One grind rails question. (another alternative rail proposal)
 

Hi.

I've been thinking that the bearings can be installed at 45 degrees to avoid, grind the rails

One image.

Once you start grinding doesnt your reference surface disappear? You could drag the grinder, but then you would only have one pass to get it right.?

Ros,

No one has complained that much about grinding especially after the skate was developed.

If you slanted the wheels like this, you'll have all kinds of worse problems trying to get them in the same plane and an equal distance apart. If one wheel needs to be lowered, when you move it down, now it will be closer to it's mate on the other side of the gantry! In my opinion, you'd never get it sorted out.

Ok.. Don't understand very well your english sorry.
but this is other offer, possible.

Two bearings in side to side.

Is possible the wear bearing lateral, this bearing not is designed for work in 45 degrees.
And the rail is more dusty and need clean.

My opinion doesn't count, but I have experimented with angular thrust alignment of V-groove wheels on caster on VERY LARGE equipment and mining carts. Moving the wheels out of a natural vertical plane causes all sorts of headaches. Mechanically sound idea, but why the change? What benefits do you see?
If your trying to eliminate grinding, there is multiple options of over-the-counter steel/alum stock choices that would allow for a non-ground rail. If I recall, Art @ turning around had good success with a small 1/2 x 1/2 angle iron put V up so the wheels mated without grinding. A small deviation from the plans, but successful. The grinding of a MM rail is very easy and a repeatable operation that any person can do with a little guidance.
(Having done this twice now, it's a piece of cake!)

In my large scale mining cart operation style carts, We use 6" diameter cast iron V groove casters that ride on homemade "traintracks" made of 2" angle iron. It works well, and it's really cheap to fabricate.

I know I reached a tangent here, but I ask again....why?

...moderators (delete as necessary)

There have been many proposals for alternative rails. I wish people would draw the whole picture - include the rack, pinion, motor, motor mounting and the end of the gantry when you make your proposals please.

And another thing to add to the proposal drawing, is a standard layer of 5mm thick sawdust and chips lying on any horizontal surface. I suppose this is the main reason why this proposal doesn't get me interested.

Ros, many would not like the complexity that would get involved in mounting the V wheels at the angled position as shown in the picture and as G' has already mentioned - there are a host of other things we need to think about.

Sorry for my first comment, I was thinking the bearings were for the grinding skate, not the gantry. :)