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Jim discussed grain on this chain sawn blank.

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Jim begins to shape the hollow form.
JIM NEFF HOLLOW FORMS FEBRUARY 2003

By Lee Buck

Jim Neff demonstrated how he turns hollow forms.  Jim begins with a blank which has been chainsawn as round as possible.  The blank can be mounted either spindle or bowl orientation.  The piece Jim used for the demonstration was mounted in spindle orientation.

Jim mounts the blank between centers, turns it round, and turns tenons on each end to fit a scroll chuck.  He mounts the blank in the chuck and rough turns the outside shape with a bowl gouge.  The bottom section of the form is left heavy to provide more support for hollowing.  Jim uses a Milwaukee bit in a Jacobs chuck in the tailstock to bore a hole to the desired depth of the interior of the form.  The bit must be retracted frequently to clear the chips.  

Jim prefers a Stewart tool for hollowing but also uses homemade Ellsworth style tools when hollowing through a hole too small for the Stewart tool.  The hollowing is done from the top of the form.  A cut is established immediately inside the rim at the desired wall thickness.  Sweeping cuts are made from the bored hole to the cut established inside the rim.  The wall thickness is established again for the next section and the sweeping cut made from the bored center. Each small section is brought to final thickness before moving on.  Jim uses fine cuts to remove any ridges between finished sections.

Jim uses a figure eight caliper to check wall thickness as he goes.  He aims for a wall thickness of 3/16" so the piece can dry evenly.  Sound is also a good indicator of thickness.  Both the sound of the tool against the wood and the sound made by tapping the piece indicate thickness and evenness.  


Jim reverses the form onto a jam chuck, which is a cone shaped form held in the scroll chuck, and turns the bottom.

After sanding Jim finishes the piece with lacquer.  Jim uses lacquer because it is fast and can be applied as a satin finish or a gloss finish.    


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Final cuts are made to shape the form.  At this point Jim leaves the bottom a little thicker than the finshed product. This will reduce vibration whil hollowing.


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The blank is ready to be drilled.
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Jim likes to use Milwakee drill bits to start the hollowing process.  This can also be done with a spindle gouge, however, a drill bit can be faster and more accurate.

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You need to back the drill out every inch or so to prevent the drill from getting bound up in the wood shavings it produces.

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Jim's tools of choice for hollowing are the Stewardt Tools.

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These home made tools are used for smaller hollow forms.
When hollowing, always make sure the tool rest is on the straight part of the tool shaft.  If the curved part is resting on the the tool rest the tool will want to twist in your hand.

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Deeper into the form.  Jim can't stop smiling.

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Measuring thickness.  Jime gets most of his hollow forms to 3/16" thickness.  Going thin help to prevent a green piece of wood from cracking as it dries.

Jim uses the straight tool to clean up the bottom. One advantage to the straight tool is that you can put the tool rest close the the form.

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Jim shapes the bottom to the finshed shape after the hollowing is complete.

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The form is reversed chucked using a cone made from a scrap piece of wood.

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The tennon is turned away and the form is complete.

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