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Home Articles Page David@DavidReedSmith.com
This article was published in the Summer 2009 edition (Issue #22) 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.
Beading ToolIntroductionSmall and especially very small beads are hard to shape precisely. Using a pre-shaped scraper can solve that problem but introduces the problem of poor surface left by the tool. The surface can be improved dramatically by making the pre-shaped tool a shear scraper. Years ago, in 1999 I published an article on making a shear scraping beading tool by grinding HSS drill blanks. The trouble with that technique is grinding the shape freehand, so in the years since I’ve tried other ways. The majority of turning tools are made of High Speed Steel these days, and the difference in edge holding ability is particularly dramatic with scraping tools. But ordinary Oil Hardening Steel has one really big advantage for home tool making, and that is that it can be easily hardened and tempered—and before it’s hardened it is much easier to shape. The tool is made by using a drill to make a semi-circular groove on the bottom of the tool. This pretty much means that you can make any size beading tool that you have a drill bit for. There are limits, of course. As shear scrapers tend to require more pressure to work, and that increases with the contact area, the upper limit on practical size is about ¼”. I’ve made beading tools as small as 1/16”. Briefly, tool steel is cut to length and a rectangle cut out to form a tang. The offcut is clamped next to the bottom nose of the tool and a hole is drilled centered inbetween the tool and off-cut. This forms a precise semi-circular groove. A 45 degree bevel is sawn and ground and some detail shaping is done. Then the tool is hardened by heating and quenching in oil, and tempered in a home oven. Simple (bevel only) sharpening with both a V-block/grinder and a Tormek is shown. Then refined sharpening of the points is shown with a modified handle and either with a V-block and jig or with a Tormek. Shaping the ToolTangBegin by selecting an appropriate thickness of tool steel for the size beading tool you want to make. The steel should be in the neighborhood of 1/16” wider than the bead, and the width should be in reasonable proportion to the thickness. The pictures will follow making an easier to photograph 3/16” bead, so ¼” x 1” steel will be used. Mark off a 4-1/2” length of steel as in Fig01. Then cut the steel to length either with a hacksaw as in Fig02 or the power tool of your choice in Fig03.
Fig01
Laying out where to cut the Beading Tool Blank from a
piece of Oil Hardening Steel.
Fig02 Cutting the
blank to length with a hacksaw.
Fig03 Cutting the
blank to length with a reciprocating saw.
Layout the tang. It should be 1-1/2” long and half the width of the steel (1/2” for 1” wide steel) as in Fig04. With the tool of your choice first make the short cut halfway across the tool as in Fig05, and then the lengthwise cut as in Fig06. Fig04 Laying out the cutting lines for the tang.
Fig05 After the first tang cut, halfway across the width.
Fig06 After the
second tang cut, along the width.
Even though the tang will be tapered eventually, make the cut straight at this
point.
GrooveYou can prepare the tool for drilling by clamping the tang off-cut next to the bottom nose of the tool in a vise and using a C-clamp to keep the pieces together. Center punch halfway across the thickness at the intersection of the two pieces as in Fig07. With the two pieces still clamped together, clamp the tool in a vise on your drill press checking with a small square to make sure it’s perpendicular to the table as in Fig08. Fig07 After
center-punching the beading tool for shaping the groove with a drill bit.
The tang cut-off is clamped to the bottom of the beading tool nose, and
then both pieces are clamped in a vise.
The dimple should be on the center line of the tool at the intersection
of the two pieces.
Fig08 The tool and tang offcut, still clamped, have been transferred to a drill press vise and checked with a square to make sure they’re perpendicular to the drill press table. Insert the size drill bit that matches the bead size you want into your drill press as in Fig09 and begin to drill. Make sure the drill doesn’t deflect when it hits the center punched dimple or the hole may not be straight. Stop after just starting the hole to make sure it’s centered properly. If it’s not, you can probably recover by using a combined drill and countersink, which is rigid enough not to deflect. In fact you could skip the center punch step and just start the hole with the combined drill and countersink as in Fig10 and then drill with the drill without moving the set-up as in Fig11. The semi-circular groove that results from the drill is shown in Fig12.
Fig09 Set up to drill
on the drill press
Fig10 A combined
drill and countersink is rigid enough to start without a centerpunch, and with
care can even correct for an misplaced punch.
Fig11 After drilling.
Fig12 The resulting semi-circular groove after drilling and then removing the scrap piece BevelLayout a 45 degree line that intersects the lower corner of the tool (where the groove is). The next step is to saw a 45 degree bevel at the nose of the tool. This cut is a lot easier to do if you file a starting notch as in Fig13 so that the saw blade doesn’t skid about. After you’ve filed a notch with a triangular file (it doesn’t have to be as big as the one I used, that was just the one on top) saw the bevel with hand or powered saw. The result is shown in Fig14. Saw the tang to a slight taper to make it easier to mount in a handle.
