Technical Info - Test Cases

Some results of the EDtapper performances:

Copper electrode on hardened steel
M5 thread to depth of 8mm takes 12minutes (roughness 5.2 Ra)
M10 thread to depth of 16 mm takes 18minutes (roughness 6 Ra)
M12 thread to depth of 20mm made by 2 steps:
Coarse: 25 minutes (roughness 6.8 Ra) – and then
Fine:  6 minutes (roughness 4.8 Ra)

similar results in accordance for:
NF10-32 to depth of 0.3”
NC3/8 to depth of 0.625”
NC1/2 to depth of .75”

Copper electrode on carbide endmill.

M6 x 1  male thread* (similar to NF1/4) on 6mm shank made in 2 steps:
1. coarse takes 50 minutes but the thread profile was not full due to electrode tips wear.
2. fine takes 40 minutes (roughness 2.24 Ra) .

As it can be seen work duration is much longer than on steel and electrode wear also higher.
Modern machines have exact adjustable conditions for carbide etching.