Removing a stud

Part 1. Preparation and safety

Objective

• Remove and replace a stud with a jam and drive nut or a stud remover.

Personal safety

Whenever you perform a task in the workshop you must use personal protective clothing and equipment that is appropriate for the task and which conforms to your local safety regulations and policies. Among other items, this may include:

• Work clothing - such as coveralls and steel-capped footwear
• Eye protection - such as safety glasses and face masks
• Ear protection - such as earmuffs and earplugs
• Hand protection - such as rubber gloves and barrier cream
• Respiratory equipment - such as face masks and valved respirators

If you are not certain what is appropriate or required, ask your supervisor.

Safety check

• Do not apply too much force to old and corroded studs. They may break if too much force is applied to them.
• Make sure that you understand and observe all legislative and personal safety procedures when carrying out the following tasks. If you are unsure of what these are, ask your supervisor.

Points to note

• Studs can be removed and refitted using two different methods:
  • Jam and drive nut
  • Stud remover
• The jam and drive nut method is used when the stud is re-used because it does not damage the stud.

• Stud removers are used to remove damaged studs when jam and drive nuts cannot perform the task.
• The most common type of stud remover consists of a frame with two holes and a knurled offset movable set of jaws.
• The holes are two different sizes. When you slide the stud remover over the stud, select the hole that allows the jaw to have the best purchase.
• Measure the exposed length of the existing stud before removal.
• After the stud has been removed, compare it to the new one. They should be the same thread and pitch.
• When fitting the new stud, apply the correct thread coating compound. It may be thread locking compound or an anti-rusting agent.

Part 2: Step-by-step instruction

1. Use penetrating fluid
   If the stud is rusted in place, soak the base of the stud threads with penetrating fluid to remove the corrosion and make it easier to take out. If possible, let the penetrating fluid soak in overnight.
2. Measure the old stud
   Before working on the old stud, measure its exposed portion to verify the new stud is the same size. Note the measurement.
3. Install the ‘drive’ nut
   Find two nuts with the same size and thread as the old stud, and thread one of these all the way down to the bottom of the stud. This will be the ‘drive’ nut.
4. Install the ‘jam’ nut
   Thread the second nut all the way down until it sits on top of the drive nut. This second nut will be the ‘jam’ nut.
5. Tighten the 'jam' nut
   Secure an open-end wrench to the bottom “drive” nut and hold it in position. Then tighten the “jam” nut against the “drive nut” with a box or open-end wrench. The jam nut will now prevent the drive nut from moving.
6. Turn the ‘drive’ nut
   Use the open-end wrench to turn the bottom drive nut counter-clockwise. The drive nut applies the turning force to the stud and forces it to unscrew.
7. Remove the stud
   Continue to rotate the drive nut until the stud comes out.
8. Attach the stud remover
   If jam and drive nuts don’t budge the stud, you can use a stud remover. Slide the stud remover over the old stud and seat it flush with the surface of the component. Turn the jaws in a counter clockwise direction until the stud is held tight.
9. Turn counterclockwise
   Fit a wrench onto the stud remover and turn the wrench in a counter-clockwise direction. The stud remover will grip the stud and turn it. Continue to rotate the stud, using the wrench, until the stud comes out.
10. Inspect for damage
    Once you’ve removed the old stud, inspect the internal thread of the hole for any damage