# Centering the Inverted Pot

Unit: Trimming & Refining
Topic: Lugs & Giffin Grips
URL: https://claybook.studio/learn/centering-the-inverted-pot/

# Getting It True Before You Cut

Whether you use lugs or a Giffin Grip, the pot must be centered before you start trimming. An off-center pot means the trimming tool cuts deeply on one side and barely touches the other, leaving an uneven foot ring.

## Centering with Lugs

1.  Set the pot upside down onto the lugs. Press it down gently; you should feel a slight resistance as the lugs grip.
2.  Spin the wheel slowly and watch the base of the pot. Does it wobble side to side?
3.  If it wobbles, tap the pot gently on the high side (the side that swings toward you) while the wheel spins. Use a fingertip tap, not a push.
4.  Repeat until the base appears still. Confirm by resting a fingertip lightly against the side of the pot: you should feel no bumping.

## Centering with a Giffin Grip

The Giffin Grip centres automatically as you tighten the arms. Tighten gently; overtightening can crack a leather-hard rim. Spin the wheel to confirm the pot is true before starting.

## The Off-Center Test

Place a finger or trimming tool just touching the side of the pot as it spins. If you hear or feel an intermittent click or tap (one contact per revolution), the pot is off-center. Keep adjusting until contact is constant and smooth.

## Pro Tip

Always check centering again after you begin trimming. The vibration of cutting can sometimes shift the pot slightly, especially with clay lugs.

## Centering Verification Loop
Use this loop before and during trimming:
* Spin slowly and observe side profile
* Tap high side if needed
* Recheck contact smoothness after first cuts

Re-verification prevents uneven foot rings.

## Did You Know?

Centering an inverted pot for trimming is essentially the same skill as centering clay on the wheel, and both rely on developing [muscle memory](https://en.wikipedia.org/wiki/Muscle_memory) through repetition. The sensitivity required to detect an off-center wobble by touch alone is a hallmark of experienced potters in the [studio pottery](https://en.wikipedia.org/wiki/Studio_pottery) tradition, where trimming is considered as important as throwing itself.

## Check your understanding

### Question 1: How do you correct an off-center pot held in clay lugs?

- [ ] A. Remove it and start again
- [x] B. Tap the pot gently on the high side while it spins
- [ ] C. Press the lugs harder against the pot
- [ ] D. Spin the wheel faster

Tip: Tap the pot gently on the high side with a fingertip while the wheel spins slowly until the wobble disappears.

### Question 2: How can you confirm the pot is truly centered before trimming?

- [ ] A. Look at it from above
- [x] B. Rest a fingertip against it and feel for a regular bump
- [ ] C. Measure the rim with a ruler
- [ ] D. Check the foot after trimming

Tip: Rest a fingertip lightly against the side as it spins. Constant smooth contact means centered; a regular tap or bump means off-center.