Document ID: chunk:federal_register_of_legislation:F2024L01024:front:0:p102
Version: federal_register_of_legislation:F2024L01024
Segment Type: other
Provision Reference: 
Character Range: 288399–291257

one or more linear axis; and
b. Three or four axes which can be coordinated simultaneously for "contouring control"; or
2. Five or more axes which can be coordinated simultaneously for "contouring control" having any of the following;
a. "Unidirectional positioning repeatability" equal to or less (better) than 1.1 µm along one or more linear axis with a travel length less than 1 m;
b. "Unidirectional positioning repeatability" equal to or less (better) than 1.4 µm along one or more linear axis with a travel length equal to or greater than 1 m and less than 4 m; or
c. "Unidirectional positioning repeatability" equal to or less (better) than 6.0 µm along one or more linear axis with a travel length equal to or greater than 4 m.
Note: 2B001.c. does not apply to grinding machine as follows:
a. Cylindrical external, internal, and external‑internal grinding machines, having all of the following:
1. Limited to cylindrical grinding; and
2. Limited to a maximum workpiece capacity of 150 mm outside diameter or length.
b. Machines designed specifically as jig grinders that do not have a z‑axis or a w‑axis, with a "unidirectional positioning repeatability" less (better) than 1.1 µm.
c. Surface grinders.
2. B. 001. d. Electrical discharge machines (EDM) of the non‑wire type which have two or more rotary axes which can be coordinated simultaneously for "contouring control";
2. B. 001. e. Machine tools for removing metals, ceramics or "composites", having all of the following:
1. Removing material by means of any of the following:
a. Water or other liquid jets, including those employing abrasive additives;
b. Electron beam; or
c. "Laser" beam; and
2. Having two or more rotary axes and all of the following:
a. Can be coordinated simultaneously for "contouring control"; and
b. A positioning "accuracy" of less (better) than 0.003°;
2. B. 001. f. Deep‑hole‑drilling machines and turning machines modified for deep‑hole‑drilling, having a maximum depth‑of‑bore capability exceeding 5 m and specially designed components therefor.
2. B. 002. Numerically controlled optical finishing machine tools equipped for selective material removal to produce non‑spherical optical surfaces having all of the following characteristics:
a. Finishing the form to less (better) than 1.0 µm;
b. Finishing to a roughness less (better) than 100 nm rms;
c. Four or more axes which can be coordinated simultaneously for "contouring control"; and
d. Using any of the following processes:
1. Magnetorheological finishing ('MRF');
2. Electrorheological finishing ('ERF');
3. 'Energetic particle beam finishing';
4. 'Inflatable membrane tool finishing'; or
5. 'Fluid jet finishing'.
Technical Notes:
For the purposes of 2B002:
1. 'MRF' is a material removal process using an abrasive magnetic fluid whose viscosity is controlled by a magnetic field.
2. 'ERF' is a removal