A box full of neutrals?

Have you seen a man skillful at his work? He will stand before kings; he will not stand before common men

It’s always quite exciting when you begin to dismantle something you don’t understand at all! The exciting part is the anticipation of understanding once you’ve finished.

We’ll see if that’s true!

This lathe has a Gearbox. I know that it controls the speed of rotation of The Lead Screw, which controls the movement of The Saddle along The Slide. Something to do with cutting screw threads. Hopefully I’ll learn what all that means when I go on the Beginners Course at Axminster Power Tools in September. For the moment though, I’m just going to dismantle, clean, inspect and assemble.

So here’s the back of the Gearbox…

20140611-102037-37237130.jpg
Looks like more of that pesky wood dust. This is a view of the inside having taken off the top…

20140611-102313-37393370.jpg
The largest cylinder is The Guide Bar. It has a Selector Lever. You pull on the black handle to move the lever left and right into the detents along the front body. It was impossible to photo, but the underside of the Guide Bar is cut out to allow a Tumbler Gear to move along an Input Shaft with the Selector Lever. This gear is driven by the Input Shaft inside the Guide Bar and engages with the other gears to transmit the drive. You can see the Input Shaft end poking out of the left end of the Guide Bar.

This a picture of the diagrams from the manual. I copied them, enlarged them, printed them and stuck them to a board so that I could have them upright next to my bench. The parts described above are 169, 170, 179 and 183. Turned out to be really useful…

20140611-112003-40803011.jpg
I could get the Drive Shaft out…

20140611-103706-38226864.jpg
…but the gear was impossible. The only access to it’s retaining stud was from underneath the body through the sump hole. I thought, even if I can get it out, what if I can’t get it back in? So I left it. At least I could slide the Guide Bar left and right to gain easier access to the sump.

Looking deeper in, there was quite a lot of oil in the sump when I took it off the bed, but I poured that away because it looked black. There’s still a lot of oily gunge left…

20140611-102553-37553198.jpg
In the above picture I’ve pulled the Guide Bar to the right out of the way. On the left, you can see the inner sides of the large hole in the body into which the Guide Bar goes.

Dismantling was limited from then on. For example there was a couple of keys which I couldn’t get out. Here’s one on the upper shaft of gears…

20140611-104655-38815019.jpg
It wouldn’t budge easily, and as I tried different tools to dislodge it, I was leaving marks on it, so I decided to leave it in, and clean the two gear trains in situ. I did carefully turn each shaft to inspect for cracks and nicks. They were all in good condition. I found I could get the Selector Lever handle off by unscrewing these two grub screws…

20140611-105802-39482749.jpg
…then I dismantled the handle itself and cleaned the parts in GUNK…

20140611-105906-39546156.jpg
The cleaning process, as before, involves coating in GREEN GUNK, leaving for a while, then scrubbing with brushes and rinsing off. Obviously applying water to bare metal might induce rust, but previous experience proved that if I dry immediately with cloths, paper and a hot air gun, this doesn’t happen, apart from the odd spot of surface flash rust.

So I gave all the parts a good soak in GUNK, scrubbed them individually with an old tooth brush and a little wire brush, then rinsed them all thoroughly in running water. I spent quite a while with the hot air gun making sure all moisture was driven away from the gears.

Here’s the clean Gear Box body…

20140611-110907-40147188.jpg
The two slots with holes at one end left and right on the top edge are oil galleries. They are fed through nipples (fnar fnar) on the cover and are to lubricate the gear shafts. It was important, then, to make sure the holes were 1, clear of gunge and b, bone dry. The sump drain hole can be seen at the bottom of the sump. A good place for it, I believe.

Here’s a picture of all the parts, cleaned…

20140611-111719-40639573.jpg
What of the oil? The correct oils to use and lubrication schedule is in the manual. The oil was available from Lathe Supplies, so I ordered some and it’s already arrived. I thought about oiling all the parts, but decided that I would clean all the remaining parts in the drive system first, then oil everything as I reassembled.

So do I understand it? Yes.

Next, the Gear Box Top Cover (part 260) and the rest of the drive system…

PS

When I checked this entry on the website, the diagrams didn’t enlarge clearly, so I’ve added two extra pictures..

20140612-080355-29035329.jpg

20140612-080354-29034937.jpg

Advertisements