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“In one sense the great struggle into which we have now entered is an American struggle, because it is in defense of American honor and American rights, but it is something even greater than that: it is a world struggle.

“It is the struggle of men who love liberty everywhere, and in this cause America will show herself greater than ever because she will rise to a greater thing.

“We are saying to all mankind that we didn't set this government up so that we might have a selfish and separate liberty.

“We are now ready to come to its assistance and to fight out upon the fields of the world the cause of human liberty. In this thing, America attains her full dignity and full fruition of her great purpose.”

President Wilson in a memorial address

May 30, 1917

CHICAGO

JUNE, 1917

The Development of the Molding Machine* The Hand Squeezer, the Simplest Molding Machine. Description of Types, Equipment and Method

of Operation.

The hand squeezer is the simplest molding machine. It is essentially a molder's bench equipped with a movable squeezer head usually made to swing out of the way while the operator is filling the flask. This head is brought down against the mold, thus squeezing the sand, by some form of toggle joint or by use of the rack and pinion. A hand lever operates either the rack and pinion or the toggle-joint type. This machine accomplishes in the single operation of squeezing what a molder does in several rammings. Even this molding machine, simple as it is, lessens hand labor, increases production and reduces costs.

Different kinds of Hand Squeezers Hand squeezers are built in stationary, portable and straddle-leg types. The portable type (Fig. 1) is equipped with wheels which permits it being easily moved about the foundry and makes a foundation of any kind unnecessary. This type can also be pushed along by the side of the sand heap as the floor is filled with molds.

The stationary type (Fig. 2) should have pieces 6" x 6" timber imbedded in the foundry floor upon which to rest, and should be fastened down by means of lag screws.

The straddle-leg type is made to straddle the sand heap and by dumping the molds and cutting the sand in a narrow windrow, the machine can be pushed along as the floor is filled up, saving considerable labor in carrying molds. The machine moves instead of the sand. This also saves labor in dumping the molds. In spite of these facts the stationary machine is preferred by a great many foundrymen.

*Bulletin No. 6, of the Committee on Foundry Methods of The National Founders' Association.

[graphic]

FIG. 1
Plain Hand Squeezer, Portable Type

Some hand squeezers have a vibrator attached to the table of the machine. This gives vibration similar to rapping a tub in hand molding in the brass foundry.

For special jobs, hand squeezers are built in different sizes and with varying distances between the strain rods. Machines are thus obtainable for nearly every job for which hand squeezers can be used.

Wall or Post Squeezer

Some hand squeezers are made to attach to a wall or post and some have a post to support the head and table (Fig. 3). These machines leave the floor space clear for sand.

[graphic][subsumed][merged small]

Duplex Squeezer Hand squeezers are also built to squeeze the cope and drag at one operation, the cope and drag being made side by side

FIG. 3

Post Squeezer (Fig. 4). The patterns are mounted on two plates, one for cope and one for drag, so laid out from the flask pins that the cope and drag match when placed together. These machines are operated entirely by hand power and without a vibrator if neither air nor electricity is available. One type operates by lowering the mold away from the pattern while another lifts the pattern away from the mold. While the pattern equipment on this type of hand squeezer costs more and there is a greater chance for shift to occur, still the production from this class of machines is large and great numbers are in use.

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