Offset a solid with different offset values on faces

One way is to offset each surface of the solid, then make the new solid from these faces.

Dear Sean,

you could use BRepOffset_MakeOffset class (which is internally used by BRepOffsetAPI_MakeOffsetShape)
with its method SetOffsetOnFace():
In PythonOCC this could be done like so:
mode = BRepOffset_Skin; Intersection = 0; SelfInter = 0
builder = BRepOffset_MakeOffset()
builder.Initialize(sourceshape,thickness,eps,mode,Intersection,SelfInter,joinmethod)
for aface in localthicknesses:
builder.SetOffsetOnFace(TopoDS().face(aface), localthicknesses[aface])
builder.MakeOffsetShape()
offsetshape = builder.Shape()

Hope this helps,
Mark