Monarch Lathe Tailstock Repair (first attempt)

[@ED_T]

I've restored the tailstock taper on my lathe. First I tried with a reamer like you, but even though mine did make chips, the result was not good at all. I ended up building a toolpost grinder specifically to do the job. I've used it since for other projects but the toolpost grinder really is the way to go in my opinion. You can see it in use in my SK30 tool holder fixture video

[@samuelwiltzius]

I’ll check it out. I’m currently learning all I can about tool post grinders.

[@bgg_wrks]

The way I fixed a worn out drill press spindle was by using a hardend morsetaper tool shaft, of a tool I didn't needed anymore and some lapping compound, started with a corse one and moved to finer and finer compound. About 2 hours of lapping and it was back in useable condition.

[@samuelwiltzius]

I’ll have to look into this - though I may have too much material to remove to clean up my taper for this to be viable.

[@ArcAiN6]

1) take the tailstock quill out, chuck it in the lathe, and indicate it true. 2) affix a grinding post and grinder to your cross slide, and set the angle of the cross slide to match the taper of the MT4 3) cover the ways with an oiled cloth 4) Slowly move the small grinding wheel in and out of the taper, as you run the lathe on it's slowest speed. 5) Check results, ensure the taper is correct, and all surfaces have been cleaned up. 6) Clean the ways thuroughly to remove any dost and debris from the grinding process.

[@samuelwiltzius]

That is a great plan. I’ve been looking into tool post grinders and asking around locally. I plan to clean up the taper at some point; but it may be a little while.

[@dazaspc]

You could remove the quill from the tailstock, set it up on the lathe carriage with the dividing head and use a grind stone mounted in the spindle of the lathe? It would knock off the high spots well enough to then use a shaped lap? Alternatively you could machine out the taper and install a bush that was soft enough to ream? I have repaired one in the past that had been taken to deep by doing this. However it's a very much last resort quick fix.

[@kudosjeg]

Isn't the your falure due to the fact that the tailstock is harder than your reamer. I was under the impression that people use a grinder for the tailestock and not a reamer. However, I highly enjoyed watching your professional process in the video. The air bearing sharpening process was extremely fun to watch.

[@samuelwiltzius]

Totally my failure. Monarch hardened just about everything on this lathe - I should have known. I will look into a tool post grinder eventually and I’ll revisit this.

[@jameshunter4083]

The sides of the reamer don't cut, it's just the chamfers of the end face that cut, that's why it's not cleaning up.

[@samuelwiltzius]

On a chucking reamer yes, tapered reamers are a bit different.