Turning Pendants with the Richard Joyner Eccentric Backer Plate

Transcription

1 Turning Pendants with the Richard Joyner Eccentric Backer Plate Vaughn McMillan August 2010 As the result of a great tool sharing effort by my friend Jonathan Shively at I was recently given the opportunity to test drive a cool little lathe jig made by Richard Joyner. (Richard goes by the name of sailing away on the forums at The jig, which I ll call the backer plate, allows you to turn a thin piece of wood into a flat round shape, then you can offset the plate to turn off-center accents to the piece. The backer plate is made of two parts: I ll call them the base and the indexing plate. The base has eight holes, tapped with a 3/8 thread to fit a standard bottle stopper mandrel. One of these holes is centered, but the others are all offset varying distances from center. It also has four holes for thumbscrews that are used to attach the indexing plate to the base. The indexing plate has twenty-four holes around the perimeter of the plate, in 15 degree increments. These holes are threaded to accept the thumbscrews that attach it to the base. Although they aren t shown in the photo below, the backer plate I used also had four countersunk holes on the indexing plate that allow you to attach a waste block to the plate with flathead wood screws. (A feature I didn t use in my testing.) Apologies in advance for the quality of this photo. I m working on getting a better one.

2 Double-sided tape is used to hold the workpiece onto the backer plate. You should use a high-quality carpet tape or turner s tape if you want to avoid flipping miniature Frisbees around your shop. Although you can mount the workpiece directly to the aluminum backer plate, I followed Ed Davidson s recommendation in his Pendant Turning videos ( and used a waste block, which allowed me to round the edges of the pendant more easily. I ve seen suggestions to use melaminecovered MDF for the waste block, but since I had some scrap Baltic birch plywood sitting around, I used that instead. I used a hole saw on the drill press to cut a few waste blocks. The size isn t critical I just made them smaller than my intended pendants, but large enough to have ample flat surface for the double-sided tape to hold onto. These were cut with a 2 saw, so the waste blocks ended up between 1 ¾ and 1 7/8 in diameter. Next, I attached the backer plate to the bottle stopper mandrel (which was already mounted on the lathe), using the center hole in the base.

3 Then I stuck the waste block onto the backer plate with double-sided tape. Here s the waste block ready for the tape and here I m using the live center in the tailstock to center and press the waste block onto the backer plate:

4 Now it s time to attach the workpiece. For this project, I m using a blank I glued up out of some scrap walnut and padauk I had laying around the shop. To help the tape hold the workpiece in place, I used a flat tip in my live center. You could also use a small piece of wood on a pointed live center.

5 A bit of tape on the workpiece and it s ready to be pressed onto the waste block:

6 You might have noticed my blank isn t very round. No worries I have a big yellow machine that ll make it round pretty quickly. A couple minutes (or less) later, and I ve got the blank round

7 and the edge rounded over. The edge has a little bit of tearout, but I ll fix that in a minute. First I want to true up the face, so I remove the tailstock

8 then get things flattened up. In this case, I used a Ci1 Mini carbide tool from Easy Wood Tools. Light cuts are necessary, since everything is relying on the tape to hold things together. I didn t get to picky with the surface I used 2 sanding disks on a drill motor to clean things up. (I m no purist. Sandpaper is another turning tool.)

9 A quick trip through the grits to 400 (I spent more time switching disks on the drill than I did with the actual sanding), and the results looked like this: Next, I needed to drill an off-center hole for the leather thong or string that the pendant will hang from. To do this, I removed the backer plate from the bottle stopper mandrel and picked one of the offset holes in the base.

10 I decided to use hole number 6. Note that in order to use some of the holes, you must remove one of the thumbscrews. For hole number 6, I didn t need to do this. Here s what it looked like after I remounted it on the bottle stopper mandrel. It s easy to see it s no longer centered on the lathe spindle: Time to turn on the lathe and check things out. Doesn t this look like fun? What would possess someone to stick sharp tools into that blurry mess?

11 Ah well, the first task drilling the hole will be in the center of that blur, so it ll be pretty easy. With a 3/8 spur bit in a drill chuck in the tailstock, I check to confirm the hole will end up about where I want it: Looks close enough for lathe work. I set that lathe speed at about 500 RPM, and slowly advanced the bit into the workpiece. When I saw the light-colored shavings (indicating I was drilling into the waste block), I knew I d drilled far enough.

12 The end result is an off-center hole, just like I d planned: Next, I used a sharp detail gouge to chamfer the edge of the hole. I stopped the lathe for this photo. Otherwise, it d be a lot blurrier.

13 After a little bit of sanding the chamfered edge of the hole, it s time for some accents on the pendant. Between the offset holes on the base and the 24 possible variations with the indexing plate, there are a lot of different designs you can do. For this one, I kept things simple, and just left everything set as I had it for the hole. I ll just cut three shallow grooves in concentric circles around the hole. To do this, I first used a lumber crayon to get a rough idea where I wanted to make the cuts. Using the tool rest as an anchor point, I rotated the piece by hand and drew my guide lines:

14 Next, I used the Ci1 Mini again, but this time I held is at an angle to the face, so I d only be using the corner of the carbide cutter to make the grooves. The tool is flat and level on the tool rest, but angled in relation to the face of the workpiece. Since the carbide cutters tend to work better for me at higher speeds, I cranked the lathe to about 900 RPM for making these cuts. Too fast, and the tape won t hold. Too slow, and it ll be more difficult to get a clean cut. When cutting the grooves on the off-center workpiece, it s very important that you take light cuts. Very light cuts. And of course, face protection is a given. After three quick cuts, here s what the pendant is looking like:

15 You ll notice I didn t follow my lines exactly. If I d wanted exact lines, I wouldn t have used a crayon to mark the lines, huh?

16 You can see that the two outer lines go beyond the edge of the pendant. That s why the light cuts are co critical. One slight catch on the edge of the pendant and it ll go flying. After a bit of sanding to remove the crayon marks, the pendant is pretty much done: At this point, the pendant is ready for finishing. Although I didn t finish this one, you could use just about anything friction polish, any of the wipe-on oil or polyurethane finishes, sprayed shellac or lacquer. You could even use spray paint if the wood s not all that attractive. Here are a few pendants and test pieces I made in my playing around with the backer plate. These were all quick and dirty test pieces, so I didn t go to heroic efforts to make the cuts and finished surfaces perfect.

17 All in all, the Richard Joyner Backer Plate is a handy jig, and it offers many possibilities for creating unique turnings. Since this tutorial is already longer than your average college term paper, I ll stop at this point and save the discussion about using the indexing holes for another tutorial. I hope this one has been of some help. - Vaughn My website is at Visit me and some other fine wood artists at