Modelling what might have been in southeast BC and northwest Wasington

Lathe saga

I control my track switches with a simple homemade toggle switch mechanism plus micro switches for the frog power. These are operated as simple push-pull using wooden dowels. The front end of the dowel passes through a plastic PVC pipe end cap, so that they are flush with the fascia. I got the idea from Jim Petro in Reno Nevada a number of years back when I operated on his layout during a PCR convention.

The end caps need a bit of work to prepare them for mounting. They have raised lettering on the face that I like to smooth off, and they need a hole drilled in the middle. Plus, I like to roughen up the outer surface using sandpaper so that the glue will stick better. All three operations are easily done on the lathe.

As we extended the fascia arouund through to Carson, I needed a bunch more of these prepared for installation. So, over to my trusty lathe. I used it to clean up about four or five of the caps without a problem, but half-way through the next one, it just stopped suddenly with the belt slipping. Huh, what happened? A quick check with the power off showed the the spindle had frozen solid and simply would not turn. Oh, oh.

Many years ago I was very fortunate to buy the 10″ metal lathe from a friend’s father who had worked for Boeing as a machinist. His hobby had been home-built aircraft of his own design, and he had designed his house with enough room in the basement to assemble them, but I digress….

Just after I purchased the lathe, I disassembled, cleaned, lubricated, and reassembled everything on it except the headstock, as I could see no easy way to do so and everything seemed to be running fine. Some years later, I was able to buy a copy of the user manual for the lathe and it included instructions on how to remove the spindle, only “if it was absolutely necessary”. Well, it now was and I really had nothing to lose, so I gave it a shot. It came out very easily, once you know what to do, which way to unscrew things, and where to apply pressure. The problem was immediately obvious in that the very old grease had simply solidified and jammed the ball bearings. The manual said the the spindle bearings were factory lubed with grease that was supposed to last the life of the machine, but I doubt they were thinking 73 years back then! (It was made in 1946.)

The seized spindle front bearing with hardened 73 year old gunk.
The rear bearing with who knows what sealed inside.

So…. a simple job, clean out the bearings, repack them with fresh grease, reinstall, and away we go! Or not.

I dunked the bearings in some solvent overnight, and lo and behold the next morning I could work it a bit and get it to rotate. It felt like there were no broken ball bearings, so that was a start.

I checked it later that day, and it was even looser, and the solvent was getting darker. My plan was to just let it sit and soak while I headed to California for the conventions and clean out the gunk when I returned. Into a 5 gallon pail it went to minimize fumes, and I left it in the garage. I removed the rear bearing and it looked to be pretty dirty also, so it was put into another tray for the long soak.

Fast forward a couple of weeks… Not what I had hoped for. While both bearings turned quite freely, they were still full of lots of the hardened grease gunk. So much for soaking in solvent. Alright, I have other solvents, maybe one of them would do the trick? Fast forward again through many frustrating days of experimentation, but nothing seemed to dissolve the mess. I kept researching online to see what would dissolve old grease, and trying everything they said should work. I tried solvent, kerosene, alcohol, naphtha, xylene, lacquer thinner, and brake parts cleaner. Nothing would touch the stuff. (Fortunately it was summer and I could do all of this outside.) More research into grease itself. It seems that they add a form of soap to oil to form grease. It thickens it and makes it stick to things. So, I thought, maybe all of the oil has gone away and I am really dealing with dried hard soap? In desperation, I put a small chunk of the hard stuff into a strong mixture of Dawn dishwashing liquid, and low and behold, it completely disappeared before my eyes in a matter of seconds! Wow, after all of the trials, good old Dawn did the trick.

However, there was now a new problem, in that I was not going to soak anything made of steel in a water based solution, as I didn’t want it to rust, so what to do. In the end, I decided that while it had to be in water, I would do everything possible to limit the exposure, and to make sure the parts got completely dry as quickly as possible. I used an ultrasonic cleaner to help agitate the solution and get it into all of the nooks can crannies of the bearings. The strong solution of Dawn and water was very hot to help both the cleaning and the drying. As soon as each piece was clean and well rinsed, it was dried off with a hair dryer for a long time while spinning the bearings, until the metal was quite warm. And then I crossed my fingers, that I didn’t have any missed water lurking, just waiting to rust it up the next day.

Cleaned rear bearing after removing the cover.
New rear bearing cover made out of styrene.
Cleaned front spindle bearing.

I left the bearings for a number of days to see if there was any friction that would indicate some rusting, and there was none. They were then repacked with new grease and pressed back into the headstock casting. I was concerned about how best to do this, as using a hammer is not recommended. I settled on a threaded rod with tubes at each end to get the pressure on the correct part of each bearing.

Rear bearing pressed into place, before grease.
Pressing the spindle into the headstock using my homemade setup.
Note the two plastic tubes on the ends to apply pressue to the right places.

As I tightened the nuts on the rod, it slid into place so smoothly I was amazed. Slow, steady pressure was the way to go.

In place before grease.
Lots of fresh grease!

With it all back together, I was able to quickly process the rest of the plastic end caps, and they were ready for installation in the fascia.

The setup for facing and drilling the caps.
Finally all caught up, ready to install.

Maybe it will now last another 73 years?

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