Page 394 - THREADING CATALOG

USER GUIDE
TAPS General Recommendations (Regrinding)

Maintenance Picture 4
It is important to periodically regrind the worn tap.
This is to avoid permanent damage or even tool breakage.
The Grinding Wheels
The structure and grain of grinding wheels must
be appropriate for the tap to be resharpened.

Taps for Cast Iron
Taps used on cast iron can rarely be resharpened, as
it is very abrasive and tends to wear the flank in such
a manner that it becomes grossly out of tolerance.
ϕ
Taps for Aluminun
After regrinding it is advisable to remove
the steel burrs with a wire brush.
Picture 5
Tap Inspection flank wear
It is important to inspect the tap after regrinding
to ensure that all of the dimensions and angles
have remained according to the specifications.
chamfer
Controls (tests)
Once the tap is resharpened, it is always
best to test it to correctly obtain the same
threads as when the tap was new.
• The chamfer must be perfectly on axis in order to avoid part to be new chamfer
the effects of picture 6. cut away
The cutters must have correct divisions.
• The results of resharpening with an incorrect Picture 6 Picture 7
division is shown in picture 7.
• The length and number of threads in chamfer must a
be precisely identical to those of the new tap.
3
b
Picture 1 Picture 2

2 4

1
β γ

chamfer out of center incorrect division-cutters
not concentric
Picture 3
γ

X

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