Maybe not this particular job but another way to "look at it" would be 2 or 3 short pieces and solvent weld them together in a fixture. :-)
...lewie...
Thought: (hey, I have them on occasion)..
since this thing is coming down to about zero wall thickness. (.125 to .25"). Would it
be easier to just get a sheet of maybe 3/16, and roll it?
I can't imagine boring that thing out to be anything but a giant cluster F*..
You'd need to hold it 360 degrees, and pretty much full length. FCiron has a good idea,
I think that would work with the least amount of fuss, and the highest chance of success.
As for asking about the boring bar. I wouldn't waste a nickel on it. Just for fun many years
ago, I made a cutting tool out of some 2024 aluminum just to see if it worked, it did. A simple
piece of HSS clamped or brazed onto just about any piece of scrap you have kicking around the shop
would work fantastic.
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Thin wall plastic SUCKS!!!! I got suckered into modifying some teflon rings the other day.
They weren't 14" and they weren't a foot long, but they still sucked, taking them down to a
.040 wall thickness with .008" tolerance on the ID. Hold it in my hand for 45 seconds and the
no-go would go. Put it in the frig for 3 minutes and the go wouldn't go.
PVC is at least decent to deal with. Cuts easy, and its moderately rigid. Not as nice
as Delrin to machine, but its not too far off.