Connecting-Rod Straps To Refitting Rods

Place the gib and key in the strap to prevent it from warping, and heat the crown end of the strap to a bright red; on taking it from the fire, remove the scale by lightly filing with a coarse file; then plunge the strap to nearly half the thickness of the crown in water, and after holding it there for about ten seconds, slowly immerse the remainder of the strap in the water, and withdraw when quite cold. It will be found to have closed along its whole length, although mostly at the points.

How To Soften Copper Or Brass

Heat to a low red heat, and plunge in salt water.

How To Harden Copper

Copper may be slightly hardened by closing the grain. This can be done by lightly hammering its surface with a round pene-hammer.

How To True Corundum-Wheels

The wheel being adjusted in the lathe, revolve it very fast, holding a piece of corundum-stone against the uneven or wabbling surface. In a short time, the piece will melt and unite itself to the wheel, so as to make the latter perfectly true.

How To Clean Greasy Cotton-Waste

Boil it in a strong solution of common soda in water, and save the resultant soapy liquid to keep your drills and reamers wet when boring iron.

Riveting Crank-Pins

In riveting over the end of a crank-pin, apply the hammer most around the outer circumference and least toward the centre; this will prevent the riveted end from splitting.

How To Prepare Fine Emery For Grinding Purposes

When no fine emery is at hand, place coarse emery upon an iron block or plate, and hammer it well with the face end of the hammer; after which, grind it by abrasion with the hammer face.

Speed Of Emery-Wheels

A 6-inch emery-wheel should make about 2400 revolutions per minute; an 8-inch, 1800; a 12-inch, 1200.

Engine-Room Chairs

Good chairs for engine-room or factory use are easily made of light gas-pipe.

How To Clean Grease From Bolts

Moisten in benzine, roll in sawdust, and brush afterward.

Care Of Grindstones

These should never be left in the sunlight, or with one side standing in water, since heat evaporates the water in the stone, leaving it harsh and hard, while saturation softens it. The grindstone is a self-sharpening tool; and after being turned in one direction for some time (if a hard stone), the motion should be reversed. Sand of the right grit applied occasionally to a hard stone will improve it.

Selecting Grindstones

When you get a stone that suits your purpose, send a sample to the dealer to select by; a half-ounce sample is enough, and can be sent by mail.

How To True A Carpenter's Grindstone

Use a 3/4-inch bar of iron, or a gas-pipe, for a turning tool, held below the centre of the, stone.

How To Prevent Cracking Of Metals While Hardening

Heat the water as hot as bearable to the hands, dip the metal endwise, and immerse' with the thickest part of the metal downward. When fully immersed, hold the metal still until it is quite cold.