In the end I found it quite easy to make except for the “V” blocks that run along the metal runner. The Stellafane plans use wooden blocks with “V” cuts that rest on the metal runner. I found these difficult to get exactly right and the body of the tester would rock whenever it moved. To remedy this issue I decided to use ring brackets that the metal runner passes through. This has solved the problem although the body of the tester is now permanently attacked to the base.
The tester is shown with a Ronchi grating in place, which is held in position by a flimsy hanger, that was no use for hanging things on but when turned the wrong way around made an excellent spring catch.
The easiest way to align the tester that I discovered was to use a torch shining through the viewing aperture. I made a wooden ledge that hangs from the top of the tester to hold the torch. The torch ledge is the triangular object visible in the wider view picture below, its resting on the bench in front of the tester.
