heh.
THK type linear rails can have their ends machined to overlap, providing long rails. This type of system will cost between $100 and $500/foot, i would estimate.
What sort of accuracy do you need?
750 to 1500lbs isnt that much weight really. But the forces involved if that is the weight of the lumber being moved may be much higher...
Your question is far to vauge. You need to specify budget, accuracy requirements, types of forces the unit will expect, environmental issues such as how much dust or liquids the device will come in contact with
cheers.
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