To use it, place one fold of sand-paper only around the rubber; and applying it to the work, move it over the surface of the work, and across the grain of the timber, if it is possible. If the size of the work is smaller than the rubber, we must take short strokes, so as to be able to move the latter steadily, and not round off the work at and toward the edges. A very good plan, where extra care is required, is to either glue the sand-paper to the rubber, or else fasten it with a few tacks. Sand-paper glued to a flat board is very useful for small surfaces; but in this case, we rub the work upon the paper, and not the paper upon the work. The grades of sand-paper used upon pattern work range from No. up to No. 2, Nos. 1 and 1 being most commonly employed.

The surfaces of the hub or body of our gland pattern being straight in their outlines, we sand-paper them in the lathe, with the paper wrapped once around a flat rubber, applying the paper lightly to the work, and moving it very slowly over the work, in the manner in which a file is used. We next fasten the flange to the body by gluing it, by using finishing nails, or by both. If finishing nails are used, care must be taken to use a bradawl before inserting the nails, for fear of splitting the wood.

To make the pattern in the manner shown in Fig. 90, the method of procedure is the same as the above, with the exception that the tapering of the core prints must be vice versa, as in this case the core print the farthest from the flange will be the top one in the mold, and must therefore be given the most taper. And since the body of the pattern will lift with the cope, while the flange will remain in the nowel of the flask when the mold is taken apart (as shown in Fig. 91), the flange of the pattern must be made an easy fit to its place on the body or hub, and must not be left of a tight fit, as in the former case. A pattern of the form shown in Fig. 92 may be turned, flange and all, out

of a solid piece of wood; or, if too large for this, we may plane up a piece for the flange, and glue a hub to it; and when the glue is dry, turn up the whole pattern at one chucking in the lathe.

The construction shown in Figs. 92, 93, and 94 is so nearly the same, and the slight difference is so obvious, that an explanation of Fig. 94 will cover the ground. For Fig. 94 we plane up a piece over twice as long and more than half the size of the required flange, and out of this piece cut the two half flanges. If, however, the flange is of sufficient size to make it necessary to study economy, the two half flanges may be set out on the plank, lapping each other, as shown in Fig. 99. We next, with a flat scriber, draw a line on the chuck exactly through its cen

Fig.99.

ter, and set the half flanges to this line, and then screw them to the chuck, and turn them as if they were solid. By setting the halves exactly true to the line, it is insured that the flange shall part exactly at the center.

To make the pattern shown in Fig. 93, we take two pieces of wood long enough to make the two halves, and allow about half an inch or an inch to turn off each end, so that the impressions of the fork and center may not appear on and disfigure the finished work, and for other reasons hereafter to be mentioned. We plane these pieces on one edge and on one face, making them of equal thickness. We make the flat surfaces which come together, true, trying them with the winding strips shown in Fig. 37, to detect any twist. Our next operation is to insert the pegs,

and we may, for this purpose, adopt either of the two following methods, the more ready of which we will take first: Clamping the two jointed faces together, as shown in Fig. 100, we bore two holes right through the top piece and into

Fig.100.

the bottom, one to a little greater depth than the hight to which the pin is intended to project, as shown by the dotted lines. We then plane up a piece of hard wood, about two and a half feet long, to fit the holes tightly. It is just as easy to plane a long piece as a short one, and what is

Fig.101.

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scclion A.B. c

B B

left over will serve for a future occasion. A useful tool for preparing pin stuff is illustrated in Fig. 101, which repre

sents a hardened plate of steel, pierced with holes of the sizes of the pins usually required. The wood for the pins having been planed up to the required size, is driven with a mallet through the plate, saving a great deal of time, and making the pins more nearly round than is possible by hand work. In some of these plates the boles are made taper, as shown at A, in Fig. 101; this, however, is detrimental, and the parallel hole is the best, because it guides and supports the stick, while it does not impede the cutting action of the tool. A hollow formed around the edge of the hole, as shown in the sectional view, at B B, would improve that action; or it might be still further improved by inserting bushes in the plate, with a portion left projecting above the plate and beveled off to resemble a chisel, as shown at C.

Fig.102.

The pin stuff being prepared and inserted into one half of the pattern, the projecting end is then tapered off, as shown in Fig. 102. The formation of this projecting pin may seem a very simple matter; but if sufficient consideration is not given to it, a great deal of annoyance is caused to the molder, and the castings will

be imperfect. If we reflect for what purpose these pins are inserted, we shall find the proper shape. First, with regard to the projecting length, some workmen seem to be guided by the diameter of the pin, making it project to a distance equal to its diameter; but it is obvious that a short peg or pin will govern the position as well as a long one, and will be less liable to stick in the loose half of the pattern: hence it is better to let the protruding endstand out from three sixteenths to one half inch, and let

from one sixteenth to one eighth inch of the large part fit the hole, the nut being tapered off so as to be sure that the pin can be released easily. These conditions inevitably bring us to the parabolic form shown in Fig. 102. Another point to be observed is to make the pin of as large a diameter as is consistent with the work; for the larger the pin, the longer it will remain free from shake. Above all, it is essential that the pin be perfectly round at the part that fits the hole; and if these elements are neglected, castings will be produced of which the halves will not match, which is always very unsightly. Nothing is gained by making the pins to a tight fit in the loose half of the pattern, as they will not work that way; and the molder will enlarge the holes with a red hot rod, and then, after a little while, the charred part around the hole falls out, and the pin becomes too slack.

After inserting our pins, the two halves of our patterns are to be fastened firmly together; and this may be readily done by brushing the end faces with hot glue for a breadth of one half or one inch, according to the amount we have allowed our pieces to be larger than the finished work. Then we hold them firmly together with a screw clamp, leaving them until they are perfectly dry. If there is not time for the gluing, the two halves may be screwed together; and indeed, if the job be a heavy one, it will not be safe to trust entirely to glue, but to use screws or dogs. Dogs are a kind of square staple, made of steel, and of the form shown in Fig. 103; and two of them driven in each end of a pattern will hold its loose halves very firmly together. While

Fig.103.

very handy, however, on large or small work, they are