How to Use the Foredom® Duplex Adapter and Hammer

Courtesy of Foredom

Directions for Replacing Duplex Springs

Read Carefully--Disassembly requires All Counterclockwise Turns. You will need: 2 pairs of pliers, 1/16 inch diameter pin and a 3/16 inch open end wrench or needle nose pliers.
Remove handpiece adapter from both shaft and handpiece. This can be done with a sharp pull.

Unscrew the QD Sheath Connector from Duplex Cover Assembly using two pairs of pliers at points A and B, turning counterclockwise. This exposes the Slotted Shaft Connector.
Insert a 1/16 inch pin through the hole in the Duplex Axle. Holding pin, unscrew Slotted Shaft connector from axle, using a pair of pliers at point C turning counterclockwise.
Remove Retaining Ring from axle with needle nose pliers. Remove Washer.
Unscrew Duplex Cover from the Handpiece Tip using two pairs of pliers at points E and D, turning counterclockwise. This exposes the damaged Duplex Spring.
To remove the damaged spring: Inspect Duplex Key Tip at point F. Hold Duplex Key Tip on point F using a narrow pair of pliers above spring. With a second pair of pliers hold damaged spring, and pull while turning counterclockwise to remove it.
To remove axle from damaged spring: Insert a 1/16 inch pin through crosshole in axle. Remove spring as in Step 6 using a pair of pliers.
To install new spring: Put the new spring on the duplex axle first by pushing and turning it with the pliers counterclockwise. Be sure that the spring goes all the way to the shoulder of the axle (Point G).
Holding the Duplex Key Tip as described in Step 6, install the spring on the Duplex Key Tip by pushing and turning it with the pliers counterclockwise. Be sure that the spring goes all the way to the shoulder of the spindle (Point H).

IMPORTANT: Be sure to follow lubrication instructions (10, 11 and 12).
Lubrication of Duplex Spring
  • Apply a light film of Foredom Grease (MS10006) to the new duplex spring
  • Apply one drop of Foredom Oil (MS10005) to the axle
Reassemble by reversing procedures in Steps 2 through 5.
Attach duplex spring adapter to handpiece on one end and flexible shaft and sheath on the other being sure to align each key tip within the slot of each shaft connector. Run at low speed for one or two minutes to spread out grease and oil.

Safety tips: When using a Duplex Spring Adapter move the workpiece a bit further away from the motor to prevent sharp bends in the duplex spring.

Caution: To avoid frequent breakage or kinking of springs, Do Not subject this connection to unnecessarily sharp bends of more than a 45-degree angle. Do Not exert excessive pressure on work, but let the speed of the tool do the work. Do NOT use the Duplex Spring Adapter with large buffs more than 1 inches in diameter, aggressive burs or chisel handpieces.

Avoid jamming of bur, stone, drill, or other cutting tool in a cavity, slot, groove or hole in workpiece.

HP775 Duplex Spring Adapter is not covered by a warranty.

Foredom Duplex Spring Adapter

The Duplex Spring Adapter offers extra flexibility for intermittent light duty work. The spring drive is made of special steel, double wound, tubular construction with a protective flexible spring cover. It is an extension to a handpiece that easily connects between the back end of a handpiece and a flexible shaft. Remove the adapter for less delicate work.

Duplex Springs are subject to breakage and are not covered by warranty. We recommend that only experienced users of flex shaft tools and/or those whose work demands added flexibility use the adapter.

Attach Duplex Spring Adapter to handpiece on one end, and flexible shafting on the other, being sure to align each key tip within the slot of each shaft connector.

Instructions for Foredom Hammer Handpieces

Hammer Handpieces are supplied with an anvil point (HP10177). If anvil points are reshaped they must also be polished with a grinding wheel or sandpaper.

Operation: The H.15, 15D, and 15SJ handpieces can be operated at speeds from 0-5,000 RPM (or intermittently up to 7,500 RPM). Use at higher speeds will create excessive heat which will damage the handpiece.

Changing Points: Insert the pin through the cross hole in the anvil or carbide stylus point. Hold the handpiece firmly and unscrew the point in a counterclockwise direction. (Right hand thread.) A new point can be installed by threading it into the nosepiece and tightening it with the pin.

Adjusting Impact: The impact of the stroke is adjusted by turning the knurled ring on the handpiece--counterclockwise towards the tip for a lighter impact--and clockwise towards the back of the handpiece for a heavier impact.

Lubrication: Before disassembling nosepiece, be sure to clean off any dirt or other foreign matter to prevent it from falling inside the handpiece. Lubricate after every 10 hours of use. Apply no more than 2 drops of oil into the oiling hole located on the barrel of the handpiece and into the hole on the rear of the duplex spring connection of the H.15D.

Have a question regarding this project? Email Customer Service.

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