Pottery Rib for Mugs & Cups, Bubble Shaping Tool. Pick your size and color

Pottery rib for throwing triple bubble mugs and cups: three full, even rings stacked from rim to foot for a bold, playful profile. Choose your size and color! Available in six sizes from 4 to 6 inch (100–150 mm) ✨ DESIGNED FOR USE Holes for grip and for hanging on a pegboard Flat profile that works for left- and right-handed potters, just flip it over 📏 WHICH SIZE? Sizes are the rib's overall height. Relative to clay weight: 100–110 mm suits small cups (~450g) 120–130 mm suits everyday mugs (~500g) 140-150 mm suits tall mugs and tumblers (~600g) Clay shrinks as it dries and fires, so finished pots come out smaller than the rib. How much depends on your clay body. Want all six? Choose "Full set of 6 sizes" in the dropdown. 🏺 HOW TO USE - Throw your cylinder close to its final height first, then use the rib to refine the shape - Start with thicker walls, because shaping with the rib stretches and thins them - Keep the clay and the rib wet - Make an undercut at the base of the cylinder so you can place the foot of the rib into it - Support and push the wall from the inside with your other hand and let the rib shape the outside - Go slow but with confidence - Second passes are better than too much drag in the first pass 🔧 CARE Rinse off slip after use and let it dry before storing. 🚚 MADE & SHIPPING Designed and 3D printed by me in my home studio, where I use these ribs for my own mugs. Made to order in 3–5 days, plus delivery. Thank you for supporting an independent maker!