A crude but universal installer test in which a handful of freshly mixed castable is squeezed into a ball and tossed a short distance up and caught. Correct consistency holds together, shows a slight sheen and sags a little; a crumbly ball means too dry, while one that slumps flat and leaves water on the palm means too wet. It backs up the measured water addition on the mix sheet.
Ball-in-hand test says it's too wet, dump that batch and weigh the water this time.
Also heard as
- ball test
- ball in hand
Related terms
Castable
Dry refractory mix of aggregate, fines and binder that is mixed with water and poured or pumped like concrete.
Stinger
Shop name for the immersion vibrator head pushed into fresh castable to consolidate it.
Plastic refractory
Moist, workable refractory delivered ready to use and pounded into place with a pneumatic rammer.