A three part rotating, sliding bearing guide for any size filament roll. I designed this for our Makerbot Repicator 2, but I'm sure it could be used on other machines. The filament guide pivots on a bearing, the bearing mount slides on the bracket, and the bracket rotates to align with either the left or right filament roll. For the bearing I used a McMaster Carr P/N 60355K503 bearing. The bearing presses in and requires leverage (ie: an arbor press, don't use a hammer). I mounted the assembly level with and 1.25" next to the factory sheet metal guide tube mounts (thru the plastic and into the sheet metal) using a #10 sheet metal screw, and predrilled with a 0.155" dia drill bit. The mounting location both penetrates the sheet metal for a good fastener anchor, and is close to but clears the factory guide tube mounts when the assembly rotates. Materials LIst: 1x No. R4 Bearing (McMaster Carr P/N 60355K503) 1x #10 x 3/8"L Screw (McMaster Carr P/N 90190A240 for 100) 1x #10 Washer, thin (McMaster Carr P/N 90126A514 for 100) 1x #10 x 1"L Screw (McMaster Carr P/N 90190A247 for 100) I printed PLA on high resolution with rafts, supports, and bridges, with %50 infill. When mounting the ball bearing (press fit), I shimmed the gap under the Bearing Mount with a plastic spatula to keep the Bearing Mount lip from snapping off as the bearing was pressed in. The Bearing Post tabs are a bit fragile, so don't "test" them with your fingers, and carefully push the Bearing Post into the pre-seated ball bearing. The Bearing Mount fits into the groove on the Bracket, and is captured by a 3/8" long #10 screw (and #10 washer) that threads into the printed screw hole on the back of the Bearing Mount. As described, I mounted the assembly centered and offset from the stock sheet metal guide tube mounts, on the "right" (facing the back of the printer) and close but with enough room to rotate the unit without hitting the sheet metal guide tube holders. I predrilled 0.155" for the mounting screw, and tightened to "snug" but left it loose enough for the assembly to rotate.