. A dictionary of arts, manufactures and mines : containing a clear exposition of their principles and practice. ng in thecircles, or chuck, with an immensevelocity, should be loosened by the ac-tion of the tool, and fly out by theircentrifugal force. Without this provi-sion, the consequences of such an acci-dent would be dreadful, as the blockswould be projected in all directions, withan inconceivable force. 8. The scoring engine receives twoblocks, as they come from the shapingengine, and forms the groove roundtheir longest diameters for the receptionof their ropes or straps, as representedi
. A dictionary of arts, manufactures and mines : containing a clear exposition of their principles and practice. ng in thecircles, or chuck, with an immensevelocity, should be loosened by the ac-tion of the tool, and fly out by theircentrifugal force. Without this provi-sion, the consequences of such an acci-dent would be dreadful, as the blockswould be projected in all directions, withan inconceivable force. 8. The scoring engine receives twoblocks, as they come from the shapingengine, and forms the groove roundtheir longest diameters for the receptionof their ropes or straps, as representedin the two snatch blocks and doubleblock, under yig«. 131, 132. A, B, fig. 133, represent the abovetwo blocks, each held between two smallpillars a (the other pillar is hid behindthe block), fixed in a strong plate d, andpressed against the pillars by a screw 6,which acts on a clamp d. Over theblocks a pair of circular planes or cut-ters, E E, are situated, both being fixed on the same spindle, which is turned by a pulleyin the middle of it. The spindle is fitted in a frame f f, moving in centres at e e, so. 154 BLOCK MANUFACTUKE. as to rise and fall when moved by a handle/. This brings Ihe cutters down upon thablocks; and the depth to which they can cut is regulated by a curved shape g, fixed byscrews upon the plate d, between the blocks. Upon this rests a curved piece of metaih, fixed to the frame f, and enclosing, but not touching, the pulley. To admit the cut-ters to traverse the whole length of the blocks, the plate d (or rather a frame beneathit) is sustained betweea the points of two centres. Screws are seen at /, on these cen-tres. The frame inclines when the liandle l is depressed. At m is a lever, with a weightat the end of it, counterbalancing the weight of the blocks, and plate d, all which areabove the centre on which they move. The frame f is also provided with a counterpoise(o balance the cutters, &c. The cutters e e are circular wheels of brass, with rounded^es.
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Keywords: ., bookcentury1800, bookdecade1840, booksubje, booksubjecttechnology
