Like I said in my last post, I really think a belt drive for the X & Y- axis would work great (that thing would be fast!
), the sharpie would keep cost way down.
You should look into how the diy laser cnc machines are built,
like this laser here, see how the X & Y-axis use a belt to move each axis, also 80/20 material can be cut with a cheap cut-off saw to make any length machine you need (might be another option?).
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