A magnetic-disk glass substrate of the present invention includes a pair of main surfaces, a side wall surface, and a chamfered surface between the main surfaces and the side wall surface. Regarding surface properties of at least one of the side wall surface and the chamfered surface of the glass substrate, an arithmetic average roughness (Ra) is 0.015 m or less, and a bearing factor of a roughness cross-sectional area when a roughness percentage is 60% is 95% or more in a bearing curve of a roughness cross-sectional area.

A magnetic-disk glass substrate of the present invention includes a pair of main surfaces, a side wall surface, and a chamfered surface between the main surfaces and the side wall surface. Regarding surface properties of at least one of the side wall surface and the chamfered surface of the glass substrate, an arithmetic average roughness (Ra) is 0.015 m or less, and a bearing factor of a roughness cross-sectional area when a roughness percentage is 60% is 95% or more in a bearing curve of a roughness cross-sectional area.

A grinding and/or polishing machine (10) for slabs of stone material, such as natural or agglomerated stone, ceramic or glass, comprises a support bench (12) for the slabs to be machined and at least one machining station (14) with a pair of bridge-like support structures (16, 18) arranged opposite each other with, above, a beam supporting a plurality of machining spindles (26). First relative movement means (19) move the slab in a longitudinal direction with respect to the machining station (14), while the beam moves transversely with respect to its length by means of second movement means (21). Each spindle is supported on the beam so that it can be swivelled by associated movement means (34, 35, 40, 50, 60) about an oscillation axis (33) which is parallel to, but separate from the motorized vertical axis (32) of the spindle. The spindles thus oscillate about the respective oscillation axes (33) in cooperation with the longitudinal and transverse movements, respectively, of the first and second movement means (19 and 21) so as to polish and/or grind the surface of a slab on the support bench.

A method for producing a heat-resistant roll, and a roll produced by the method, the method including: fabricating a roll part comprising 5 wt % or more of a clay mineral; grinding the roll surface of the roll part; conducting a surface treatment in which the ground roll surface is smoothed in a moisturized state; and forming a coating film of a clay mineral on the surface-treated roll surface.

A method for finishing an edge of a glass sheet comprises grinding the edge of the glass sheet with a grinding wheel. The glass sheet includes a first major surface, a second major surface substantially parallel to the first major surface, and the edge connecting the first and second major surfaces. The grinding produces a central edge portion and two chamfered edge portions connecting the central edge portion with the first and second major surfaces, respectively. The method further comprises polishing the central edge portion with at least one cup wheel rotated about a first axis substantially parallel with the first and second major surfaces of the glass sheet to polish the central edge portion, wherein an abrasive layer of the cup wheel comprises at least one of ferric oxide (Fe.sub.2O.sub.3), silicon carbide (SiC), and ceric oxide (CeO.sub.2).

A method for finishing an edge of a glass sheet comprises grinding the edge of the glass sheet with a grinding wheel. The glass sheet includes a first major surface, a second major surface substantially parallel to the first major surface, and the edge connecting the first and second major surfaces. The grinding produces a central edge portion and two chamfered edge portions connecting the central edge portion with the first and second major surfaces, respectively. The method further comprises polishing the central edge portion with at least one cup wheel rotated about a first axis substantially parallel with the first and second major surfaces of the glass sheet to polish the central edge portion, wherein an abrasive layer of the cup wheel comprises at least one of ferric oxide (Fe.sub.2O.sub.3), silicon carbide (SiC), and ceric oxide (CeO.sub.2).

An electronic device may have a glass housing structures. The glass housing structures may be used to cover a display and other internal electronic device components. The glass housing structure may have multiple glass pieces that are joined using a glass fusing process. A peripheral glass member may be fused along the edge of a planar glass member to enhance the thickness of the edge. A rounded edge feature may be formed by machining the thickened edge. Raised fused glass features may surround openings in the planar glass member. Multiple planar glass members may be fused together to form a five-sided box in which electronic components may be mounted. Raised support structure ribs may be formed by fusing glass structures to a planar glass member. Opaque masking material and colored glass may be used to create portions of the glass housing structures that hide internal device components from view.

The invention pertains in general to a latching mechanism for maintaining desired friction levels on an optical disc in an optical disc restoration device. In particular the invention pertains to devices, systems and methods for easily maintaining friction levels between pads and an optical disc in an optical disc restoration device for ease of adjusting friction settings during quality control, repair operation or when optimization settings are being set in an optical disc restoration device by a user.

The tool includes a base including a rigid carrier and a flexible collar encircling the rigid carrier; an elastically compressible interface; and a flexible buffer including a central portion that is located in line with the rigid carrier and a peripheral portion that is located transversely therebeyond. This peripheral portion is connected to the carrier exclusively via the interface and via the collar, wherein the collar is configured so that the tool is elastically deformable between a rest position that it adopts in the absence of stress and a reference position in which the transverse end second surface of the flexible buffer is pressed against a reference surface that is spherical and of radius included between 40 mm and 1500 mm.

The tool includes a base including a rigid carrier and a flexible collar encircling the rigid carrier; an elastically compressible interface; and a flexible buffer including a central portion that is located in line with the rigid carrier and a peripheral portion that is located transversely therebeyond. This peripheral portion is connected to the carrier exclusively via the interface and via the collar, wherein the collar is configured so that the tool is elastically deformable between a rest position that it adopts in the absence of stress and a reference position in which the transverse end second surface of the flexible buffer is pressed against a reference surface that is spherical and of radius included between 40 mm and 1500 mm.