This is an old revision of the document! BOM 2x http://openbuildspartstore.com/688z-ball-bearing-8x16x5/ 4x http://openbuildspartstore.com/openbuilds-solid-v-wheel-kit/ Or (up to 3657mm 12 feet) $61.14 http://www.mcmaster.com/#perforated-structural-framing-tubing Or ($216 per 1740mm - 5.7 feet) http://us.misumi-ec.com/vona2/detail/110300071070/?Brand=MSM1 http://us.misumi-ec.com/vona2/detail/110300070730/?Inch=0
