Abstract: Apparatus and method for constructing a manhole collar between an existing manhole cone and a precast manhole ring. The apparatus includes a circular slip form tube, tapered from a larger top diameter to a smaller bottom diameter; at least two support arms, radially extending from adjacent the top of the slip form tube for placement on a support surface, such as a road surface, to hold the tube at a selected height relative to ground level within a manhole cone; and a plurality of fasteners for attachment of a precast manhole ring about the exterior periphery of the slip form tube for supporting the ring at a selected height relative to the manhole cone and the roadway surface. The apparatus may include a concrete spill retention ring, placeable upon the top rim of the manhole cone and around the slip form tube to prevent concrete from entering the manhole cone.