Old School meets New School (or how to oil your lathe)

wrmiller

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Found these (there's another one intended for the front bearing) online and thought they looked cool.

The oilers have this goofy 1/8"x27 NTP(?) thread on them. Fortunately, my tap/die set has these, but why do they have a tapered thread? Probably a good reason somewhere, but it's a pain to tap and get the depth/dia. right. And I'm probably doing it wrong, but I got the first one done.

One done, one to go.

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Those are 1/8 npt threads and are part of a series of pipe thread sizes used in piping of all kinds, especially in the U.S. Npt stands for National Pipe Thread and are nominal not literal sizes. A quick net search should give you ample information on the various kinds of pipe threads used throughout the world including npt. The oiler is probably a Lunkenheimer brand or equivalent replica. The pipe threads are tapered to provide sealing pressure. A suitable pipe "dope" sealant, or pipe tape is recommended. Some precautions when using Teflon tape on these type threads are, 1) stay back at least 2 threads from the ends of these threads to avoid system contamination, especially in hydraulic systems, and 2) be careful when tightening tapered threads in cast iron including malleable. If you need to combine a couple of these threads to adapt a small thread to a larger port, install the small threads in order from small to large. This will lessen the chance of damaging castings if you need to do this. They are also produced as nptf which are often called dry seal. The designation means National Pipe thread Fuel if I remember correctly. (I'm getting a bit "long in the tooth")
 
You can get those in different thread sizes...


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Cool.
I hope that you cleared ALL the scarf after threading the holes! Other wise the bearings may look like this after a while.
Pierre

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Thanks guys.

And I only threaded into the adapter. The adapter is a push fit into the headstock. This is definitely a low pressure system. :lmao:

Now when I get ready to use the lathe, I just open the oilers for a few seconds and go.

Bill
 
Second one turned out better than the first, so I'll remake the first. Happens when you're designing/turning on the fly? :LOL:

Bill

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... in the U.S. Npt stands for National Pipe Thread ...

Uncle Harry

Until recently, I too thought that NPT stood for National Pipe Thread, but I have subsequently learned that NPT stands for National Pipe TAPER. There is also a series of NPS (National Pipe Straight) threads.

Len
 
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