Pottery Soap Dispenser Threading Tool – Custom Fit for Clay Shrinkage V3 - 2.5 Thread

A simple threading tool developed for ceramists who want to make functional soap dispensers in clay.
Threading tools like this are often made of plaster and can usually be used 30–50 times before they start to crumble or lose their sharpness. This 3D-printed PLA version, on the other hand, can be used hundreds of times without changing its shape.

Precision and Tolerances: The V3 model has deeper, optimized grooves and sharper markings, allowing you to achieve the exact tolerance that suits your specific clay and pump.
Standard sizes: Fits 28/400 and 28/410 pump heads, which are the most commonly used for soap dispensers (28 mm).

Long lifespan: 150+ uses without problems.
Engraving: The shrinkage percentage is engraved directly on the tool, so you can always identify it easily.
Thread depth: The standard version is 2.5 turns.

How to find your shrinkage percentage
The manufacturer‘s figures can rarely stand alone. Shrinkage depends on the clay type, drying conditions, kiln, and firing curve. To ensure the right fit, you should always test yourself. Roll out a strip of clay about 10 cm long and measure the length very precisely. Fire the sample in the kiln, then measure again and calculate the difference in percentage. This way, you will find your exact shrinkage percentage for your clay and your conditions.

Color selection
By default, the threading tool comes in a random color. This is because I often print the tools together with other orders or use leftover filament from previous prints. This reduces waste and makes production more sustainable. The result can be a unique version, sometimes with a beautiful marbled or mottled look, each one unique. If you want a specific color, you can of course purchase one.

Material: Cornstarch and sugarcane
3D printed in PLA, which is a bio-based plastic material made from cornstarch and sugarcane. PLA (Polylactic Acid) is one of the most environmentally friendly types of plastic, as it is biodegradable under industrial conditions and made from renewable resources rather than oil.

Instructions for use
Use the tool when the clay is dry but not completely leather-hard. Removing it too early can cause the clay to crack, while removing it too late can cause the edge to break. Turn the threading tool 2–3 turns to create a functional thread, then carefully remove the tool and let the item dry completely. After firing, the pump head can be screwed directly into the thread. If this does not work for you, try adding cornstartch or mineral oil to the surface of the clay.

Tips & tricks
Avoid using the tool in very wet clay as this increases the risk of breakage. Many potters use cornstarch as a release agent, which burns away in the kiln without leaving any residue. Some have had success with a bit of mineral oil for easier release, where excess oil is trimmed off and the rest dries out.

Remember: Ceramics is always a bit unpredictable. What works in one workshop may not necessarily work in another. Do small test projects to find the method that works best for you.