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Home Articles Page David@DavidReedSmith.com This article was published in the Winter 2011 (#28) edition of Woodturning Design. If you would like to be notified when I post a new article, send me an email. I'll only use the list for that purpose, and I'll mail blind cc so your address won't be any the worse for spam. If you have comments, questions, or suggestions I'd enjoy hearing from you. Just send me an email. My address is David@DavidReedSmith.com. If it's a suggestion I'd be happy to post it along with this article. Let me know if you would like your email address posted as part of the attribution, or limited to only name, or only first name, etc. Snowflake Ornament9 page version in pdf format Miter sled Miter sled as pdf IntroductionI have long thought that I preferred to turn utilitarian objects. But I’ve also done a lot of Christmas Ornaments, whose sole and rather tenuous claim to utility is decoration. I’m not really all that hung up on consistency but it does puzzle me now and again. A month or so ago I was reading Shop Craft as Soulcraft where Matthew B Crawford explained the advantage of a job with physically measurable results, such as carpentry or motorcycle repair, is that one is freed from the necessity for “chattering interpretations”. Likewise Christmas Ornaments are usually recognizable as such (except, as my wife unkindly said, when they look more like coasters). They either look good on the tree or they don’t, and are light enough the tree can support them or not. A neat explanation of my puzzle, and the rest of the book was interesting as well. Although not a book to read if you don’t like to look up words. Enough of this diversion (perhaps I think the picture alone will hook you into reading the article and I don’t need a good opening?) and on to the Snowflake Ornament. I think it’s visually attractive, has a good “how’d he do that” component, and has a lot of negative space so it can be made of most any wood without being too heavy. It’s sort of like an inside-out ornament that’s only opened up instead of turned completely inside out. Briefly, the ornament is started by ripping an equilaterally triangular stick on the table saw. The stick is cut into 6 segments (one for each arm of a snowflake) and the segments are mitered on one end at 30 degrees. The segments are then temporarily fastened together into a hexangonal cross-sectioned spindle with blue masking tape and wood glue. A flat drive plate with a removable center pin is made, and the hexagonal spindle is fastened to it with blue masking tape and hot melt glue. A pattern is turned into the spindle using tailstock support as long as possible. The hexagonal spindle is split apart and glued into a snowflake. The snowflake is remounted on the drive plate to turn the center of the back and any irregularities in the miter joint are covered with a small additional decoration to complete the ornament Triangle SegmentsRippingBecause the snowflake design has a lot of negative space you can use any wood you like without worrying overly about having too heavy an ornament. However because the ornament suggests a snowflake, light colored woods are appropriate. Maple is a good choice. Knot free (or cut around them) pine is also okay if you want something less expensive. ¾” thickness yields a nice result. I weighed a typical glass ornament—it had a Norman Rockwell illustration—it was 20 grams. Pine snowflakes were in the range of 11 to 15 grams, and maple snowflakes were in the range of 20 to 25 grams. The method of ripping I’ll describe is vulnerable to small differences in the width of strips, so begin by cross-cutting a board to a length long enough to yield six 2-1/2” long pieces out of the same strip, about 16-1/2” long. Then set your table saw blade to 60 degrees as measured from the table (or 30 degrees as measured from perpendicular, the way most table saw scales read). It will be most accurate if you use a known 60 degree angled triangle. Raise your blade to maximum height and match the blade to the angle as in Fig01. The method of gluing the segments into a hexagonal cross sectioned spindle with tape allows for some error, but set the blade as accurately as you can. Then set the board you’ll use on the table and reduce the blade height so that it’s a tooth or so above the board as in Fig02. Fig1 Setting the table saw blade to 60 degrees.
Fig2 Setting blade height for ripping triangles. Set your rip fence so that the blade removes the minimum to get a full 60 degree angle side. Mark the location of your rip fence with a strip of masking tape on the outboard side of the rail. Then rip the edge of the board as in Fig03. Flip the board lengthwise and reset the rip fence as in Fig04 so that you’ll get the largest triangle possible. Then rip the board as in Fig05. Use a pencil to make a line down the original surface of the board (the unripped surface) so all the segments can be oriented the same in case your angle is off slightly. Before moving the fence, use a piece of cardboard or stiff paper to measure the distance between the fence now and the tape that indicated where it was for the first rip as in Fig06. Now move the tape against the edge of the fence mount, and use the cardboard to move the fence the same amount. You can use the cardboard gauge after the first rip for any board of the same thickness. Continue flipping the board and moving the fence and ripping until you feel the board is too narrow to rip safely using a push stick. To salvage additional use out of valuable narrow board you can glue a waste board onto one edge as in Fig07 (to make it easier to reuse the waste board I put blue masking tape on the edge of both boards, sanded the tape lightly, and glued the boards together with wood glue (not hot-melt this time, as that would yield a glue line of uneven thickness))
Fig3 Making the first rip to put a 60 degree edge on the board.
Fig4 Setting the rip fence for the second rip.
Fig5 After the second rip.
Fig6 Recording the rip fence interval for subsequent rips.
