Turning PVC

[RVC]

I have just acquired my first lathe with the intent of making whistles and flutes out of PVC. If someone could point me to a source of info on how one turns PVC I would appreciate it.

Thank you.

RVC

[highwood]

metal or wood lathe?

take it slow or the plastic will get hot, get soft and produce nasty fumes - cooling even with just air helps, water mist works better but creates a mess if you are set up well for it.

don't know of any particular online resources, I have seen some references on drills and tools to use for plastic - do a search I do not have any of them handy, standard metal working tools have worked for me

[RVC]

It's a metal lathe. Thanks for the info and insights.

RVC

[Dain]

What do you need lathe for, actually???
Eventually to make a conical-shaped whistles, but then you'll need solid plastic rod, not PVC pipe.
Anyhow, i had been working with plastic on industrial machines (programming industrial CNC lathes and graters) but it wasn't PVC.
I worked on PVC with modeling tool and it turns out that it heats very easily and acts as it's kinda layered (or laminar); meaning that it doesn't heat evenly, but the layer that has contact with the drill actually melt.

If you're working on a lathe, do it on low speed.
And stay out of the dust, it's not good.

[ahogrelius]

If you're working on a lathe, do it on low speed.
And stay out of the dust, it's not good.

Also, use cutting tools with sharp edges instead of the standard hard metal inserts that have edges that are way too blunt. With the inserts you will shear the material instead of cutting it...

Cheers,
Anders

[brewerpaul]

If you turn PVC, you won't really get dust-- you'll get ribbons of plastic. With acetal, I snatch that ribbon off the lathe tool and gather it up in my hands as it comes off. It's a pain in the butt and requires constant attention, but if you don't do that, the ribbon wraps around the turning plastic, bunches up and interferes with the turning.
If you sand PVC, you will get dust . Sand it with wet/dry sandpaper, used wet.

[Feadoggie]

If someone could point me to a source of info on how one turns PVC I would appreciate it.

Just as the others have said... Any tutorials or books on machining will give you a decent start. They should all talk about plastics along the line too. Use sharp tools. Mind your spindle speed, depth of cut and feed rates and you'll do fine. You will discover what works best for your set-up as you go. Let us know what turns up.

Feadoggie

[RVC]

What do you need lathe for, actually???

I want to try to make a whistle with a mouthpiece along the lines of the Water Weasel. From looking at the various pictures I've managed to find of this whistle it appears the outer piece of the mouthpiece is machined on the inside to about half the original wall thickness. The inner piece appears to be machined to fit snuggly in the outer piece. I couldn't figure any way to accomplish this except on a lathe.

---------------

To all others, thank you for the input. This will be an interesting learning curve.

RVC

[Feadoggie]

I want to try to make a whistle with a mouthpiece along the lines of the Water Weasel. From looking at the various pictures I've managed to find of this whistle it appears the outer piece of the mouthpiece is machined on the inside to about half the original wall thickness. The inner piece appears to be machined to fit snuggly in the outer piece. I couldn't figure any way to accomplish this except on a lathe.

That's the gist of it. The thickness of the outer mouthpiece collar determines the widway height. That can be varied depending on how you like the whistle to sound and behave. A lathe is the right tool to make that piece. That was what prompted me to buy my first lathe. There are a couple of ways to approach it. But basically you chuck up a piece of tubing and bore out the inner wall to achieve your desired diameter. The thinner the wall becomes the more interesting it can be to control your cuts. After a hundred or so whistles you'll get the hang of it.

Of course you can make a PVC whistle without using a lathe but since you have purchased one you might as well hop on the cafeteria tray and just start sliding down the slippery slope of whistle making.

Feadoggie

[Dain]

I want to try to make a whistle with a mouthpiece along the lines of the Water Weasel. From looking at the various pictures I've managed to find of this whistle it appears the outer piece of the mouthpiece is machined on the inside to about half the original wall thickness. The inner piece appears to be machined to fit snuggly in the outer piece. I couldn't figure any way to accomplish this except on a lathe.

Jesus Christ, just 2 minutes before reading this (again) i have been thinking of taking my Al tubing to a locksmith's workshop down the street, for the same treatment...

Yeah, thinning of the inner wall of the mouthpiece cover and thinning the outer wall of the mouthpiece part of the whistle body is the right stuff.

[brewerpaul]

Turning the inside as you describe is known as boring. You'll need a lathe tool called, no surprise, a boring bar.

[Feadoggie]

RVC, here's a visual example of a boring operation. I apologize to Misha Somerville for shamelessly borrowing this picture from the MK Whistles website.



You can see the tube stock held inside the lathe spindle and being worked on close to the chuck, probably a collet chuck. The boring bar is held in the toolpost and runs inside the tube stock shaving off material from the inside of the tube. Hope that helps.

Feadoggie

[Tommy]

There are some annoying fumes released when machining pvc. I do not know if they are poisonous but they make my nose stuffy, and irritate my eyes. I tried working under a celling fan to dissipate the fumes but it seemed to just recirculate them. There are some flute makers that have made a vacuum system with a collector hood just above the work. I did not want to go the expense of a good vacuum. I made a four sided box around my lathe covering some of the top and the two sides and bottom. Left the front open enough to use the machine. Put a small window fan in the back to draw air over the work collecting the fumes and disapating them outside. Also had to put a cheap AC filter on in between the fan and box to prevent curly Q's of PVC getting into the fan.

Using sharp tools has been mentioned. The cutting tool must be at the correct height also.
To high and it will not cut it will just rub. To low and it will gouge, chatter, and the pvc will try to climb up on the cutting tool.

[hoopy mike]

Would nylon be a better option? I used some machined nylon rod as a fipple block on a couple of PVC whistles. I'm not an expert though...

[RVC]

Thanks again for the info, guys, and for the really good picture. It's all appreciated.

RVC