Repair And Fix it

Shift rods are used in cars, trucks and motorcycles that have manual transmissions. A shift rod consists of two eye-bolts that are threaded onto a steel rod. As you change gears, the shift rod engages and disengages the clutch linkage. Shift rods are available in various lengths from auto parts stores, or you can have one cut to a custom length to fit your particular application. A die set may be used to cut threads on a blank or universal shift rod when the original is not available.

Instructions

1

Place the shift rod in a bench vise and secure it firmly. If the rod is chrome, place a shop towel around the shift rod before you tighten the vise to keep the rod from being scuffed.

2

Measure the internal threads of the eye-bolts with the thread gauge. The gauge will have a mark on its side to show which size thread will need to be cut.

3

Select the correct size die and install it in the die wrench. Secure the die by tightening the two screws in the wrench to hold it in place.

4

Apply cutting fluid to the area that is being threaded. Place the die wrench on top, perpendicular to the shift rod. Turn the wrench clockwise while pushing down. For every full turn, back the wrench off one-half turn to remove burrs. Continue to turn the wrench until you have cut the thread the desired length.

5

Remove metal shavings and excess cutting oil from the shift rod with a shop towel. If cutting both ends of the shift rod, remove it from the vise and turn it over. Repeat Steps 1 through 4.

Thread damage commonly occurs when cutting bolts, making the bolts difficult to start in a nut or threaded hole. Bolts made of certain materials, such as stainless alloys, will have a tendency to gall and bind if the bolt threads are damaged during cutting operations. Preserve the shape and pitch of the threads -- particularly the starter thread -- to prevent the bolt from binding in the hole. Maintain the threads during cutting by using proper techniques and tools.

Instructions

1

Install a die of the proper diameter and pitch on the bolt to be cut. Thread the die all the way down to the bolt head or shoulder.

2

Install a nut of the proper diameter and pitch onto the bolt. Thread the nut down the bolt until the bottom edge of the nut is on the desired cut location.

3

Grasp the bolt firmly above the nut and brace your hand against a firm surface to hold the bolt steady for cutting. Cut the bolt off, using a hacksaw. Use the bottom edge of the nut as a guide to make certain the cut stays square and perpendicular to the bolt.

4

Remove the nut from the bolt.

5

Grind a 45-degree chamfer on the cut end of the bolt to remove any spurs from the starter thread, using a grinder. Do not grind the chamfer beyond the first thread.

6

Rotate the die off the bolt to clean up any remaining spurs and make certain the threads are correctly shaped.

7

Remove loose metal shavings from the bolt, using a chip brush.

According to Precote.com, liquid thread coating is the application of a sealant, lubricant or anti-corrosion chemical to the threads of screws, nuts and bolts. Liquid thread coatings are used by automotive manufacturers, the airline industry, railway companies, shipyards and nearly every manufacturing industry. Liquid thread coatings can be applied during the manufacturing process or after-market to the threads of screws, nuts and bolts.

Liquid Nylon

Liquid nylon provides a number of benefits when applied to part threads and works well on both iron and non-iron metal threads, such as steel, aluminum, brass and stainless steel threads. A thin layer of liquid nylon protects threads from wear, friction and corrosive elements and inhibits electrical conductivity. The nylon remains intact in both high heat and freezing temperatures.

Wax

Wax-based liquid thread coatings serve primarily as a thread lubricant. Wax-based liquid coatings are applied to nut, bolt and screw threads to make assembly smoother and to avoid cross-threading or sticking threads. The liquid wax is sprayed on the part or the part is dipped in the wax by a machine, or the wax can be applied by hand. New threaded parts may be coated with liquid wax lubricant at the end of the manufacturing process.

Teflon

Liquid Teflon is often applied to threaded parts as a sealant and to help reduce wear caused by friction. Liquid Teflon is typically used on screws, nuts and bolts that are subjected to vibration, such as those used in refrigeration units and manufacturing environments. Liquid Teflon thread lubrication applications may contain other chemicals, such as polytetrafluoroethylene that increase the efficiency of Teflon lubrication. Teflon is used on metal, plastic and fiberglass parts.

Fluoro-Carbon Coating

Liquid fluoro-carbon thread coatings prevent threads from damage during assembly of parts by lubricating the threads. Fluoro-carbon thread coating is often used on part threads if the final product will be painted before or after assembly. Once dry, the fluoro-carbon coating resists paint. Fluoro-carbon coatings also resist electroplated paints and primers.