Neutron Guide Alignment

The alignment of the neutron guides is based on our coordinate measuring machine (CMM). Each guide unit is measured on the Renishaw CMM in house and aligned with the laser tracker Leica 406, a total stations Leica T5000 and two theodolites on site.	We measure the front and back face of the guide units with respect to an additional measuring feature.	We add one of the three following features to the guides: 1.) Extensions 2.) A conical bore 3.) Fiducials
The conical bore: For the measuring on the CMM we put a steel sphere in the bore and measure the position and the cross sections.	The conical bore: For the alignment on site we put a fiducal in the bore.	The Extensions: The alignment plates are made of glass. They have a bore, a groove and a plane.
The Extensions, the best solution. It consists of two parts: alignment plate and extension. The plates are glued onto the units and the extension stands on top of the plates.	The extensions have three ceramic spheres, which fits perfectly to the alignment plates. The repeatable accuracy is 5 microns.	On site, the extensions allow for very quick and precise alignment.