[flexbex]

Hello I saw two different design aproaches for attaching the Gantry to the Table. One was to have the linearguide on top of the table or on the side. Could somebody explain me the benefit of both versions in general.
For my specific design I have the folowing considerations to make. My Gantry will be very long(3500mm) and thus heavy. So I was thinking that when I put the linear guide on top it will be more suported and the load is spread more equally on the sled. But on the other hand I tend to use a rackpionion for which it would make more sense to put it on the side as the teeth would face down. But these are just my unexperienced assumptions.

Thanks for replying

Felix

[flexbex]

These would be a drawing of both versions. Just to clarify what I mean

[RCaffin]

Having the rail UNDER the structure (top mount) does keep the muck out.
However, in the way you have drawn them, the side mount has the rails much farther apart, giving greater stability.

Cheers
Roger

[kawazuki]

Having the rail UNDER the structure (top mount) does keep the muck out.
However, in the way you have drawn them, the side mount has the rails much farther apart, giving greater stability.

Cheers
Roger

With a gantry 3,5m wide I don't believe a few additional cm's will have a measurable effect? With a top mount all of your static weight is directed straight down and into your base structure whilst the side mounts will be loading predominantly one side of the block and directing the forces through two 90 deg bends before reaching structure - not good in engineering terms. The top mounts may suffer to a degree on resisting side loading where the side mounts would excel - depends on the relative weights of the 'moving head' and gantry as a whole and rapid speeds as these are the biggies that have to be resisted in each axis?

[RCaffin]

I missed the rather fine lettering saying 3.5 m.
In that case I would go for top mount.

Cheers
Roger

[flexbex]

Ok thx.