The sensor housing is made from two UPVC pipe end caps and a short length of the matching UPVC pipe. The end caps must be at least 56 mm internal diameter and at least 25 mm internal depth.
Cut a length of the UPVC pipe which will give the 16 mm clearance for the sensor board mounting screws as shown in the drawing. Glue this into the bottom cap using solvent cement.
When the UPVC solvent cement has hardened, mate the top and bottom caps together. Clamp them together in a vice or clamp.
Drill an undersize hole for one of the screws which will secure the top cap to the bottom cap. Make this hole sufficiently undersized that the screw will form a good deep thread in the UPVC when first screwed in. Drill this size through both the top cap and the pipe.
Part the caps, and drill out the hole in the cap to the screw diameter. Remate the two cap halves with the holes aligned, clamp them together again, then fit a screw, making it form a thread in the hole in the pipe.
Repeat the process for two more screws at about 120 degree spacings. Offset one circumferentially a few millimeters so all three screws can be fitted only when the caps have one relative orientation.
Drill a hole in the centre of the top cap for the bearing housing. Make this hole a neat fit on the thread of the bearing housing.
Drill an undersize hole in the centre of the bottom cap for the thrust bearing bolt. Make this hole sufficiently undersized that the screw will form a thread in the UPVC when first screwed in.
Drill the two 3 mm holes for the sensor board screws halfway between two of the screws which secure the top cap to the bottom cap.
Drill and fit the mounting cap.
NEXT: Bearing assembly
