A bat lets you move a freshly thrown piece while leaving it on a supporting surface. It is particularly useful when lifting the soft pot itself would distort it. Choose the bat around that handling job, then check its attachment and drying-space requirements.
Follow the pot from wheel to shelf
A broad wet plate and a small practice cylinder create different handling problems. For the plate, carrying its support can be the sensible option. For repeated centering exercises that you immediately reclaim, several spare bats may provide little benefit.
Measure the shelf receiving the work, not just the wheel. Include clearance to lift a loaded bat without brushing the rim against the shelf above. The useful bat size is one that supports your form and has a protected place to stay.
Diameter, fitting and clearance are separate checks
A 12-inch bat is not defined by its pin spacing. Check the hole pattern, seating surface and thickness as well as the diameter. A bat can overhang a wheelhead yet fit an approved system; an apparently matching diameter can have the wrong attachment.
Use the wheel manual for permitted combinations and pan clearance. If you already have several bats, note their actual measurements before selecting another wheel. Do not count them as transferable equipment until the new fitting is confirmed.
Material changes what happens after throwing
Speedball describes its wooden bats as moisture-absorbing and its plastic versions as an alternative for repeated use. Follow the care instructions for the material you choose. Neither material guarantees that a pot will release at a particular time or dry without cracking.
Watch the actual base and rim as a piece firms. A support that suits one clay body and form may require a different release routine for another. Keep the bat identified when comparing results so that a change of surface does not disappear from your notes.
How many bats are useful?
Count the pieces likely to remain on bats between sessions. If four pieces occupy four supports until the next day, another throwing session requires spare supports or a different production schedule. Shelf capacity limits that decision just as much as the price of a multipack.
Inspect a bat that rocks after cleaning it and setting it on a known flat surface. Look at the attachment holes too. A warped support or damaged fitting should be taken out of use; stacking material underneath without knowing the cause leaves the problem unresolved.
Questions about this topic
Do Speedball plastic bat colors have different properties?
Speedball says the colors have the same performance characteristics. Color can help identify batches or users.
Do I need a bat for every pot?
No. Its value is in supporting and moving the form you are making. Learn a suitable release method for the surface you use.