Fig13 After filing a
notch where the 45 degree saw cut starts.
This keeps the saw blade from skidding about.
Fig14 After sawing
the bevel on the nose of the tool. Clean UpThe tool is basically shaped now, but since it’s much easier to work the steel before it’s hardened, it’s better to clean up the tool details as much as possible. A cutting edge is the intersection of two surfaces, and can only be as sharp as the worst surface, much like a chain is only as strong as the weakest link. The bevel is relatively easy to clean up even after hardening, but the semi-circular groove is not and there may be some irregularities left from the drill. Pick some moderately fine abrasive, around 180 or 220 and measure its thickness. Subtract twice the thickness from the drill size you made the groove with and select that size drill (or just pick a drill about 1/32” smaller). Fold the abrasive over the drill bit shank and use it like a file to smooth out the semi-circular groove as in Fig15. Fig15 Smoothing the
surface of the groove with abrasive wrapped around a drill.
This is easier to do before the tool is hardened. You can pre-grind the bevel at this point as well. The tool itself isn’t long enough to reach from the V-block to the grinding wheel so you could make a handle and mount the tool, then remove it from the handle during hardening. You’ll have to do this with the Tormek, just jump ahead to the simple sharpening section. What I did instead is to clamp a piece of scrap metal to the tang with a c-clamp and smoothed out the bevel as in Fig16. Fig17 shows the tool at this point from the front, side, and bottom, left to right.
Fig16 Grinding the
bevel using a temporary handle clamped to the tang.
Fig17 The beading
tool from the front, side and bottom after shaping the bevel.
If you want to be able to sharpen the tool by only grinding the bevel, you must get rid of the flat areas next to the groove on the bottom of the tool. You can clamp the tool in a vise and use a flat file to shape the flats into sharp edges. Fig18 shows the result from the front and bottom left to right. Strive to make the points of equal length.
Fig18 The beading
tool from the front and bottom after filing the sides to an edge so that they
from a point at the bevel. Heat TreatingTo harden oil hardening steel it must be heated until it’s red hot (you can also test it with a magnet, when the magnet is no longer attracted to the steel it’s hot enough) and then quenched in oil. I don’t have a forge. I do, however, have a rather large torch that connects to a 20 pound propane tank, which I bought out of envy after a visit by the plumber. Without shielding, it’s barely enough to get the 1/4” steel hot enough. If you have a more modest size torch try using mapp gas instead of propane. Assemble all that things you will need OUTSIDE. You need the torch and a way to light it, quenching oil in a metal can (olive oil is best according to Mark Lacer. If you must use motor oil, be extra careful to avoid the fumes), gloves, and a pair of locking pliers to hold the tool. Fig19 shows all these items gathered together on my concrete patio. Light the torch and direct the flame on to the tool. Don’t try to heat the whole tool, but do try to get the last inch red hot, as in Fig20. Quench the tool by plunging it into the oil, as in Fig21, and stirring for a few moments. When the tool has a chance to cool down, remove it from the oil and remove the locking pliers. Fig19 The set-up to harden the tool with a propane torch. Safety glasses aren’t in the picture because they are always on my face.
Fig20
The nose of the tool is now red hot and ready to quench.
Fig21
Quenching the tool in oil. The tool should be hard now. If you have a file you don’t like much, you can test this by trying to file the tool. The file should skate off without removing much of anything except the black coating. In fact the tool is too hard; it may be so brittle it will break. Tempering will fix this. It is possible to temper the tool by reheating with the torch if you have good color vision or wax indicators. It’s also entirely too possible to ruin the work of hardening by heating the tool too much. I prefer to temper the steel in the kitchen oven. First wash the oil off the tool with soap and water so the smell doesn’t give you away. Heat the oven to 300 degrees and place the tool on some aluminum foil in the middle of the oven as in Fig22. Leave it there for an hour. Then remove the tool and let it cool down. The result is shown in Fig23.
Fig22
Tempering the tool by heating in a 300 degree oven for 1 hour
Fig23
After tempering the tool. SharpeningSimple SharpeningRegardless of sharpening system, you need to handle the tool. This has been adequately explained elsewhere. Make the handle roughly cylindrical if you plan to move on to sharpening the points as it will make turning the handle into a jig easier. As tools with a tapered rectangular tang have become less common, I do want to mention an easy way to prepare a handle for mounting. After turning the handle and mounting a ferule, mount the handle securely in a vise. Select a drill bit whose diameter matched the thickness of the tang and drill straight down into the handle. Then while still turning the bit, tilt the bit to one side so that it elongates the hole, as in Fig24. It may be less stress on the drill bit to do this in a couple of stages, once with the drill halfway into the hole, and once with it all the way down. Then remove the drill and sawdust from the hole and insert the tang of the tool. You can either clamp the tool in a vise and hammer the handle on, or insert the tang by hand, then bang the butt of the tool repeated on a hard surface, letting inertia seat the tool.
