We have specially ordered these for applications where regular tapered and
hardened arbor cannot be used. However, the straight shank portion is soft.
Hence, they can be machined to adapt for special applications.
Taper portion is hardened and ground.
Taper end is threaded to fit 3/8" x 16 TPI drawbar.
Size: MT3 - 1"
I bought one MT3 and one MT2 for aligning the tails stocks in my two lathes. Just turn a piece of scrap to 1” in the head stock chuck and place the stub arbor in the tail stock. Use a dial indicator to measure the horizontal deviation between the two and adjust the tail stock until the deviation is zero. The lathe is now aligned.
I have also use the stub arbors as templates to set up the compound slide angle for cutting Morse tapers on the lathes. Chuck the 1” end of the stub arbor in the three-jaw chuck or better still in a collet chuck if you have one, and use a dial indicator or a test indicator to align the angle of the compound. Just make sure that your indicator is measuring dead on the centerline.
I ordered an MT3 and an MT2 stub arbor as tools to align the tailstock on my very accurate lathe. I was amazed how concentric these things are right out of the box. My original plan was to machine the stub ends to the same diameter so I could compare the headstock to the tailstock... but the stubs were so accurate and concentric right out of the box, I didn't need to. I have about 0.00015" spindle TIR on my lathe -- and it gets no worse with these arbors. Amazing for the price. I have 3 of these and the stubs all measure .9999" exactly. Amazing. Mine are Groz brand -- made in India, not China.