60S 



BLOCK MACHINERY. 



Block Ma- take a future opportunity of presenting our readers 

 _ c u> *")' with these, or at least the most curious among them. 

 / ~""* See Sawing Machinery. 



To trace the whole process from the tree to the 

 finished block, we shall commence with No. 1. The 

 straight cross-cutting satv. This is a saw operating 

 cry nearly in the same manner as the carpenter's 

 hand-saw. The timber is brought to the mill in long 

 trees, (of elm for the shells of the blocks, ) with their 

 sides rudely squared by the chip axe, so as to become 

 irregular ottagons in their transverse section ; these 

 are drawn by the machine upon a long horizontal 

 bench, which is situated in the yard ; and one end of 

 the tree is brought through the window against 

 which the machine is placed, and, being adjusted to 

 their proper place, is cut across by the saw ; exactly 

 the proper length being cut off the end of the tree 

 to form the shell of that kind of block for which the 

 piece of timber seems best adapted, either as to its size 

 or quality. This machine is only used for the largest 

 trees. 



No. 2. The circular cross-cutting satv, is for ex- 

 actly the saroe purpose as the former machine, but is 

 applied only to the smaller trees : It is a very curious 

 piece of mechanism, difficult to be described in words. 

 The timber is brought as before, through the win- 

 dow. The saw is a circle, with its axis parallel to the 

 length of the tree. This axis is so mounted in a cu- 

 rious form, that it can be moved in all directions, ei- 

 ther raised up, or moved sidewise ; but in all these 

 motions its axis continues parallel to itself, and the 

 saw continues in the same plane. The saw continues 

 in rapid motion by the mill ; and the attendant apply- 

 ing the saw, by m*ans of turning a handle, to the 

 side of the tree, which it euts into about one-third 

 the diameter of the saw, and perhaps half through the 

 tree, then he does the same on the top of the tree, 

 next on the opposite side, and lastly beneath, if it is 

 necessary, till the wood is quite cut across from its 

 different sides. By this means a tree could be divi- 

 ded by a saw which could not be of sufficient diame- 

 ter to reach through from any one side. 



No. 3. The reciprocating ripping saw. The blocks 

 cut by the last machine are here cut in the direction 

 of the grain of the wood, first into two, three, or 

 more pieces, in one direction, and then in a direction 

 perpendicular to the former, so as to reduce the logs 

 into the size for the scantling of the required block. 

 This saw is on the same principle as that in common 

 use in America and other countries, and which has 

 * often been described ; but the construction of the 



machine is somewhat different. The largest blocks 

 only are sawn or ripped up by this saw ; the smaller 

 ones being cut in the next machines, which are 



No. 4. The circular ripping satv. They have four 

 of these, each consisting of a circular saw, projecting 

 partly up through a table similar to a carpenter's 

 bench. The picces-of wood being applied to the saw, 

 are cut through the length of the grain, and divided 

 into the proper scantling, in the same' manner as by 

 the foregoing machine ; but this is applied to the 

 mailer sizes. 



These are the machines appropriated for converting 

 the timber, and occupy one of the wings of the build- 



ings. The parallelopipedons which are formed here, Block Ma- 

 are carried to the opposite wing of the mill, where the 

 machines for forming them into blocks are situated. 

 They are as follow : 



No. 5. The boring machines. The blocks thus 

 sawn out, are fixed into a frame, and two centre bits 

 are applied ; one to bore a hole for the centre pin, 

 and the other, perpendicular to this, can be brought 

 to bore a hole for the commencement of the mortice 

 which is to contain the sheave ; the latter borer can 

 be so fixed as to bore either one, two, or three 

 holes, according as a single, double, or threefold 

 sheave block is wanted. Five of these machines are 

 used. 



No 6. The morticing machines are most ingenious 

 and perfect pieces of mechanism, which might be ap- 

 plied to many other useful purposes ; each gives mo- 

 tion to chisels, which mortice out the cavities for the 

 reception of the sheaves in two blocks at the same 

 time, if single or double blocks ; but in morticing 

 threefold blocks, only one is done at once. Three of 

 these machines are used. 



No. 7. The corner satv cuts off the angles of the 

 parallelopipedons which have passed through the 

 above machines. There are three of these machines. 



No. 8. The shaping engine is a curious engine, hi 

 which ten blocks, previously morticed, and with their 

 angles taken off, are fixed by their extreme ends, be- 

 tween the runs of two equal wheels fixed upon the 

 same axis. These having a rapid rotatory motion given 

 them, the blocks are successively brought against the 

 edge of a fixed gouge, which forms the outsides of 

 all the twelve blocks to the segment of a large circle, 

 which they describe by their rotation with the large 

 wheels. The gouge has also a progressive motion 

 following the curvature the block is intended to 

 have. When this is done, all the blocks, by an in- 

 stantaneous movement, are turned half round, so that 

 the sides which were towards the centre of the circlei 

 are now brought outside ; and the whole machine 

 being again turned about, these sides of the blocks 

 are formed by the same means as the former. The 

 shaping machine, therefore, forms the outside of the 

 blocks to their proper figure They have three of 

 these engines for different sized blocks, though ei- 

 ther of the machines will receive several sizes, among 

 which the differences are small and progressive. 



No. $). The scoring engine forms the scoring of 

 the blocks, which is a groove round its largest dia- 

 meter, for the reception of the strap of the block. 

 This groove is shallow, where it passes over the ends 

 of the pin of the block, and at one end ; but at the 

 other end, it is of considerable depth. Only two of 

 the scoring engines are required, as they will admit 

 a great latitude of different sizes, and tluy perform 

 so quickly, as to score all the blocks made by the 

 other machines. 



The foregoing machines are appropriated to the 

 formation of the shells of the blocks. Afterwards 

 they are trimmed, polished, and finished by hand, as 

 the surfaces are somewhat rough, though exactly the 

 true shape and size ; and this is almost as expensive 

 an operation as any of the preceding, not because the 

 blocks require much to be taken off to make them 



