TABLE 4.
Results of performance testing of re-created products
| Joint System Cement | Ready-Mix | |||
|---|---|---|---|---|
| Test | Specified | Measured | Specified | Measured |
| Working consistency (estimated amount of water as a percentage of dry ingredients) | 63−67 | 65 | 53−56 | 60 |
| Alkalinity | 8.8−9.2 | 9.1 | NS | 8.9 |
| Working properties | Plastic, buttery working and free of grit or coarse particles | Smooth, plastic, buttery, no grit or particles, feathers well, sheers well | (M-971) Filler shall be very heavily bodied and possess fair plasticity. It shall be free of any coarse, gritty or undispersed particles. | Heavy-bodied with fair plasticity |
| (M971/974) Compound shall be plastic, buttery working and free of any coarse, gritty or undispersed particles | Very smooth, plastic, buttery, little grit or particles, feathers well | |||
| Bonding properties | After compound has dried, tape shall delaminate when peeled back | Minimal delamination, approximately 5%−10% | Tape shall show at least 75% fiber tear when delaminated | Minimal delamination, approximately 5%−10% |
| Crack resistance | At most, only a couple of small cracks in the wedge | No cracks | There shall be no large fissure cracks in the wedge, and no cracks in the thin section | One deep fissure in wedge, no cracks in thin section |
| Color | Neutral | Off-white | White | White |
| Viscosity (BU) | NS | 565 | 580 ± 20 | 580 |
Note. NS = not specified, BU = Brabender units.