Fig24
After enlarging the drilled hole by tilting the running drill in the
handle to fit the shape of the tang. V-BlockTo sharpen the tool using a bench grinder with a V-block, set the base of the tool in the V-Block and adjust the extension of the V-Block so that the entire bevel is in contact with the grinding wheel, as in Fig25. Then turn on the grinder and sharpen the tool. Remember, Oil Hardening steel will lose its temper if over-heated, so grind gently.
Fig25
Sharpening the bevel only of the tool using a sliding V-block and bench
grinder.
TormekThe handle has to be modified, or turned into a jig, so that the tool can be sharpened on a Tormek. Clamp the beading tool in a vise so that the semi-circular groove is down the bevel is up. Use a ½” round file to made a groove straight across the handle, right behind the ferule, as in Fig26. Be careful to keep the file horizontal. Keep filing until the groove is about ¼” deep at the deepest part. Fig26
Modifying the handle to serve as a jig for sharpening on a Tormek (or
clone) by filing a groove across the handle with a ½” file. To sharpen with the Tormek, place the groove in the handle on the guide rod and adjust the projection of the guide rod so that the entire bevel is in contact the grinding wheel, as in Fig27. Then turn on the Tormek and sharpen the tool.
Fig27
Sharpening the bevel only of the tool on a Tormek.
Point SharpeningThe beading tool will work well with just the bevel sharpened, particularly if the bottom edges were tapered to meet the sides of the semi-circular groove. However it will work better if the points are sharpened further. If you do sharpen the points you can omit tapering the sides towards the groove and avoid any tendency to mar the tool rest. Making the JigA sharpening jig, in conjunction with handle modifications, is needed to sharpen the beading tool points. Start by copying or printing out Drawing1. (Drawing1 as a pdf)Trim the drawing and fold it on the indicated line. Apply spray adhesive or a glue stick to the back of the drawing. Fasten the drawing onto construction lumber (such as a 2 x 4) so that the fold is on a corner as in Fig28. Cut the jig out on the bandsaw. It’s probably safer to cut the large bevels first. The result is shown in Fig29.
Drawing1 The pattern for a jig to allow easy sharpening of
the points.
Fig28 After gluing the pattern on to the corner of construction pine.
Fig29 After cutting
out the jig. Clamp the jig in a vise so that the small bevel is up and use a 3/8” round file to make a groove in the middle of the small bevel as in Fig30. It doesn’t need to be very deep, just deep enough to glue in a dowel. The result is shown in Fig31. Cut a 1-1/2” length of 3/8” dowel and glue the dowel into the groove. CA glue might be the most dependable for end grain. The completed jig is shown in Fig32. Fig30 Filing a groove
for a dowel in the top of the jig with a 3/8” file.
Fig31 After filing a
groove in the top of the jig.
Fig32 The completed
jig. Place the jig into the V-Block of your sharpening jig so that the high end is facing the grinding wheel and clamp in place with a small clamp as in Fig33.
Fig33 The jig mounted
into the sliding V-block. Handle ModificationTo start modify the handle similarly as the bevel only Tormek section, only with a smaller file. Clamp the tool in a vise so that the groove is down and the bevel up. Just behind the ferule, make a groove with a 3/8” round file across the handle. Be careful to keep the file horizontal. The groove has to be deep enough to rest on the jig dowel, about semi-circular at its deepest point. Take the beading tool over to the grinder and place the groove on the jig dowel. Adjust the extension of the V-Block so that the entire bevel contacts the grinding wheel as in Fig34. Without changing the V-Block extension, move the beading tool up along the jig as in Fig35. The tool should be heeled over towards its side, and the tool should make about a 15 to 20 degree angle to the wheel. Use a pencil to mark on the handle where the dowel meets the handle at this position. Remove the tool from the jig and wrap a piece of masking tape a couple of times around the handle in between the groove and the mark you just made. Draw a reference line along the handle in line with the top of the beading tool across the tape and part of the handle as in Fig36.
Fig34 Set the V-block
arm extension using the large bevel.
Fig35 Determining the
placement for the point sharpening grooves.
Heel the tool over and push it upwards until the angle is less than 30
degrees.