Fig7 Using a scrap board as a width extension to safely rip narrow stock. Crosscut & MiterIf you’re only planning to make a few ornaments, or to try the technique out, you can use a sled and miter gauge to cross-cut and miter the segments. Set the stop on your sled fence to 2-1/2” and cross cut a triangular strip into six 2-1/2” segments as in Fig08. Keep the segments for any given strip together as there may be slight differences in size—rubber bands work well for this. Cut as many sets as you want to work on at this point. Fig8 Cross-cutting segments with a table saw sled. Note the rubber bands keeping the segments from a previous triangular stick separate. To cut the miters at 30 degrees you’ll need to put an extension on your miter gauge. A plain pine board will do. Make it long enough to extend past the blade. Set the miter gauge to 30 degrees and pass the temporary fence through the blade. This will create a kerf that will help you set a stop block for the segments. Bring the miter gauge back so that the kerf is over the table and mark with a pencil on your table. Mark the middle of an end of a segment and place it on the temporary miter gauge fence. Slide the segment until the marked middle matches up with the kerf line. Fasten a stop block to set the segments repeatedly at this point. I used a screw. A clamp would be okay. Then cut all of the segments in this batch at this setting. For consistency keep the marked (non-ripped original surface) down. Again, keep segments from different strips segregated. Fig09 shows cutting the first miter. My fingers felt uncomfortably close to the blade, and I had to press hard on the top edge of the segment to avoid creep. In hindsight I should have tilted the miter the other way. Fig9 Cutting the first miter with miter gauge and extension. Now set the miter gauge for the opposite miter using the same procedure. Fig10 shows cutting the second miter. I switched to the other miter gauge slot. Again it would have been more comfortable had I tilted the miter gauge the other way. Fig10 Cutting the second miter with miter gauge and extension. Crosscut & Miter with JigMore detailed plans for a second generation jig. A more comfortable way to cut the miters is to make a jig—in this case a dedicated sled as in Fig11 if you want to do this option. Cut two rectangles of ½” plywood 7” by x12”, or about 2 inches wider than the miter gauge slot separation. Also cut two UHMW 3/8” x ¾” strips 7” long. Set one of the plywood rectangles on the table saw straddling the miter gauge slots with an edge aligned with the front edge of the table. Mark where the miter gauge slots go under the plywood. Remove the plywood from the table saw and drill and countersink for two screws for each slot. Fig11 Miter jig to make miters more comfortable.
Place the UHMW strips in the miter gauge slots with one end of each strip even with the front of the table saw table. Place the plywood straddling the miter gauge slots with an edge even with the front edge of the table. Use a couple of clamps to hold it that way and then attach the plywood to the strips with wood screws. Be sure to select screws that won’t go all the way through the strips and scrape on the table saw slots. Drill and countersink four holes, one near each corner (except about 2” down on the top left corner) in the other plywood rectangle. Line up the rectangles and fasten them together with wood screws. Turn on the saw and cut about half way through the jig. Measure ¾” down from the top of the jig and mark across the kerf. Draw a 30 degree line from where the mark intersects the kerf on each side. Draw another pair of lines parallel to these lines 1” higher. Select a segment and mark the middle of one end. Place it on the lower 30 degree line so that the middle mark is on the kerf, then trace the opposite end. Repeat on the other side. Measure and mark 2-1/2” from the right side of the kerf to the right at the top of the plywood. Draw a ¾” line perpendicular to the top edge at the mark. Draw a line parallel to the top edge ¾” below the edge from the left side to the perpendicular line. Remove the top plywood rectangle. Cut on the lines and then replace the top. Do a test run with a segment to check your work, and if all is well refasten the top piece with glue and screws. To use the miter jig first cut a piece to 2-1/2” length using the rebate on the top as in Fig12. Then cut the miters as in Fig13 and Fig14, keeping the marked side of the segments facing down. My fingers felt quite a bit safer doing it this way.
Fig12 Cross-cutting segments with miter jig.
Fig13 Cutting the first miter with miter jig.
Fig14 Cutting the second miter with miter jig. Turning Hexagonal SpindleAssemble Hexagonal SpindleThe first step in assembling the six mitered segments is to apply blue (or other extended release) masking tape to the mating surfaces. The tape will allow you to split apart the hexagonal spindle after sanding and clean up with only a little mineral spirits. The tape should be applied to the ripped surfaces, not the marked surface. The miters do not have to be taped. The tape holds better if the coating on the top is sanded. You may find it faster to transfer the tape to a clean flat surface and sand lightly first. Once the tape is applied and sanded gather some wood glue (regular Titebond allegedly grabs quicker than the later versions) and a couple of strong rubber bands to use as clamps as in Fig15.
Fig15 The set-up for assembling the hexagonal spindle. Start assembling the hexagonal spindle by applying some glue to a segment and rubbing it against another to spread the glue as in Fig16. Continue until all six segments have been added and then wind the rubber bands around the hexagonal spindle. Set the spindle on a flat surface with the mitered ends pointing down and push on each segment so that the points are all aligned. Have a look at each end of the spindle and try to align the segments so all of the inner angles meet at one point. Then set the hexagonal spindle aside until the glue cures as in Fig17. After the glue cures remove the rubber bands. Trim both ends using the table saw sled as in Fig18. Remove only a little bit from the end with miters resulting in a flat about 1/16” wide as in Fig19. The flat on the miter end allows us to mount the spindle for turning, as well keeping the points from interfering with the fit in the final assembly. Trimming the other ends keeps the tailstock from pushing the spindle out of alignment when mounting.
Fig16 After applying glue to one taped segment face.
Fig17 The hexagonal spindle clamped together with rubber bands while the glue cures.
Fig18 Trimming the ends of the hexagonal spindle.
Fig19 The miter end of the hexagonal spindle after trimming. The flats make it easier to mount the spindle for turning. Removable
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