It is recommended that calibration of the test hammers be
checked regularly usually after about 2000
strokes.The James
Calibration Anvil
(W-C-7312) has been designed for just that purpose.
The Calibration Anvil weighs approximately 48 lbs.(22.23 kg) and should
be ordered separately.
Weight: 49 lbs (22.23 kg)
Physical Size: 9.5" H x 6.0" dia. (241 mm H x 152.4 mm dia.)
Shipping Weight: 51 lbs. (23.1 kg)
Hardness of Insert: 65-67 HRC
Q. My Test Hammer gives low or high
readings
A. Using the Calibration Test Anvil as a reference, find the rebound number on the Test Anvil. If the number is 80 +/- 2, the Hammer calibration is good. If not, the Hammer needs to be adjusted. With the impact plunger out, remove the rear cap on the Hammer. There is a
screw with two locking nuts in the cap. Adjust the screw position up or down accordingly, and recheck the rebound reading against the Calibration Test Anvil. When properly adjusted, be sure to tighten down the locking nuts in the cap. The Hammer is now ready to be used again.
Q. What if I have a Low Impact Test Hammer (W-M-255)
A. The Low Impact Test Hammer is calibrated in a similar way. The rebound number for this Hammer should be 75 +/- 2 on the Calibration Test Anvil.