Best rails position on frame in a dusty workspace

When we were looking at commercialising tables, I looked at belts with an Aussie company. They involved the German engineers and the word was not to use them. The Steel used to reinforce belts was not stainless so not rated for any water splash due to rust damaging the belts. I might add we were not looking at dainty belts, more like 20-30mm wide to handle the torque and acceleration we were shooting for.

Use Kevlar reinforced belts instead of steel ones.

Todd Zuercher wrote:

Use Kevlar reinforced belts instead of steel ones.

Exactly.
Steel reinforced ones tend to break down when used on tight bends.

Todd Zuercher wrote:

Use Kevlar reinforced belts instead of steel ones.

Too long ago but I think it might have been steel for the torque required or the supplier did not offer kevlar. Not a lot of choice in the colonies..

Ok, thanks. I have easily founds Kevlar ones in France. So I will go for this solution.

I am thinking since few days about how to protect Y axis rails. I do not want to let rails exposed to dust, so I have found two solutions. The first one is to use "below covers" like this :
 
Those cover would be placed like on this picture :
 

The second one is to use a special Z head design with spacer to be able to put fairings on top of rails. Those fairings would be made of bent aluminum sheet and positioned like the violet lines on this picture :
 
It is cheaper and simpler to install, but I am worried about geometry issues that this solution could cause. The moment created under the rails in particular.
What do you think about these two solutions ?

Currently, the Y rails are the HGR15 ones, the beam is a 80x120 profile like this one :
 

The whole gantry without Y motor and torch is about 25kg. So I am pretty close to the target weight.
 

pit34 wrote:

 

It is cheaper and simpler to install, but I am worried about geometry issues that this solution could cause. 
 

The moment on the rails depends only on where the force is applied relative to the rails, it does not depend on what the load path is between the two. 
The convoluted load path will affect rigidity, more of a concern for a mill than a plasma. 

Your design looks good, and could easily be augmented with brush strips if required.