Fig36 Masking tape
has been wrapped around the handle and a registration mark made across both tape
and handle. Roughly diametrically opposite to the pencil mark, cut through the tape with a knife. Remove the tape from the tool handle and place it on a flat surface. Measure the length of the tape (which will be the circumference of the handle). The math will be easier if you use a metric scale, or a set of calipers that read out in decimal fractions. Multiply this measurement by 0.3 which will set the tool approximately 15° from horizontal. Measure and mark this distance away from the line on the tape as in Fig37. My tape measured 10.5 cm. 0.3 x 10.5 = 3.15. So I measured 3.1 cm away from each side of the line. Return the tape to the handle, using the original mark on the handle and tape to return it to its original position.
Fig37 The
measurements and math to mark the tape to determine the locations of the point
sharpening grooves. Clamp the tool handle in a vise so that one of the new marks on the tape is facing up as in Fig38. Use the 3/8” file to make a groove straight across the handle at the mark for the dowel position, as in Fig39. Repeat to make a groove at the other new mark on the tape. The result is shown if Fig40. Fig38 The set-up to file the point sharpening groove.
Fig39 After filing the first point sharpening groove with a 3/8” file.
Fig40 The finished handle with both point sharpening grooves. SharpeningTo sharpen the beading tool, clamp the jig in the V-Block. Adjust the extension of the V-Block arm so that the large bevel (always set the V-Block with the large bevel because it is easier to match consistently) contacts the grinding wheel when the dowel is in the first groove as in Fig41. Gently sharpen the bevel. Without moving the V-Block, put one of the other grooves on the dowel and gently sharpen the point as in Fig42. Place the third groove on the dowel and gently sharpen the other point. Check to make sure the points are of equal length and adjust if needed. Fig46 shows the sharpened beading tool from the front. Fig43 shows, from left to right, the tool from the side, bottom, and front. The completed beading tool is shown in Fig44. Fig41 Setting the V-Block arm extension using the large bevel which is easy to match.
Fig42 Gently
sharpening the points.
Fig43 From left to
right, the beading tool from the side, bottom and front after sharpening the
points.
Fig44 The completed beading tool. To sharpen the points using the Tormek (or clone) follow the procedure above using a ½” file instead of a 3/8” file to make the grooves on the handle. UsingThe Beading Tool is simple to use. You just hold it horizontally with the groove down, bevel up, and push straight into the wood. The 45 degree angle of the bevel creates a shear scraping cut. The only problem is the higher tool pressure required for a shear scraping cut , with the entire circumference of the bead engaged at once, sometimes produces vibration problems. Fig45 shows the beading tool in use on a fairly sturdy spindle where the tool only has to be pushed towards the center of the work. With thinner work you will have to back up the work with a steady of some sort. You may be able to use your fingers, but I’ve found a UHMW strip with a notch in the side to work much better. A piece of wood with a waxed (or otherwise lubricated) notch will also work. Fig46 shows using the beading tool on a more slender spindle, holding the tool with one hand while providing counter pressure with a notched UHMW strip with the other. Fig47 shows beads cut by the beading tool, off the tool with no sanding. The front piece is cherry; the piece behind it is construction pine. The left-most bead on the pine piece was undercut on both sides to accentuate the bead.
Fig45 Cutting a bead
on a spindle. The groove is down,
the bevel up, and the tool is pushed towards the center of the spindle.
Fig46 Cutting a bead
on a thinner spindle using a v-notched UHMW strip.
Fig47 Un-sanded
spindle beads made with the beading tool.
The front piece is cherry, the rear piece is pine. Using the Beading Tool for faceplate oriented grain is much the same. Again, the tool is oriented groove down-bevel up and pushed straight towards the center of the work. Fig48 shows cutting a bead on a construction pine “bowl”. Fig49 shows the bead that resulted. Again, this picture is off the tool with no sanding.
Fig48 Cutting a bead on faceplate oriented work.
Fig49 The un-sanded
bead formed on a construction pine “bowl”. Tools and Materials*Oil Hardening Steel—1/8” x 1/2” is suitable for beads < 3/32”; 3/16” x ¾” is suitable for beads < 9/64”; ¼” x 1” is suitable for beads < 13/64” Drill press, Drill Bit, and *Combined Drill & Countersink Round, Flat, and Triangular *Files Metal cutting saw *Torch or Forge Locking Pliers such as Vise Grips Gloves Safety glasses Oil in metal container Ferule and Wood for handle Scrap construction pine Starred items are available from Industrial Suppliers such as www.Mscdirect.com; if you’ve never looked you’ll be amazed at how many more drills and files are available than at your local hardware store. AuthorDavid Reed Smith is a basement woodturner who lives, turns,
tinkers, and writes in
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