Hello.
The Epsilon came in 2xxx and a 3xxx series. The following spec is for an Epsilon 3303.
Positioning accuracy is 12um,12um,9um for X,Y,X. All straightnesses are 12um. Squareness is 2 arcseconds. The two terms of the ballbar equation are 12 and 6. The Epsilon is a solid machine. Rack and pinion drives, Heidenhein scales with 19p40 readers. Original electronics for the motorized version were P and PJM with the HELP language running on Dec 11/xx series of computers using rt11 O/S. Subsequent retrofits in the DEA world are Unidea/P with Tutor software. There are a few XTNC with Metromec software. There are two with PR controllers. There is one Diamond spec Epsilon on the west coast whose spec is half of the above stated. It depends on where they bought it. There are a couple of people at Brown & Sharpe that are pretty good on these machines. There is a guy at Axis Metrology who is very good on these machines. There are two guys at Coordinate Precision that have built and rebuilt quite a few Epsilons.