Repair broken Spindle on an Orbit 12" OR-1458

[Driveslayer45]

I picked up a busted Orbit DP off Facebook, the spindle is broken at the slot to insert the tool wedge. this has the MT2 spindle. It appears to be similar to Grizzly and Jet models, BUT .. the spindles appear to be discontinued on all of them.. so my question:

Are DP spindles heat treated?

I can cut off the broken end and rebuild the shaft easy enough. A set of MT2 reamers is only $21 on Amazon. What i don't know is if i do that does it need to be hardened?

Thanks

 

[Superburban]

I would bet the spline section is treated, but the MT 2 taper is not. But that is just my thinking, I never checked any to see.

A file will easily tell you if it is heat treated. Any idea how it broke? if it is from a side impact, or stuck chuck, the runout may be too much. If the runout is acceptable, how about installing an MT2 adapter, and pinning it in place. To me, it does not look like you will have enough meat to ream out enough to make a full MY2 hole.

The other thought is to get something with the female MT2 taper, and turn both your spindle shaft, and tha adapter down so the taper will be a press fit on the old shaft, then pin them together.

 

[Driveslayer45]

I am not sure how it broke, the overall machine is kinda beat up, bit for what I paid for it i felt it was worth a gamble. I am thinking of doing what you suggest, cut the broke end off, bore out a section the cut a replacement piece to fit and press / sweat together, recutting a new mt2, or just cutting a jt33 taper and installing a chuck

 

[Superburban]

If you do not intend to change the chuck, I would go with just turning the end to a Jt33, ans be done with it. A lot less room for error. I was thinking you wanted the MT2.

 

[Driveslayer45]

No, the only reason to make it mt2 is to make it factory. Best I can tell it's not a high dollar / value machine so I'm not sure if it's worth the trouble of cutting the mt2

 

[Driveslayer45]

ok, i dont have pictures, although i wish i would have taken some. i cut the broken shaft off above the break, drilled and bored a 1/2 hole, 1" deep. machines down a shaft with a male protrusion .503", pressed together then welded the seam. put it back is the lathe, faced, drilled for a live center and cut the new section to size. I ordered an MT2 reamer from Amazon, cut a new taper, tossed in the mill and cut a new tool slot (damn i should have taken pictures) for the wedge. and put it back together. .003 run out at the MT2 bore, which is suspect is machine bearings.

I did not have an MT2 arbor and chuck i could spare, but i had a old Mt3 with 1/2 chuck from an old lathe, so i mounted that in the lathe by a drill blank mounted in the chuck, put the arbor on the live center, set the compound to the angle and using a cordless drill proceeded to turn the taper. I cut the taper a little oversize, but it works well..

happy with that project .. i have got to start taking pictures....