Replacing the spindle on Myford Speed 10

[nick]

It all started last week when I decided to order some 2MT collets for my lathe, so I didn't have to hold tooling in the chuck. The collets duly arrived and I made a drawbar to hold them firmly in place. Once the drawbar was made, I removed the chuck and inserted a collet, strange sez I, it shouldn't wobble like that........On close inspection, I found that the 2 morse taper socket had been bored parallel, how inconvenient, I mused....



The freshly made drawbar



Horror of horrors, the counterbored MT socket



A quick phonecall to Myfords in Mitholmroyd (where I bought the machine) produced a new spindle foc, which arrived the next day, no quibbling, just 'we will send a spindle straight away' can't beat that for service. So today I removed the old spindle, easier than I thought, I had looked at a thread elsewhere ( instructables I think) and the bloke who was doing it seemed to be making heavy weather of it so I was a tad aprehensive, he had to belt seven colours of ***** out of it to get the spindle out, using a big ammer and a lump of wood. I made a couple of drifts from aluminium to use instead of wood.

The drifts



So, first job, get rid of all the covers, so the doctor can see the patient, remove the banjo and changewheels and we are ready to go, the 25 tooth gear is removed next by undoing the little grubscrew and pulling the gear off. Next, unscrew the first locking collar, there is a grubscrew with a copper pellet (to protect thread on spindle) un do this and remove collar, next in line there is a spacer, remove that as well.......
Remove gear, collar and spacer....



Now we move inside the headstock, unscrew the grubscrew in the second locking collar, wind it out a good few turns so it will clear the flat on the spindle. Move along to the bullwheel (backgear) and undo the grubscrew, again, enough to clear flats. remove backgear cluster by un screwing the 5/16 whit nut on the end of the shaft and withdrawing it backwards. Now it is time ti attack with a hammer and knock the spindle out, as it turned out, half a dozen firm clouts and it was out, the grease cap on the front will pop off first.

Headstock components....


Ready to knock out the spindle....


All the parts were laid out on the bench in the order in which they were removed, ready to be thoroughly cleaned....


Final job of the day, remove the taper roller bearing from the chuck end of the old spindle, this needs to be done firmly but carefully, do not hit the bearing cage, only apply force to the solid inner part of the bearing or damage will occur. Ideally a press should be used, but I used a hammer and large pin punch, tapping opposite sides until it was free....

removing the taper roller bearing....
That's it for today, all the parts are soaking in degreaser, ready for re assembly tomorrow.

[Johnb]

Great progress. Thanks for posting.

[nick]

I forgot to mention earlier, there is a little Woodruf key keying the bullwheel to the spindle, keep an eye open for it......

[nick]

Cleaned all the components and fitted the taper roller bearing to the new spindle today. The bearing was tapped in to place with several sharp blows with a hammer and punch, applying force to opposite sides until it was hard up against the flange. You know it is there when the tone of the hammer changes. Finally, the brering was re packed with grease ready for re assembly tomorrow.

Change wheels and banjo


Headstock components....


Front of headstock cleaned up


Rear of headstock cleaned up..


Bearing nearly home


Nicely seated


And packed with grease....

[nick]

Job now finished. Reassembly is bascically the reverse of the dismantling sequence, paying particular attention to the following-a, the Woodruff key that keys  the bullwheel to the spindle, a bit fiddly It fell out of the key way a few times as I was tapping the spindle through. b, there needs to be a .005" clearance between the pulley cone and the second locking ring. c, don't forget to apply a light coating of lub. oil to the spindle before starting. Next job is to re fit the rear bearing ( now cleaned and re packed with grease), spacer and first locking ring, not forgetting the copper disk to protect the thread. Now it is time to adjust the endfloat. Lock the saddle and topslide and fit a magnetic stand and DTI, with the stylus resting on the flange. Tighten the first locking ring until you just have zero movement back and forth on the spindle. Recheck and adjust as necessary after running.

Assebbly in reverse order....


Use tailstock for support when tapping the rear bearing home....


Adjusting endfloat using DTI....


Now we come to fitting the 25T gear on the end of the spindle, once fitted it has to be drilled 4mm, using the join between spindle and gear as the center, this will be tapped 2BA for the securing grubscrew. It is a bit tricky, as the gear has to be held firmly to prevent it from trying to turn with the drill and jam up. The hole only needs to be about 1/4" deep. Finally, replace the grease caps, pump grease in until it oozes out either side of the bearings fit and adjust backgear cluster, making sure it lines up nicely with the bullwheel, reassemble the changewheels and banjo and she is ready for a test run.

Drilling the 25T gear...


Tapping 2BA


Grubscrew fitted


Started up and she ran very nicely, no nasty noises, infact, it is quieter than before, probably due to being thoroughly cleaned, greased and adjusted. Tried her at various speeds and all was good. Finally tried out the new drawbar and collet by doing a bit of flycutting, that too was a success, so all in all, a job well done. The above also applies of course, when changing the drive belt, except the spindle only needs to be withdrawn enough to replace the belt.

<a href="https://www.youtube.com/watch?v=jGyKKWzNM5I" target="_blank">http://www.youtube.com/watch?v=jGyKKWzNM5I</a>

<a href="https://www.youtube.com/watch?v=iF5Ecd3yDy8" target="_blank">http://www.youtube.com/watch?v=iF5Ecd3yDy8</a>