Shop Made Collet Helps You Get a GripComments (0)
This article is from Issue 5 of Woodcraft Magazine.
If you’re looking for a fast, easy way to secure workpieces in your lathe when turning bottle stoppers or other dowel-based projects, look no further than this simple shop-made solution.
I read with interest in the March issue the article on turned bottle stoppers, Project No. 7, by A.J. Hamler. Turning bottle stoppers can be both fun and gratifying, whether done for pleasure or profit. However, it can also be frustrating and sometimes even dangerous.
My first experience with turning stoppers was to load a blank between centers, turn the profile, and then attempt to drill a hole squarely in one end for a dowel that would hold a cork. Unless the end result is to intentionally create a stopper that tilts or sits off-center on the bottle, this is not a preferred method.
So I bought a standard metal chuck for my lathe, drilled the dowel holes in the blanks, glued 3/8" dowels in the blanks and then used the chuck and the tailstock to hold the blank while turning. This worked fine as far as holding the blank steady goes, but once the turning was finished I discovered the chuck jaws had bitten into the dowel, deforming it beyond recognition and making it impossible to glue a cork to the maimed surface. In Project No. 7, A.J. got around this problem by using a longer dowel and cutting off the damaged portion.
However, during the period of trial and error on subsequent stoppers, I came up with a better way to hold the dowels attached to my turning blanks. My solution was to turn a wooden a chuck sized to hold stopper dowels. This would be a four-jaw chuck – or, more correctly, a collet – that could be used with or without the lathe’s tailstock. I didn’t make any detailed drawings of my concept; I just decided what it should look like, how it should perform, and got down to business using what scrap material I had on hand that would work well.
For this project, the basic design of the collet has been refined a bit from my original, and uses materials that most turners generally have on hand. However, there’s one required piece of hardware you should find first.
As you’ll see a bit later, the jaws of the collet grip the stopper dowel by sliding a metal ring over the jaws and snugging it down tight. Metal rings are easy to come by, but because there’s some slight variance in inside diameter depending on the ring supplier – and because you’ll be turning your collet to match the size of the ring – it’s best to get the ring first.
Most hardware stores carry an assortment of metal rings, usually back where they keep chains and hooks, so you can find one to fit whatever size collet you make. Most stores carry both steel and brass rings (Fig. 1). You’ll probably find that brass rings are more consistently smooth around the inside edge – steel rings often have a distinct joint where they’ve been welded. Try to find a ring with an inside diameter of 11/8", but if you can’t, make your collet to fit the size of the ring that’s available.
Before we start cutting wood, it’s important to note that you don’t have to stick to the exact sizes of stock used here. This project is freeform in size and shape – much like turning bottle stoppers in general – so you can make your collet pretty much any way you like.
Making the blank
To create the turning blank for the collet, the first step is to cut a rough circle of hardwood a bit larger in diameter than your lathe’s metal faceplate (Fig. 2). The faceplate shown here measures 3", so the hardwood circle is 5" in diameter, a good working size. Adjust your blank size according to the size of the faceplate you’ll be using. You can use just about any wood you like, but you’ll find that standard 2" x 6" x 6" hard maple turning blanks work well.
For the collet neck blank, a 3" x 3" x 31/2" piece of hard maple will work nicely. A solid piece of stock is preferable, but lacking that, you can glue up the neck blank from two thinner pieces. Mark the center of the neck blank (Fig. 3). For easier turning, knock the corners off the blank on the table saw or bandsaw to create an octagonal shape.
Drill a pilot hole in the center of the neck blank, and countersink and drill a pilot hole in the round blank. This is a good time to drill the round blank for screws to attach the faceplate – it’ll be more difficult once the blank is glued up.
Apply glue to the neck and attach it to the round blank with a screw (Fig. 4). For the size of stock used here, a 3" screw worked perfectly.
Time to turn
Attach the faceplate and mount the completed blank on the lathe, checking for clearance on your tool rest (Fig. 5).
Turn the basic shape of the collet any way you like, forming a general taper down to the outer end that just matches the size of the inside diameter of your metal ring (Fig. 6). Be careful at this point – you don’t want to turn the neck too small, or the ring will slide too far down. Continue turning your taper until you can slide the ring about 3/4" down the neck, but no more.
(If you should accidentally turn the neck too much, you can still fix it. Because the neck is tapered, if you make it too small simply cut a bit of the neck off so that the ring slides down only 3/4".)
Give the turning a good sanding, increasing grit size till the workpiece is nice and smooth. The ring will probably slide down slightly more than 3/4", so don’t be too aggressive when sanding, as you don’t want to drastically change the neck diameter.
