I have two tapping heads as described in the title that could do with a bit of TLC. They have a central shaft that is keyed so that it slides in and out smoothly and is spring loaded to a central position. It is driven by a stack of friction plates with alternate ones fixed to the body by dogs and the ones between the fixed plates rotate with the central shaft. The outer cover can be screwed further on or off to control the amount of friction between the plates to allow it to suit different thread requirements.

Despite searching on the WWW I have not found any servicing or operating instructions. What I am after is information on whether or not the friction plates should be cleaned and left dry or lubricated and if lubricated what with. At the moment the insides have gathered many years worth of cruddy muck that may or may not have been applied or may have just seeped in and may be coolant or lubricants.

So does anyone have experience of anything the same similar enough to suggest the correct course of action.

The driver for all this is that one of them was wound as tight as it would go and still slipped when cutting an M12 thread, the other one worked fine when it was tried instead.

Martin C

I tried the Saftap search option with no joy. Just found different models but no information. There is no oil port on the body, just a threaded hole for a locking grub screw. I'll take a few pictures to show what I have. in their current state.

Martin C