This wonderful old plane is part of the Museums collection. It was mainly used for creating rebates in timber ntypically the rebate around doors. This type of plane was one of Stanley’s most popular tools favoured nby door fitters and hangers.
nAs a bevel-down plane pattern type, it is generally used by joiners and furniture makers for forming the noccasional rebate and especially for cleaning up machine marks from spindle moulders before the finish is applied.
The small three way adjuster with the screw in the middle seen here just in front of the blade could be loosened, the small three way adjuster turned exposing a small blade which would then be tightened, this would cut the timber fibres stopping the blade from tearing the timber if used to cut across the timber grain, there is one on both sides of the plane.
REF:https://paulsellers.com/2016/05/rebate-plane-no1-78-filletster-plane/