How do you turn the inside of a cone??

[scmhogg]

I would like to make one of these for my doctor. How do I turn the cone shape inside.



Steve

[BigguyZ]

I'm sure there are specialty tools for such work. I'd imagine the first step would be to drill through the center, and then remove the inside slowly- much like any bowl or hollow vessel. The only difference I see is the shape of the interior of the piece.

But what I'd really like to know is, what the heck is that?

[scmhogg]

I'm sure there are specialty tools for such work. I'd imagine the first step would be to drill through the center, and then remove the inside slowly- much like any bowl or hollow vessel. The only difference I see is the shape of the interior of the piece.

But what I'd really like to know is, what the heck is that?

It's an antique stethoscope.

Steve

[woodturner]

I would like to make one of these for my doctor. How do I turn the cone shape inside.

I would turn the approximate shape with a small gouge, then use a small scraper in shear cutting mode to smooth the sides. How "pointy" does the inside have to be? Getting a sharp point will be tough, but a small gouge would work it to a slightly radiused end.

[leehljp]

For me in similar long turnings, I used a 1/2" drill bit and drilled to the approximate depth and then began turning. To me, that bit of drilled hollow space makes it easier and faster to turn objects to hollow, and the depth of the drill lets me know my progress.

[crokett]

for that shape you would either need a side scraper or a carbide-tipped tool such as an EWT or a shop knock-off. A bent hollower won't fit. Drilling out much of the waste is a good suggestion. The carbide tool is a better bet - you will be working a good distance off the tool rest.

[cabinetman]

That's a beautiful piece. Maybe you could do like Hank suggested with hogging out with a drill, and then maybe a hollower might work. I will say this...if my cardiologist pulls out one like that for my exam...I'd be real worried.

.

[Stytooner]

Looks like Shrek ears to me.




If I did something similar on my cnc lathe, I'd use boring bars. Probably a larger size to start with after drilling initially of course.
Then the smallest long bar I had to complete. I think it would require a special tool if you wanted the funnel taper all the way to the tiny hole these things must have had.

[leehljp]

My curiosity is piqued! Think I will try to make one!

[phrog]

...if my cardiologist pulls out one like that for my exam...I'd be real worried.

.

If your gastroenterologist pulls one out, get more worried.

[jdon]

If your gastroenterologist pulls one out, get more worried

Or urologist!!

[chopnhack]

for that shape you would either need a side scraper or a carbide-tipped tool such as an EWT or a shop knock-off. A bent hollower won't fit. Drilling out much of the waste is a good suggestion. The carbide tool is a better bet - you will be working a good distance off the tool rest.

Shall we say welcome back David?

[cabinetman]

Or urologist!!

Or the proctologist...yeeoow!!


.

[cabinetman]

shall we say welcome back david? :d

+1. Welcome back.

.

[scmhogg]

I think I am going to try, as Hank suggested, drilling out most of the unwanted material. I'm going to try using forstner bits and step down sizes. Then I can scrape out the ridges.

Steve