Creating the jaws
Next, you’ll need to drill two 1/4" holes, perpendicular to each other, through the sides of the neck 11/2" from the outer end. If you’ve used solid stock for the neck, you can drill the holes anywhere around the circumference, but if you glued the neck blank from separate pieces, don’t drill along the glue joint, or it may weaken the collet when the saw kerfs are cut a bit later.
You can drill the holes using a hand drill with the workpiece still mounted on the lathe if you’ve got a steady hand. However, a simple jig mount to hold the workpiece gives you greater control and accuracy by drilling the holes on a drill press (Fig. 7). A jig mount allows you to unscrew the faceplate/collet assembly from the lathe as a unit, and cradle it securely for drilling and cutting the collet jaws.
Pencil a set of 11/2" perpendicular lines down the neck, and drill through the neck and into the jig mount. (This will leave a hole in the jig mount, which we’ll use a bit later when cutting the slots for the jaws.)
Return the assembly to the lathe.
Now, here’s where I found a real use for the metal chuck I’d bought to turn bottle stoppers. With the chuck in the tailstock, I put in a 3/8" bit, turned on the lathe and drilled down the center to the perpendicularly drilled 1/4" holes (Fig. 8). Mark the depth on your drill bit with masking tape to avoid drilling too deeply.
Remove the collet assembly from the lathe and return it to the jig mount. Slip a short length of 1/4" dowel through the neck and into the hole drilled earlier into the jig itself. This will align the hole perfectly vertically, making it easy to cut a true kerf on the bandsaw (Fig. 9).
If you chose not to make a mounting jig, you can use a backsaw supported on the tool rest to make perpendicular cuts aligned with the holes through the sides of the wooden collet blank. However, making the jig mount is well worth the time it takes, especially if you plan to make additional collets to accommodate different dowel sizes.
Return the assembly to the lathe once more, and slip a folded piece of sandpaper into the jaw slots to clean them up a bit and remove the sharp outside edges (Fig. 10).
Do a test fit of the metal ring, and slide a short length of dowel into the collet. Pull the ring down the neck to close the jaws and secure the dowel. The ring should slide down to between 3/4" and 1", roughly halfway between the holes and the end of the neck.
At this point, your bottle stopper collet is complete, but a few coats of finish will not only make it look good, but will help protect it from finishes you might use when making stoppers. The collet shown here has several coats of Hut’s friction polish.
Using the collet
My one metal faceplate is now and forever a dedicated piece of my shop-made collet. I doubt that the collet would ever be exactly centered again should I remove it from the metal faceplate and then re-attach it at a later time. To preserve the accuracy of your collet, I’d suggest buying a metal faceplate that you can leave permanently attached.
While I made my collet to fit the size dowels I use, you can size yours to hold any size. And it’s not limited to use in turning bottle stoppers. I use mine to turn finials and other small pieces that require a dowel in one end for attaching to a larger piece.
Turning anything in this collet with the tailstock on the other end for support is extremely safe. The blank butts right up to the end of the neck, and the collet holds the piece firmly after the tailstock is moved back to finish turning the top of the piece.
The best part is that the collet holds a bottle stopper blank securely, but it doesn’t lock it rigidly in place. Unlike a metal chuck, which bites deeply into the dowel, the circular wooden collet jaws have a bit of “give” to them. Accidentally catch a chisel or gouge when using a metal chuck, and you’ll dig a good-sized divot into your turning at best, or snap the dowel at worst – possibly sending the unfinished stopper flying. Catch a gouge on your workpiece while using this wooden collet, however, and your workpiece stops momentarily, giving you time to pull back on the chisel before ruining the piece.
This collet is also very friendly for applying a finish to a turned piece. Since the dowels I use are about 1" long, I’m able to loosen the jaws and pull the turning out ¼", then retighten the jaws. This small space allows me to get to the bottom of the turning with a finish, so all finishing is done on the lathe. Occasionally the turning is not quite centered when pulled out from the collet, but that can be quickly remedied by pushing it in just a hair with the jaws tightened.
From start to finish, this inexpensive shop-made collet has put the fun back in turning bottle stoppers and other small projects – and taken away most of the risks of injury and the frustrations of failure.
Jon T. Hutchinson
Jon T. Hutchinson is the editor/associate publisher of Markee Magazine, a trade publication for and about the U.S. film and video industry. He’s been an avid woodworker and furniture designer for 30 years, at times for profit, but always for the love of the craft. He and his wife live in Deland, Fla.
(Note: The collet in this project is made of hard maple, but any hardwood will work.)
2" hardwood blank, sized slightly larger than lathe faceplate
3" x 3" x 31/2" hardwood blank
Brass or steel ring with 11/8" inside diameter
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