Tangs not on centres

I'm fitting a DRO on my lathe tailstock, with my lathe the all my centers when fitted will foul up when on my clamp DRO fixing when I take them out. All drill chucks and M2, M3 reducers have a tang on the end and are ok when I take them out. My question is why are tangs not fitted to centers, I can understand if no tangs are fitted to drill chucks as it will give around 15mm more on the tailstock, but why not centers.

Edited By BOB BLACKSHAW on 25/03/2018 17:20:45

The tangs are used to drift out the taper via the slot cut in a drill press. Tailstocks do not have the slot and therefore the tang is deleted

If you need a little extra length on the centre to avoid fouling the DRO mounting. Cut some discs same dia as the centre small end from brass or even plastic and stick them on. Will be plenty strong enough to eject the centre.

John

As Journeyman - or drill, thread and insert a suitable bolt/screw/threaded bar to eject them earlier. Hardness might be deciding factor...

Edited By not done it yet on 25/03/2018 20:09:13

Use a smaller centre in a Morse taper adapter sleeve that has a tang. The adapter & centre are then ejected together. Arc sell a variety at very reasonable prices. (page 6 of the current number 10 catalogue. Usual disclaimer

Eric.

You can get screw in tangs.

I have a rotating centre that has a screw in button

Sure you can (Arc do them), but angs are only really needed where extraction is by wedge? Simple bolts are far cheaper for this problem?

Edited By not done it yet on 26/03/2018 11:10:48

All aboves a lot of faffing about, just buy what you want with MT tangs job done and self eject.
Will also have clearance for the clamp if the ram protrudes 1/4".

All my MK2 tangs are slotted and threaded M8 to have both worlds.

Martin

The scew in button gives you the extra retraction but avoids the 'fouling up' the original poster mentioned.