Porcelain is a delicate material that can easily crack or chip if handled roughly. Cracks and chips in porcelain items like plates, cups, figurines, and sinks can detract from their beauty and make them less functional. Fortunately, there are several good options for repairing cracked porcelain depending on the extent of the damage.
What causes cracks in porcelain?
There are a few common causes of cracks and chips in porcelain items:
- Dropping the item onto a hard surface
- Banging the item into other hard objects like countertops or sinks
- Exposing the porcelain to rapid temperature changes which can cause thermal shock
- Using abrasive cleaners or scouring pads which scratch the delicate glazed surface
- Putting porcelain in the dishwasher if it is not dishwasher-safe
- Stacking porcelain pieces tightly together so they knock against each other
Even hairline cracks that aren’t visible at first glance can lead to further cracking and damage over time. That’s why it’s important to repair any cracks or chips as soon as you notice them.
Should you repair porcelain cracks?
For fine porcelain items like china or heirloom pieces, it is often worth repairing any cracks or chips to retain the value and beauty of the item. However, minor flaws in utilitarian porcelain pieces like sinks or bathtubs may not require repair.
Here are some benefits of repairing cracked porcelain:
- Restore the appearance and structural integrity of the item
- Prevent cracks from worsening over time
- Allow you to keep using damaged porcelain pieces
- Maintain the value of precious items like antiques or china
- Provide a less costly solution than full replacement of the item
If the porcelain item has major structural damage or is dangerously cracked, replacement may be the best option. But for most minor cracks and chips, repairs can often breathe new life into porcelain.
What are the best porcelain repair methods?
There are a variety of products available for DIY porcelain crack repair. The best method for your piece will depend on the size and location of the damage. Here are some of the most effective options:
Porcelain repair epoxy
Two-part epoxy adhesives specially formulated for porcelain can permanently fill cracks and chips. These are applied by mixing separate resin and hardener components together and filling the crack. After curing, the epoxy sands smooth for an invisible repair. Epoxy is ideal for cracks wider than a hairline.
Clear glue
For hairline cracks, a drop of clear-drying craft glue like Mod Podge can be an easy fix. The thin glue is drawn into the crack via capillary action. Once dry, the glue is transparent and nearly invisible.
Porcelain bonding agent
Bonding agents contain an acrylic polymer mixed with a solvent that softly bonds cracked edges together. After application, baking the porcelain at 200°F polymerizes the acrylic into a hard seal. Bonding agents work well for hairline cracks and minor chips.
Two-part porcelain filler
Filler products contain porcelain powders that can be mixed with a liquid catalyst to form a putty. The putty fills chips and adheres fragments together after hardening. The filler sands smooth and is paintable to match the surrounding porcelain.
Porcelain crackle repair kits
For treating multiple hairline heat cracks, specialized crackle repair kits infuse a bonding agent into the lines via vacuum. This stabilizes the cracks to prevent further damage. The clear bonding resin is designed to maintain the original crackled glaze appearance.
Professional restoration
For very valuable antique and ceramic pieces, professional restoration may be warranted to ensure optimal repairs. Experts have specialized tools and adhesives to bond cracks and replace missing fragments.
How to repair hairline cracks
Hairline cracks less than 1 mm wide often need only a simple adhesive method. Here are some tips for repairing hairline cracks:
- Clean the crack thoroughly to remove any dirt or debris.
- Select a repair product designed for hairline cracks like clear glue or porcelain bonding agent.
- For glue, use a toothpick to place a tiny drop directly into the crack.
- Apply bonding agent along the length of the crack according to the product instructions.
- Allow the adhesive to fully cure, usually around 24 hours.
- Smooth away any excess dried adhesive with fine sandpaper.
How to repair wider cracks and chips
For more significant cracks wider than 1 mm or chips with missing fragments, a filler product works better than simple glue. Here is a general procedure for wider crack repairs:
- Clean out the damaged area thoroughly and remove any loose fragments.
- Choose an appropriate filler product like epoxy, two-part filler, or porcelain bonding putty.
- Mix the filler according to package directions. Work quickly before the product starts curing.
- Press the putty firmly into the crack or missing chip, overfilling slightly.
- Allow the filler to fully cure and harden overnight.
- Sand and smooth the filled area to level with the surrounding surface.
- Use porcelain paints or markers for final color matching if needed.
Tips for an invisible porcelain repair
With care and patience, repaired cracks and chips in porcelain can be nearly undetectable. Here are some tips for a seamless finish:
- Take your time cleaning and preparing the damaged area before applying any filler.
- Make sure to fill slightly higher than the surrounding level to allow for sanding down.
- Cure fillers fully before sanding to prevent dragging uncured material.
- Use a fine sandpaper around 400 grit to smoothly blend the edges.
- Match colors with paints or markers designed for porcelain.
- Consider adding a porcelain sealer for added protection.
Preventing cracks when using repaired porcelain
To avoid new cracks after repairs, be gentle with restored porcelain items. Follow these precautions:
- Avoid extreme temperature changes like freezer to oven.
- Don’t put repaired pieces in the dishwasher unless labeled dishwasher-safe.
- Hand wash gently with non-abrasive cleaners.
- Pad cabinets and drawers to prevent hard impacts.
- Use placemats and padded tray protectors during serving.
- Separate stacked items with soft dividers.
When to avoid DIY repairs
While many cracks and chips can be repaired at home, some cases call for professional help. Avoid DIY repairs if:
- The piece is seriously structurally damaged.
- Large sections are loose or missing.
- The crack encompasses a large area or affects stability.
- There are multiple complex cracks.
- You need to match ornate decorative finishes.
- The item has major sentimental or monetary value.
For severely damaged museum-quality antiques or precious family heirlooms, hire a professional porcelain restoration expert for repairs.
Conclusion
Repairing cracked porcelain extends the life and usability of damaged items. For most minor cracks and chips, effective foyer products can often be applied successfully with careful workmanship. While preventing cracks by handling porcelain gently is ideal, prompt repairs when damage does occur helps restore both the appearance and integrity of your valuable porcelain pieces.