Shear Gear with C-Clip Gearbox Protector | Fits AMMCO Brake Lathes | Part #7996

Brake Lathe Details

Replacement shear gear with locking C-clip for AMMCO bench brake lathes. Designed as a sacrificial drive component that intentionally fails under excessive load, the shear gear breaks before damage reaches the lathe's main gearbox. This protects the more expensive internal drive train from operator overload, jammed workpieces, or improper feed rates. The integrated C-clip retains the gear on its shaft and prevents lateral drift during normal operation.

Part #: 7996
Function: Sacrificial drive gear, gearbox protection
Includes: Shear gear with retaining C-clip
Lathe compatibility: AMMCO bench brake lathes
Replaces: OEM 7996 sacrificial gear in stock AMMCO drive assemblies
When to replace: After any drive overload, jammed cut, or visible tooth damage
Stocking recommendation: Keep one or two in shop inventory at all times

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Frequently Asked Questions (FAQs)

Why is the gear made of plastic instead of metal?

The gear is intentionally designed to be the weakest link in the drive system. If it were made of metal, an accidental jam or over-travel would force the internal steel gears of the gearbox to break instead. Replacing a $10 plastic gear takes 5 minutes; rebuilding a gearbox costs hundreds of dollars and results in days of lost revenue.

Can I install this myself?

Absolutely. It is located behind a small metal cover on the side of the feed box. Usually, all you need is a flat-head screwdriver to remove the cover and needle-nose pliers to swap the C-clip and gear. It is one of the easiest repairs you can perform on an Ammco lathe.

Why should I keep a "3-pack" or "5-pack" in the shop?

Because they are sacrificial, they will break eventually. If a shear gear pops at 4 PM on a Friday and you don't have a spare, you can't finish that brake job. Most professional shops keep at least 2

Is the 7996 different from the 7995 shear gear?

Yes. While they look similar, the 7996 is the primary gear for the cross-feed mechanism (rotors). The 7995 is typically used in the lead screw/spindle feed (drums) on certain models. Always verify which feed box has stopped moving before ordering.

What causes a shear gear to break?

'-Operator Error: Driving the tool bits into the hub or the lathe's own housing.
-Heavy Cuts: Attempting to remove too much material in a single pass.
-Lack of Maintenance: If the slide ways aren't lubricated, the friction can become high enough to "pop" the gear.
-Jams: Metallic shavings or debris getting caught in the cross-feed screw.