Bearing carriage running on an angle profile instead of using round tube

[Menno]

Has anyone yet tried to run the bearing-carriage on an angle profile instead of a round tube or bar?
An angle profile is easier to support, and therefore less able to bend.
But would there be significant more friction between the skate bearings and the angle profile than when running on a round tube?
Thanks.

[dertsap]

thats actually a brilliant idea

[Jason Marsha]

There is a machine that used angle, he mounted the bearings a little closer to the end of the bearing angle to offset the two corners touching. Hopefully he will see this post and show us the pics again.

Jason

[dertsap]

oops i really needed to read this again ,i misunderstood the post , i had a picture drawn up in my mind , i thought you were thinking of using angle iron and setting that at an angle to the gantry which would support the gantry and hold it down at the same time

[Menno]

A quick sketch made in paint (sorry, will never use MS Paint again : p )

The angle iron on which the bearing-carriage runs can be bolted or welded to the support beam (or a piece of wood). I think this way it'll be more easy to make a rigid machine.

Most angle profiles are hot rolled, and need to be sanded for a smooth surface. I've sanded a little piece of angle iron and i must say the surface is quite smooth, however I don't know how straight the profile is after sanding it.

[Jason Marsha]

A few pics to illustrate my point. The first pic shows the two corners touching. The second pic shows a small space between the corners.
The difference is that the shaft spaced with the nut (second pic) is closer to the corner of the aluminium angle and thus gives the clearance needed.

Jason

[dan dimock]

Jason;
What would happen if you place the bearings on the inside of the angle,
Dan

[tajord]

An idea jason, what if you round over or chamfer the edge of the aluminium like this........just a thought

[Jason Marsha]

Dan
Never tried it but a builder is attempting the design to run on the ends of angle iron so the setup will look like a square, in time we will see how it works out.


tajord,
That will work as well.


Jason