It sounds like you have your heart set on doing it this way so you have to at least try it and prove us wrong.........:rofl:

Tried and tested is the best route, I keep thinking of ways to beat the system but ultimately I always revert to linear rails, ball screws and servo motors

So what if I was to hire the gantry(Not a lot) and then protect the moving parts with a sheet of perspex ie enclose the belt and pullys.
I don't know of many people that want to "HIRE" a gantry but you defiantly wont protect them with perspex, only swarf ingress.:naughty: