How Do You Stop Pottery From Cracking on the Wheel?

If your pottery keeps cracking while you’re throwing it on the wheel, the most common causes are uneven moisture, inconsistent wall thickness, excessive pressure, poor compression, or construction problems at the base and rim.

Cracks can appear while you’re throwing, shortly afterward as the piece begins to dry, or later during drying. Learning when and where the crack appears can help you identify the cause.

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Why Does Pottery Crack on the Wheel?

Wheel-thrown clay is constantly being compressed, stretched, and reshaped.

If different parts of the piece contain different amounts of moisture or are under different amounts of stress, the clay can respond unevenly. A crack may then appear at a weak point.

The good news is that many wheel-throwing cracks can be prevented by improving your clay preparation and technique.

1. Keep the Clay Moisture Consistent

Clay should have a reasonably consistent moisture level before you start throwing.

If the clay contains noticeably harder and softer areas, those areas can behave differently as you work.

Reclaimed clay is particularly important to prepare thoroughly because uneven moisture can make throwing more difficult.

If your clay feels unusually stiff in one area and soft in another, preparing it properly before throwing can help.

2. Don’t Use Excessive Water

Water is necessary for wheel throwing, but too much can create problems.

Repeatedly adding water can make the outer layers of the clay increasingly soft while other parts remain firmer. This can contribute to weakness and uneven drying later.

Use enough water to keep your hands moving comfortably, then remove excess water when appropriate.

The goal isn’t to keep the clay constantly wet. It’s to keep it workable.

3. Avoid Extremely Uneven Walls

Uneven wall thickness is a common source of problems.

A thick section and a very thin section won’t respond to drying in exactly the same way. Differences in moisture and shrinkage can create stress within the piece.

When throwing, aim for reasonably consistent walls.

You don’t need perfectly identical thickness everywhere, but avoid sudden transitions from very thick to extremely thin.

4. Compress the Bottom of the Pot

The bottom of a thrown pot deserves particular attention.

As you open the clay, the base can contain compressed and stretched areas. If the bottom isn’t properly compressed, cracks can sometimes develop as the piece dries.

After opening the clay, take time to compress and smooth the floor of the pot with an appropriate tool or finger technique.

Don’t repeatedly scrape the same area aggressively. The goal is controlled compression rather than excessive manipulation.

5. Watch for the Classic S-Crack

One common type of wheel-thrown crack is an S-crack, which appears on the bottom of a pot and often curves through the base.

S-cracks are frequently associated with problems involving the bottom of the vessel, including inadequate compression, uneven thickness, or stresses created during throwing and drying.

If you repeatedly get cracks in the same area at the bottom of your pots, pay particular attention to how you’re opening and compressing the base.

6. Don’t Make the Base Too Thick

A very thick floor can dry differently from the walls.

If the bottom contains much more clay than the rest of the vessel, it may take considerably longer to dry and can create uneven shrinkage.

Try to establish a reasonably consistent base thickness rather than leaving a large mass of clay at the bottom.

You still need enough clay for a stable base, especially if the piece will later be trimmed, but excessive thickness can create problems.

7. Don’t Make the Walls Extremely Thin Too Quickly

Thin pottery can be beautiful, but removing too much clay too quickly can weaken the form.

If you’re repeatedly thinning your walls until they are barely supporting themselves, small stresses can turn into cracks or collapses.

When learning, prioritize even and controlled walls rather than making every piece as thin as possible.

8. Be Careful With the Rim

The rim is one of the most frequently handled parts of a thrown pot.

Repeatedly squeezing, bending, compressing, and reshaping it can create weak areas.

Try to finish the rim deliberately rather than constantly changing it.

If the rim starts to crack, check whether it is becoming too dry, too thin, or being worked excessively.

9. Don’t Keep Throwing Once the Clay Becomes Too Soft

Long throwing sessions can gradually change the condition of the clay.

Water accumulates, the clay becomes softer, and repeated manipulation can weaken the form.

If your piece starts becoming noticeably soft or difficult to control, continuing to throw may create more problems.

Sometimes the best choice is to stop, remove excess water, and allow the clay to firm up before continuing.

10. Dry Your Pottery Slowly and Evenly

A crack that appears after you finish throwing isn’t necessarily caused by something you did during throwing.

Drying is a major part of the process.

If one part of the pot dries much faster than another, the difference in shrinkage can create stress and lead to cracks.

This is especially important with:

Thick bases
Large pots
Handles and attachments
Wide forms
Narrow openings
Pieces with uneven wall thickness

Dry pottery gradually and protect areas that are drying significantly faster than the rest.

11. Pay Attention to Attachments

If you’ve added a handle, foot, spout, decorative element, or other attachment, the join can become a weak point.

Attachments should be joined properly while the clay is compatible in moisture and firmness.

If one section is very wet while the other is considerably drier, the two pieces may shrink differently.

Good joining technique matters just as much as good throwing technique.

Where Is the Crack Appearing?

The location of the crack can give you a useful clue.

Crack in the Bottom

Look at your base thickness, compression, and opening technique.

Repeated bottom cracks may indicate an issue with how the base is being formed or dried.

Crack Around the Rim

Check the moisture of the rim and how much you’re manipulating it.

The rim can dry faster than thicker sections, especially if left exposed.

Crack in the Wall

Look for uneven thickness, excessive pressure, weak clay, or an area that has been repeatedly worked.

Crack at an Attachment

Check the joining technique and whether the two pieces had similar moisture levels when joined.

Can You Fix a Crack While the Clay Is Still Wet?

Sometimes.

If a small crack appears while the clay is still workable, you may be able to compress and smooth the area carefully.

However, simply smearing wet clay over a crack doesn’t guarantee that it will remain repaired during drying or firing.

If the crack is large or keeps reopening, it may be better to recycle the clay rather than spend a long time trying to rescue the form.

How to Prevent Cracks: A Beginner Checklist

Before removing your pot from the wheel, check:

Is the base reasonably even?
Have you compressed the bottom?
Are the walls reasonably consistent?
Is the rim stable?
Have you removed excess water?
Are there obvious weak spots?
Are any attachments properly joined?
Is the piece ready to dry gradually?

These small checks can prevent many problems later.

What If Your Pot Only Cracks While Drying?

If the pottery looks perfect when it leaves the wheel but develops cracks later, focus more closely on drying conditions, thickness, moisture differences, and construction.

Don’t automatically assume the wheel technique was the only problem.

Drying cracks and firing cracks are related but aren’t the same issue.

For example, a piece can be thrown perfectly and still crack because one part dries much faster than another.

How Is This Different From Cracking After Firing?

Cracks that appear after firing have a much wider range of possible causes, including firing conditions, thermal stress, clay-body compatibility, and glaze-related issues.

If your piece survives throwing and drying but cracks during or after firing, troubleshoot the firing stage separately.

Related Pottery Guides

For more help with wheel throwing and pottery problems:

Frequently Asked Questions

Why does my pottery crack at the bottom?

Bottom cracks can be related to uneven thickness, inadequate compression, a very thick base, or uneven drying. Repeated S-shaped cracks are particularly worth investigating.

Why does my clay crack when I pull it?

The clay may be too dry, uneven in moisture, overly manipulated, or subjected to excessive pressure. Check your clay condition and use controlled pressure.

Does too much water cause pottery to crack?

Too much water can weaken the clay during throwing and contribute to uneven drying. Use enough water for smooth movement without continually saturating the piece.

How do you prevent S-cracks in pottery?

Pay attention to how you open and compress the bottom of the pot, avoid leaving an excessively thick base, and dry the piece evenly.

Should pottery dry quickly after throwing?

Usually, no. Controlled, even drying is generally safer than rapid drying, particularly for thick or complicated forms.

Final Takeaway

Stopping pottery from cracking starts before the piece ever reaches the kiln.

Use clay with consistent moisture, avoid excessive water, keep your walls and base reasonably even, compress the bottom properly, and dry the finished piece gradually.

Most importantly, pay attention to where and when the crack appears. That clue can tell you whether the problem is coming from your throwing technique, the clay’s moisture, construction, or the drying process.

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