Articulated arm and cutter position when hollowing.

[Ed Morgano]

I took a series of pictures today to show the position of my articulated arm and cutter when cutting a hollow form. These pictures show a 6" diameter x 3" tall hollow form with the cutter in several positions from entry to the bottom of the form. This also shows hollowing through a 1" hole. Hope this makes sense and helps others.

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[Ed Morgano]

Here are the rest of the pictures.

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[Jon McElwain]

Hey, now that's a great little tutorial! Thanks for putting that together. The only comment I would make is that I typically do the majority of my hollowing with a straight shaft tool, and only use the bent tools for the shoulder where the straight bar cannot reach. I suppose I do this because I keep the back side of my lathe open so I can stand there to hollow. If I was up against a wall, I would probably do a lot more of the hollowing with a bent tool like you have depicted.

Again, thanks for putting that together!

[Jon McElwain]

It would be interesting to see the same depictions with your laser turned on...

[Bill Bolen]

Clever and well done tutorial Ed. I would have to make 3 bit changes to get the cuts you are showing. Guess I better look at making an additional swan neck using yours as an example. Thanks for the timely post too as I just finished rough shaping a piece with a similar form.

[Russell Neyman]

A wooden articulated arm... who would have thought! Has anyone done this before?

[John Keeton]

A wooden articulated arm... who would have thought! Has anyone done this before?On a wooden lathe - that is the neatest part!! Ed is quite the craftsman.

Ed, this is a great tutorial, of sorts, and Jon's comment on the laser is a good one. Positioning the laser for each series of cuts is critical to success.

You should post a close up pic of the manner in which you have attached the cutter to the bar. The shape of your bar seems much more adaptable than my swan neck - which I rarely use.

[Michelle Rich]

wow, what impresses me is the wooden art. arm! you da clever dude!

[Dan Forman]

I think I might do a similar setup to get to the bottom of my tendency to cut through the wall of a form about an inch to an inch and a half from the opening. I really can't visualize where the cutter is once it's out of sight in the form. I have thought about drilling several "vision holes" in a practice form so that I can get a better of what is happening, but maybe this will serve the same function. Love the way you are holding the graph paper with the chuck to assure proper orientation.

Dan

[Ed Morgano]

Ok, here are some more pictures with the laser on. I position the laser right at the tip of the cutter and then cut to the wall thickness that i'm shooting for using the laser to sight the wall thickness rather than moving the laser off the cutter and using it on the edge of the piece.

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I'm using a 1/2" bent bar. The cutter is a used 1/4" carbide router bit sharpened to the shape shown. The 1/2" bar is fitted to a 3/4" main bar about 12 - 13" long. Actually, I have several cutter bars of different sizes but this it the one that I use for most everything.

[Ed Morgano]

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Here are some more pictures of the arm. I've attached the 3/4" metal arm to the wood using two 1/4-20 setscrews that are drilled and tapped directly into the oak arm. Wood magazine did a thing on drilling and tapping wood. I've done it before but not for structural type things. Anyway, the screws hold surprisingly well.