Dimension specification for the three parts related to assembly accuracy previously identified in #047 is explained.

(1) Meaning of "matching the assembly datum of the parts"...

(2) Method of dimension specifying for each part. (see [Fig.1] and [Fig.2])

By designing with dimension specifying datum surfaces on all parts to be coincided, post assembly accuracy can be assured. This design scheme utilizes three parts each with datum surface A, A', and A" to assure the assembly accuracy of X axis and Y axis.

In order to benefit from this dimensioning specification methods to realize low cost (can be assembles without highly trained labor) machines, the designer is required of the following.

	1.	Able to understand the assembly process.
	2.	Knows how the parts are machined.
	3.	Able to properly: specify dimensions, specify tolerances, specify part fitting.