ARTICLES & REVIEWS
Hollow Ornaments
by
Brad Vietje
Most people who turn hollow ornaments turn a batch of globes with a standard size hole, then a batch of spindles, or icicles, then glue the two together off the lathe. The results are usually beautiful, but I wanted an ornament that ran true with tight glue joints so I could cut through the join to create a smooth flow from globe to spindle, (and I had not seen a Robert Rosand or Dick Sing ornament when I came up with this method).
This is a somewhat slower method of turning hollow ornaments, to allow you to cut through the glue joint for design reasons. Directions given for a two-piece ornament, with the three-piece option at the end. For the two-piece ornament, the finial is turned from the chuck end of the globe, so be sure to leave about 1½" or so extra, depending on how adventurous you are turning very close to the spinning chuck jaws.
Start with any scrap of attractive wood, from about 1½" to 3" in diameter. Turn between centers to establish a foot for your chucking method (SuperNova with 35mm tenon jaws shown).
- Turn the globe to desired shape, leaving about a 1" diameter stem holding globe, and a flat face surrounding the drilled hole. Then drill a 3/8" hole to desired depth (all the way through for three-piece ornament; to opposite side of desired hollow space if a two-piece ornament).
- Hollow globe to desired thickness with small hollowing tools, or small bent scrapers made from Allen wrenches, etc. I usually hollow to 1/8" to 1/16". Enlarge hole if necessary to make hollowing easier. Remove shavings from inside often so they don't clog the opening, and grab the tool.
- True up opening and flat face for a good glue join, making sure there is a clean, square step between the face and the drilled cylinder. See photo #1.
- Prepare a contrasting wood dowel to serve as the spindle. Size a tenon on one end to fit snugly into the hole drilled in your ornament. I turn these between centers, usually tapering them from the globe end to the tip so the turned features get smaller towards the tip, which I find aesthetically pleasing. Next, size the tenon, then bevel the far end, which will be the tip of the spindle, to rest in the V-cup of a live center, before parting off the other end to leave the carefully sized tenon at the end of the dowel.
With the globe re-chucked and running true, glue spindle dowel into ornament hole, using the tailstock to clamp the two, and to keep the dowel in true alignment with the globe.
Once glue has cured, with the spindle now held between the globe and the tailstock, turn the spindle details desired. Despite your best efforts, the whole concoction may not run exactly true, so true up the spindle first. Add as much or as little detail as you wish, in general going from larger to smaller details along the length of the spindle, and leaving a small bridge to the tailstock.
- Sand to at least 320 grit while there is still good support from both ends. See below for three-piece option.
- Reduce the stem diameter at the chuck end, and turn a small finial from which the ornament will hang. You can either leave a large enough finial to accept a small screw eye, or turn a fine finial, which you can drill through to accept a fine wire hanger. Do not part off yet, but leave a small support tenon to allow finishing and polishing.
- Complete sanding, apply desired finish, and polish as you wish between centers. Once you are satisfied with the finish, carefully part off tip of spindle at tailstock end, while supporting the ornament with one hand. The entire ornament will now be suspended from the small tenon left at the chuck end, so you will have to continue to provide gentle, steady support.
Using a small detail gouge or skew, part off the ornament at the chuck end (top), and admire your work ! Photo is a composite of finished ornaments.
Three-Piece Option:
To make a three-piece ornament with separate pieces for finial, globe, and spindle, make the following modifications:
- In step 2, above, drill all the way through the globe blank. Re-chuck between centers, driving the blank between the two ends of the drilled hole, to keep things centered in case there was any wandering of the drill bit. True up the foot for the chuck jaws, so you will be turning exactly on-axis with the drilled hole. return blank to the chuck jaws before proceeding with hollowing.
- Ignore Steps 9 through 11, above.
- Using sharp parting tool, create a small step at the chuck end of the globe, leaving a thin hollow tenon onto which the finial will be glued. For a 3/8" hole, I usually leave a tenon about 3/16" long, and about ½" in diameter.
- Complete sanding, and polishing of the ornament.
- Now carefully part off the ornament, leaving the small tenon you just created standing out of the end of the globe. backing up a bit, as an alternative to creating a male tenon attached to the globe, you could part the globe off, and make a finial with a small tenon to fit the hole in the top of the globe.
- Chuck up a small piece of wood to create the desired finial, either with a small female hollow sized to fit the globe tenon described in D & E, above, or a short male tenon sized to fit the hole in the top of the globe. The top finial can be glued onto/into the globe off-lathe, or, if your design calls for another cut-through glue joins, see the trick, below.
Neat little trick:
I had to repair an ornament that was worth the extra effort, because it was made from a piece of wood with sentimental value, as well as about $15.00 worth of African blackwood for the finial and spindle. I discovered that a very small rubber grommet from the hardware store would cradle the finished tip of the spindle, and mount into the "V" cup on my live center. this can be used to add smaller details, including the seamless join on the finial (as in F, above), or to repair a damaged ornament. There are also white rubber stoppers with small holes that would work for light-colored woods.
Technical Notes:
If the globe is hollowed leaving a short cylinder where the original hole was drilled (even if enlarged), this can act as the primary glue surface, allowing you to cut through the perpendicular surface, between the spindle and the flat face of the globe. These must be carefully trued up and as flat as possible, or the glue line will not look good.
For stepped transitions between pieces of wood, the pieces should be squared and flat, but the margin of error is relaxed a bit.
If you wish to make these smooth, step-less transitions between globe and spindle or finial, be sure the drilled hole and/or fitted tenon are exactly centered, or the resulting glue line will look crooked—this is, after all, the original reason for all this fussing!
To drill the finial for a wire hanger, decide which face of the ornament should be presented forward (if any features of the wood should be more prominently displayed), and make a tiny divot with the tip of a sharp skew at 90° to this. In other words, with the desired face forward, make a little indent to the right or left side of the finial. This is to give the drill bit a purchase, and keep it from wandering. Carefully drill a 1/16", or slightly smaller hole through the finial, from one side to the other, being careful to drill through the center, and not at an angle. I hold the drill in my right hand, and the ornament in my left, and have never had a single problem. I use a spool of fine brass wire from the hardware or craft store to fashion S-hook hangers, bending the wire by hand around the closed tips of my needle-nosed pliers, sizing as needed for the hole and the tree branch, or object from which it will hang. You can also create your own hook eyes by doubling over a 1" piece of wire, and twisting the ends, and gluing these into a 1/16" hole drilled into the end of the finial.
. . .
Brad Vietje
©
2004 by
Brad Vietje
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