Re: Greg's Logan 820 Restoration: Spindle Reassembly
Time to reassemble the spindle.
Attn: Mister Ed - you commented on my last posting about oil holes. The hole visible in the large pulley is not the oil hole, it's for the bull gear plunger. The small pulley has two tapped holes, one marked for the "oil" setscrew, and another unmarked one. This is as shown on the parts diagram on the LA-27-1 Headstock Assembly to S/N 32777 parts diagram.
But I have questions about that unmarked one:
What is its purpose and is it supposed to be tight against the spindle or not? Mine was not tight, and I saw no scarring on the spindle to indicate anything had been tightened in the area. When the back gear is engaged, this pulley needs to spin on the spindle, so setscrewing tight would seem to be dead wrong.
What is the correct type and size of set screw? The diagram makes it look like a dog point, but my machine had a plain setscrew. If indeed, it does not need to go tight, then that is fine. Would a dog point make any difference?
Yesterday I reassembled the spindle into the headstock. Remember, this is an early serial number model 820, there are differences in the later S/N's and as I understand from other's postings, the Logan 200 is quite similar, but with some obvious differences. Your mileage will vary!
First image shows the parts ready to go together: headstock, spindle with woodruff key and main bearing, bull gear, cone pulley, and spacer. In the back is the replacement bearing for the left side, and a custom bearing driver for it, made from a chunk of 4x4.
This went together much easier than it came apart! As they say, for reassembly, simply reverse the procedure! Inserted the spindle from the right, sliding the bull gear, cone pulley and spacer onto the shaft. I drove the bearing into the headstock using a PVC pipe coupler (3.5" OD) to bear against the bearing's retaining ring. In the next two pictures, first, you see the bearing in the headstock, with the retaining ring now up against the casting. The second shows the end cap in place, with its 4 fillister head screws. Again, this had been commented upon in a recent posting. My lathe certainly has 4 holes and 4 screws. But according to the parts manual for my serial number, it should only have 3.
Next steps: slide the bull gear to the right onto its woodruff key. This was easy, using the cone pulley like a slide hammer to tap it into place. (I wish I had measured the exact distance between the bull gear and the casting; I think I have it right, we shall see when I put the back gears back in.)
Then tighten the bull gear's setscrew and insert the two setscrews into the small cone pulley -- yeah, the oil screw and the mystery screw (left loose) discussed above.
Before starting this restoration, I've had a problem with seeing oil on the pulley almost every time I open the cover to change belt positions. Apparently it is being flung back through the setscrew threads by centrifugal forces while running. Oil and leather belting is not a good combination. I will try a new setscrew. Does anybody have ideas on this? Maybe a bit Teflon pipe tape or silicon caulk on the threads?
Now the left side bearing and related parts. I had damaged the left bearing during the teardown. now with my custom wooden bearing driver, which will bear against both the inner and outer races, I should be able to safely install the replacement. First, insert a bearing cover, then the bearing, tapping with the wooden tool, then the outer bearing cover. It worked perfectly.
And the final steps: another spacer, the woodruff key and gear, and the retaining collar.
About that collar, as the photo shows, one needs a special spanner to properly loosen/tighten it. I couldn't find one, so resorted to hammer/punch and pipe wrench. This somewhat scarred collar will work for now, but once the lathe is operational again, I plan to make a replacement (unless I can find one easily. Maybe I'll make that spanner too, or machine flats for wrench.
Next task, install the back gear. I have already slotted the end of the backgears' eccentric shaft to facilitate the adjustment of the gear mesh.
Greg