In Fig. 58 of "Pattern Making" a wheel pattern was shown that could not be drawn from the sand. In Fig. 44 the round pattern is made in two parts. Where the pattern is small this is frequently undesirable. Where there are only a few pieces to be made, the method described on page 82 of "Pattern Making" may be followed. When many eastings are to 1m* poured from one pattern a follow board should be used. If the pattern is ornamented or is of complicated shape, the making of a wooden follow board is very expensive. The moulder can make a follow board very cheaply as follows: Have a frame made to fit over the frame of a cope as in Fig. 52. The frame so made to be one-half the thickness of the pattern, as in 11. This is set in position beneath the cope and set on the moulding board. The cope is then rammed with sund as directed for the ordinary drag. The sand used is, however, to be especially prepared. Take ordinary new moulding sand and dry it perfectly. Then mix it with boiled linseed oil until it is nearly the same consistency or a little more soft than when mixed for moulding. Ram the cope A and frame B with this sand. Turn over and remove the frame B. Cut away all the sand remaining above the parting line C D and sleek off the surface of the same until it is made us smooth as possible. This leaves the pattern half imbedded in the sand of the cope A. Draw the pattern and finish the mould. The sand thus mixed with linseed oil will become as hard as a board. When dry it will form a perfect and serviceable follow board.
The method of using the follow board is to lay it face upward on. the floor as shown in Fig. 52. Put the pattern in position and the drag upon the cope as shown. The drag, of course, rests upon the cope at the parting fine C D. The frame B is not used. Ram the drag as described for ordinary work; turn the whole; remove the follow board; put on the cope and mm as in the case of simple or two-part patterns.