A centering guide cage apparatus for interior wall drilling includes a drill-bit holder, a flange bearing, a centering guide cage, a flexible casing, a hand-grip turnbuckle, and a flexible drill shaft. The centering guide cage, equipped with plurality of shape-memory supports, is terminally connected to an outer race of the flange bearing. The centering guide cage is terminally connected a distal end of the flexible casing from the opposite end. The hand-grip turnbuckle is terminally pressed against a proximal end of the flexible casing. A distal end of the flexible drill shaft is terminally connected to the drill-bit holder as the flexible drill shaft traverses through the flange bearing, the centering guide cage, the flexible casing, and the hand-grip turnbuckle. The flexible drill shaft is radially connected within an inner race of the flange bearing, wherein a proximal end of the flexible drill shaft is engaged with a drill driver.

An adjustable pipe center; the lathe-center may be useful for supporting the end of a rotating workpiece having a hollow along an axis upon which the workpiece is rotating. The adjustable pipe center includes a shaft, a center-head having keyways, a plurality of bearing-fins, and a plurality of power-screws. The center-head is fixed to the shaft and is able to fit within the hollow of the workpiece. The plurality of bearing-fins is able to fit and slide within the keyways, with each having a bearing-surface for contacting the workpiece. The bearing-surface is disposed at an angle to the shaft-axis between zero and ninety degrees. The bearing-fins may be translated, functioning as an inclined plane to displace a workpiece resting against it. When the bearing-fins are collectively translated as desired, it may laterally adjust the position of the workpiece-axis relative to the shaft-axis.

A centering guide cage apparatus for interior wall drilling includes a drill-bit holder, a flange bearing, a centering guide cage, a flexible casing, a hand-grip turnbuckle, and a flexible drill shaft. The centering guide cage, equipped with plurality of shape-memory supports, is terminally connected to an outer race of the flange bearing. The centering guide cage is terminally connected a distal end of the flexible casing from the opposite end. The hand-grip turnbuckle is terminally pressed against a proximal end of the flexible casing. A distal end of the flexible drill shaft is terminally connected to the drill-bit holder as the flexible drill shaft traverses through the flange bearing, the centering guide cage, the flexible casing, and the hand-grip turnbuckle. The flexible drill shaft is radially connected within an inner race of the flange bearing, wherein a proximal end of the flexible drill shaft is engaged with a drill driver.

An adjustable pipe center; the lathe-center may be useful for supporting the end of a rotating workpiece having a hollow along an axis upon which the workpiece is rotating. The adjustable pipe center includes a shaft, a center-head having keyways, a plurality of bearing-fins, and a plurality of power-screws. The center-head is fixed to the shaft and is able to fit within the hollow of the workpiece. The plurality of bearing-fins is able to fit and slide within the keyways, with each having a bearing-surface for contacting the workpiece. The bearing-surface is disposed at an angle to the shaft-axis between zero and ninety degrees. The bearing-fins may be translated, functioning as an inclined plane to displace a workpiece resting against it. When the bearing-fins are collectively translated as desired, it may laterally adjust the position of the workpiece-axis relative to the shaft-axis.