Page 737 - Iscar
P. 737

USER GUIDE
                                                                                                                     TAPS



            General Recommendations (Regrinding)

                Maintenance                                    Picture 6
                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                                                          Chamfer out
                Taps used on cast iron can rarely be resharpened, as                        of center
                it is very abrasive and tends to wear the flank in such
                a manner that it becomes grossly out of tolerance.

                Taps for Aluminun
                After regrinding it is advisable to remove
                the steel burrs with a wire brush.

                Tap Inspection
                It is important to inspect the tap after regrinding
                to ensure that all of the dimensions and angles
                have remained according to the specifications.
                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         Picture 7
                in order to avoid the effects of picture 6.                       a
                The cutters must have correct divisions.
              •  The results of resharpening with an
                incorrect division is shown in picture 7.                           3
              • The length and number of threads in chamfer must                                     b
                be precisely identical to those of the new tap.




                                                                    2                            4








                                                                                 1
                                                                                      γ
                                                                     Incorrect division-cutters not concentric


























                                                                                                                  733
                                                                                                                  733
   732   733   734   735   736   737   738   739   740   741   742