I was searching Ebay today and ran across this listing, which seems to be a nice complement to Shapeokos and other machines using a series 20 8020 extrusion for their "Y" axis. http://www.ebay.com/itm/MakerFoot-R...283?pt=LH_DefaultDomain_0&hash=item1c43c1b3fb I've not used this, seen it in person, or even have any affiliation with the folks selling it. It looks like a good and needed product, based on my Shapeoko. Larry