Understanding Machine Points
Machine points are used to reference the origin (X and Y axes) of machining instructions. These are not used to reference the location of the part itself – base points are used for part origin within the product.
When working with machine points, it is important to understand the different virtual machine fields. There is a normal machine field that uses machine points 1 through 8. Then, there is the mirrored machine field, which uses machine points 1M through 8M – the “M” designates the mirrored field. The image below better describes the machine fields.
The images that follow will show how each of the machine points affects how the part will be machined (normal and mirrored fields). Notice as you look through the images that changing the machine point also changes the location of the faces.
Looking at the cabinet parts again, the sides, top, and bottom would have the following machine points.
Machine points are often based on which face will receive the majority of machining. Also, most vertical parts will have machine points that reference the bottom, the front face of the interior of the cabinet. Most horizontal parts will have machine points that reference the left, front face of the interior of the cabinet.
The image below shows how the left and right sides are drawn with machining. The left side has a machine point of 1, and the right side has a machine point of 2M.
Machine points and faces, in text
The images above carry most of the detail. This section restates the same relationships in text for quick reference.
Machine points set the X and Y origin for machining instructions on a part. They do not set the part's position within the product — base points do that.
Normal field: machine points 1 through 8.
Mirrored field: machine points 1M through 8M. The “M” designates the mirrored field, which flips which faces receive machining.
Changing a part's machine point also changes where its faces are. Machine points are normally chosen so that the face receiving most of the machining is the one being referenced:
Most vertical parts (sides, partitions) reference the bottom, front face of the cabinet interior.
Most horizontal parts (tops, bottoms, shelves) reference the left, front face of the cabinet interior.
Worked example: in a standard cabinet, the left side has a machine point of 1 and the right side has a machine point of 2M.
Machine point alone does not decide Face 5 versus Face 6 for an individual operation. The machine token's own parameters do. If one machining operation is on the wrong face while the rest of the part is correct, check that operation's token parameters rather than changing the part's machine point — several tokens (including CAMLOCK, CONST, HOLES and hardware tokens) carry their own face controls. See Machine Tokens and Adding Machining to Parts.