I was wanting to use a vacuum chuck on my lathe so first thing I needed was a way to get vacuum to the spindle.
Lucky for me, or not so lucky, my spindle has a hole cross drilled into it! This made my project a bit more involved, but still successful. I used a threaded lamp rod to supply vacuum through the spindle along with a couple of ball bearings, pipe fittings, and two spindle adapters I turned.
All the meat and potatoes is in my post, Make a Vacuum Adapter For Your Lathe. It’s a quick read and you could probably just look through the pictures to figure it out.
BTW, learn from my mistake and don’t use push to connect fittings… I was totally bummed about that :(
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