SLITTING SAW ARBOR

(aug 2006)

..work done man

I bought two saws (3" and 5") on ebay and I now need the arbor for them... I chose to make  a Mt3 arbor that match perfectly the mt3 spindle of my x3 mill. Using a tapered arbor is better then use a collet plus the cylindrical arbor ...  less play, more accurate.

Like all my projects... a simple raw draw is what I need..

task start making the cup part, starting from a 30mm mild steel rod, turned down to the bore diameter of the saw (25.4 mm), and finished for 3 mm more on the chuck side.

then clamped on the vise, to made a 8mm hole for the M8 bolt

..positioned on the bandsaw to be cut as length required...

and back on the lathe to parting off the unwanted material, and to be sanded down with 1200 grit paper...

hop!  back again on the mill to machine the 16mm hole (8mm deep) for the M8 bolthead.

the cap is finished... now is time to start turning the main body: first step a long pass to  make it true at 29.00 mm

few quarters later and the taper is done and now it is turn to drill a pilot hole for the M8  thread and a bigger (but shorter) hole for the boring bar. (showed is 13mm hole)

The part is now turned 180° to machine the butt, after turning down to 19,00mm I made the pilot hole for the M12 thread.

Butt side (draw bar side) is done, now I need to bore the head to match perfectly the cap. I centered the workpiece on the chuck and I move the chuck on the spindle until I had a run out of 0.01 mm.     There is no way to center a piece on a 3jaws chuck.   My chuck body runs true (0.01) but the jaws are 0.02 to 0.08 mm out.   I am planning to mount a 4 jaws independent chuck that is more accurate, but at the moment I have to work with this 3 jaws one.

Again, the way to center a piece is to block the piece in the jaws, and the loose the chuck/spindle bolts to center the chuck whilst measuring on the workpiece what the workpiece is doing with a DTI, until 0.01 is achieved.

After all this I had my 0.01 run out and I was ready to play with my self made boring bar... (photo shows the finished hole)

then a 6.9mm hole and some threading action and the M8 bolt is perfect....

body finished !

It is all done now, body and cap are ready to be mounted...Note that the body bore depth size is a little more than the cap side side, this is to be able to mount different thickness saws. (about 0 to 8 mm, more could be unstable.)

top of the cap...

..just 1.8mm thick

and this is the 5" saw mounted on my X3 mill...

testing it..first cut.... it is working !!!!