision a little worse.

[Pysiek]

So square rails are better? I will use 8020 frame on my machine is it straight enough to support the square rails? Is it harder to align two square rails to make sure they are parallel to each other?