Giant Spherical Components

This product line of very accurate, extremely high load carrying, spherical components is an important part of our kinematic component product line. These disks, or feet, are made of a hard (58 HRC) Martensitic stainless steel. This material has an extremely fine grain structure and a very high tensile strength of 285,000 P.S.I. These qualities along with the precision ground working surfaces give these components unparalleled accuracy and high load carrying capacity. The 40 inch (one meter) spherical diameter that is precision ground on the contact surfaces of these components is large enough to carry a huge 4000 pound (1814.4 kg) load, without permanent deformation. This 40 inch (one meter) spherical diameter is still small enough to provide for considerable misalignment in the form of tilt that typically occurs in large structures. See figure #1.

The smallest diameter version, of these components, is 7/8 of an inch ( 0.875”) [ 22.23 mm ] outside diameter and it is 5/8 inch ( 0.625”) [ 15.88 mm ] thick. The surface mounted version of this design is our part number SPH-875-SM which has a 1/4 inch diameter ( 0.25”) [ 6.35 mm ] with (20 threads per inch) blind hole on the back that is 3/8 inch ( 0.375” ) [ 9.5 mm ] deep. This threaded blind hole is used for mounting purposes. The back annular ring is lapped flat for ideal location. Additional holes, threads, or slots, can be Electrical Discharge Machined ( EDM ) to specific customer requirements.

The cylindrical post mounted version of the 7/8 inch 0.875” [ 22.23 mm ] diameter giant spherical component is our part number SPH-875-CPM. It has a precision ground cylindrical post on the back that is 1/2 inch ( 0.500” ) [ 12.7 mm ] plus nothing minus 0.0005 inch [ 0.0127 mm ] diameter. The length of the post is 1/4 inch ( 0.25” ) [ 6.35 mm ]. For mounting purposes, there is a #10-32 threaded hole that is ¼ inch ( 0.250” ) [ 6.35 mm ] deep in the center of the post.

The flange that is left between the 0.5000 inch diameter cylinder and the 0.875 inch outside diameter of the part is precision ground flat and square to the cylindrical post diameter within 0.0002 inch [ 0.00508 mm ]. The overall thickness of the head is 5/8 inch ( 0.625”) [ 15.98 mm ]. A larger diameter version of these components is 1 1/8 inch ( 1.125” ) [ 28.575 mm ] outside diameter. The surface mounted version of this larger part is our part number SPH-1125-SM which is 3/4 inch ( 0.75”) [ 19.05 mm ] thick. The threaded mounting hole in the back of the part is 1/4 inch diameter with 20 TPI (threads per inch). This threaded hole is one quarter inch 1/4" ( 0.25”) [ 6.4 mm ] deep. The back annular ring is lapped flat for ideal location. Additional holes, threads, or slots, can be Electrical Discharge Machined ( EDM ) to specific customer requirements.

The cylindrical post mounted version of the 1.125 inch [ 28.575 mm ] diameter giant spherical component is our part number SPH-1125-CPM. It has a precision ground cylindrical post, that is 1/2 inch ( 0.500” ) [ 12.7 mm ] diameter, plus nothing minus 0.0005 inch [ 0.0127 mm ]. The flange between the 0.500 inch diameter post and the 1.125 inch outside diameter is precision ground flat and square to the cylindrical post within (0.0002 inch), [0.005 mm]. The length of the post is 1/4 inch ( 0.250”) [ 6.35 mm ]. For mounting purposes, there is a #10-32 threaded hole in the center of the post that is 1/4 inch ( 0.250” ) [ 6.35 mm ] deep. The overall thickness of the body of this part is 3/4 inch ( 0.750”) [ 19.05 mm ]. The largest version of these giant spherical components is 2.00 inches [ 50.8 mm ] major diameter. The surface mounted version of this large part is our part number SPH-2000-SM.

It has a 1/2 inch ( 0.50” ) [ 12.7 mm ] diameter, with ( 20 threads per inch) threaded blind mounting hole, that is 3/8 inch ( 0.375” ) [ 9.5 mm ] deep for mounting the part. The back annular ring is lapped flat for ideal location. Additional holes, threads, or slots, can be electrical discharge machined to specific customer requirements. The overall thickness of the surface mounted version is 3/4 inch ( 0.750” ) [ 19.05 mm ].

The cylindrical post mounted version of the two inch, ( 2.00” ) , [ 50.8 mm ] diameter giant spherical component is our part number SPH-2000-CPM. It has a precision ground cylindrical post that is 0.750 inch, [ 19.05 mm ] diameter, plus nothing minus 0.0005 inch [ 0.0127 mm ]. The flat flange that is left between the (0.750 inch) diameter cylindrical post and the 2.00 inch major diameter of the part is ground flat and square to the post within 0.0002 inch [ 0.00508 mm ]. There is a 3/8-16 threaded hole, that is 0.320 inch [ 8.128 mm ] deep in the center of the cylindrical mounting post.

Surface Mount Spheres

Part Number	Major Diameter	Thickness of Head	Thread Diameter	Counter Bore Diameter	Counter Bore Depth
SPH-875-SM	0.875” 22.225 mm	0.625” 15.9 mm	1/4” 20 TPI	0.000	0.000
SPH-1125-SM	1.125” 28.575 mm	0.750” 19.05 mm	1/4” 20 TPI	0.625” 15.875 mm	0.032” .8128 mm
SPH-2000-SM	2.00” 50.8 mm	0.750” 19.05 mm	1/2" X 20 TPI	1.000” 25.4 mm	0.032” .8128 mm

Cylindrical Post Mount Spheres

Part Number	Major Diameter	Thickness of Head	Thread Diameter	Diameter of Post	Length of Post
SPH-875-CPM	0.875” 22.225 mm	0.625” 15.98 mm	#10-32	0.50” 12.7 mm	0.25” 6.35 mm
SPH-1125-CPM	1.125” 28.575 mm	0.750” 19.05 mm	#10-32	0.50” 12.7 mm	0.25” 6.35 mm
SPH-2000-CPM	2.00” 50.8 mm	0.750” 19.05 mm	3/8-16	0.75” 19.05 mm	0.50” 12.7 mm