Fitting lids to pottery jars is one of those skills that can really elevate your work, turning a simple container into something special. It’s not just about slapping any lid on any jar; it’s about craftsmanship and understanding the unique properties of clay. Like any craft, it comes with its own set of challenges, but with a bit of know-how, you can create lidded pieces that are both beautiful and functional.
One of the biggest hurdles is dealing with shrinkage. Clay shrinks as it dries and again when it’s fired, and this can lead to lids that don’t quite fit right. To combat this, always use the same batch of clay for both the lid and the jar to ensure they shrink at the same rate. Keeping the thickness consistent in both pieces also helps them dry and fire evenly. And remember, it’s always better to make the lid slightly larger, giving you room to trim it down to the perfect fit. Warping is another common issue, especially during the drying or firing process. Uneven drying can cause the lid or jar to deform, so dry them slowly and evenly, maybe under some plastic or a damp cloth. When firing, make sure the lids are well-supported to keep their shape. Some potters even prefer to fire the lid and jar together to ensure they fit perfectly afterward.
As one potter put it, “I tried firing them separately but had some warping issues.”
You can read about their experience with firing lids and jars on this forum post.
Different lid designs each bring their own set of advantages. Flat lids are simple to make but might not offer the most secure seal. Domed lids add an elegant touch and extra space inside the jar but can be trickier to fit snugly. Flanged lids, with their extended lip that fits into the jar opening, provide a more secure fit, ideal for storage, although they require more precise crafting. Measuring accurately is key to a good fit. Calipers are your best friend here, helping you get those precise measurements of the jar opening. After the initial throwing, trim the lid to the exact fit you want, keeping in mind how the glaze will affect the final size. It’s a good idea to test the fit regularly as the clay dries, making any small adjustments along the way. Always be mindful of the glaze, too much and one potter warns,
“I have also made the fit too close and after the glaze they no longer fit.”
Always keep in mind how the glaze can affect the fit of your lids! You can read about other peoples experiences on the Ceramic Arts Daily forums. You may also want to read about Perfect Pottery Lids: A Potter’s Guide. Also remember to think about the design methods, perhaps you could use some tips for Perfecting Teapot Spouts: Design Methods and Avoiding Drips.
When it comes to fine-tuning the fit of a lid after firing, grinding and sanding are your go-to techniques. Wet sanding is particularly useful, as it minimizes dust and gives a smoother finish. Start with a coarser grit sandpaper to remove material and gradually move to finer grits to refine the surface. For more detailed work, diamond hand pads are excellent.
For removing larger amounts of material, a rotary tool with diamond bits can be a lifesaver. Safety is paramount, so always wear a dust mask and eye protection when sanding or grinding. Remember to let the tools do the work, without applying too much pressure, and keep checking the fit as you go.
For those looking to create an airtight seal, there are several options to consider. Rubber gaskets, especially those made from food-grade silicone, are a popular choice due to their flexibility and durability. Cork is another traditional material that can provide a tight seal, although it may not be suitable for long-term storage of liquids. Wax seals can also be used, especially for jams and preserves, but they can be brittle and prone to cracking. Whichever method you choose, the key is to design the lid and jar with the sealing material in mind, ensuring a snug fit and proper alignment.
With the right techniques and a bit of patience, you can create pottery jars with lids that not only look beautiful but also function perfectly, keeping their contents fresh and secure. Good luck!
