ARTICLES & REVIEWS
How to Turn a Peppermill
by Mike Cunningham
Making a peppermill is a relatively simple process combining spindle turning techniques and drilling on the lathe.
You will need a roughing gouge, parting tool, various spindle gouges, and a heavy round nosed scraper. In addition you will need a Jacobs chuck on a Morse taper suitable to your lathe, a selection of Forstner bits, and one twist or brad point bit. Finally, you'll need a section of sandpaper and the finish of your choosing. Also, if you're turning a long mill, you may want to use a steady rest. When the turning is complete, you'll need the grinder mechanism. I recommend a stainless steel kit available from Craft Supply or from Chef Specialties . These are available in lengths ranging from 4" to 24".
As for the drill bits, you'll need the following Forstner bits; 15⁄8", 11⁄16" , 1" and 7⁄8". Also a 17⁄64" or 9⁄32" twist or brad point bit.
Choose a blank that will be used in a spindle orientation between centers that's at least 2¼" in diameter and a length appropriate to the size mill you wish to have. The blank should be a bit longer than the anticipated finished length. Mount the blank between centers and rough to a cylinder. Once you have finished the roughing process, square the ends and cut a tenon at each end appropriate to the size of your lathe chuck. Cut a third tenon, at a location that will eventually be the bottom of the mill cap—depending on the overall length of the mill the cap will be about 3" in length, not including the tenon. This tenon should be longer than the previous two, enough for a chuck tenon on the long end of the cylinder and then another portion which will be left on the cap end.
Once the blank is roughed and the three tenons have been turned, remove the blank from the lathe. At this time cut the cap away from the body of the mill, leaving a chuck tenon on the body and the remainder of the tenon on the cap. If cutting on a bandsaw, use a clamp or jig to hold the blank. Cutting round or cylindrical objects on a bandsaw can be dangerous. The blade can grab and spin the work, pulling your hand into the cutting path. I use a handscrew to hold one end of the blank.
You now have two blanks; the long base section of the mill which has a chuck tenon at each end and the shorter cap section with a chuck tenon on its top and a longer tenon on its base. Now you're ready to begin the drilling sequence. Mount the longer base section on the lathe using the tenon on what will be the top of the base. The eventual bottom of the mill will be facing the tailstock. Secure the blank in your chuck and insure that it turns true. Drilling on the lathe should always be done at a very low RPM. Set the lathe speed low, preferably 200–300 RPMs. On most mini lathes this is not possible so use the lowest setting that you have, probably 500.
Insert the Jacobs chuck into the tailstock and insert a 15⁄8" Forstner bit into the chuck, make sure it's secure in the chuck and that the chuck is secure in the tailstock. Slide the tailstock forward until the point of the bit is just shy of the mill blank and lock the tailstock to the ways. Turn the lathe on and using the tailstock advance, slowly crank the bit forward into the turning blank. Drill slowly, take small bites and retract the bit often to clear chips and shavings. Clearing the debris is not overly critical at this stage but later when drilling deep into the blank it is very important to follow this direction. Failure to do so can result in a drill bit firmly lodged deep in the blank with removal ranging from very difficult to an act of destruction.
With the 15⁄8" Forstner bit, drill a hole 3⁄8" deep beyond the tenon. The exact depth of this hole is not an absolute, this hole is merely the area where the ground pepper will exit the mill and also forms the inner diameter of the eventual base upon which the mill will rest. Use a small rule to measure the depth. Remember the depth is measured beyond the tenon!
You've now completed the first step in the drilling schedule. Remove the 15⁄8" bit and chuck the 11⁄16" bit and again move the bit into position. Turn on the lathe and drilling in the same manner, bore a hole 5⁄8" deep beyond the previous hole. This hole or recess will house the actual grinding mechanism and its depth should be as near exact as possible. Step two of the drilling schedule is complete and you're on your way to deep drilling now.
Remove the 11⁄16" bit and chuck the 1" Forstner and again move the bit into position. This is where slow, shallow bites with the bit, and constant clearing of chips and shavings is critical. You'll be drilling through the remainder of the blank to and through the other end. Failure to clear the debris will very possibly, in fact probably, result in the bit becoming lodged deep in the blank. If this occurs removal, as above, can be difficult, often requiring that both blank and bit be removed from the lathe and then the application of quite a bit of brute force in the manner of grabbing, twisting and turning. So, a word to the wise, short bites and clear the debris often!
The purpose of this 1" diameter hole through the length of the mill is twofold. First, this hole provides a passage for the drive rod that connects the cap which the user twists to grind pepper to the actual grinding mechanism in the bottom of the base. It also provides a reservoir for the whole pepper. The hole can be bored through in one of two ways. The first option and the one that I most often choose is the use of a bit extension. This is nothing more than a length of rod with a recess in the end and an Allen screw. The Forstner bit fits into the recess and is held in place with the Allen screw. This effectively extends the length of the bit and enables it to reach through all but the longest blanks. These extensions are available in various lengths, through wood turning supply houses, hardware stores and home improvement centers.
A second method to drill through the blank is to drill approximately half the length from the base end. Remove the blank from the chuck, reverse it by chucking the base end tenon and then drilling the remainder from the top end. The holes will meet and should be dead on, but even if they aren't it's not important. We've already discussed the purpose for this hole and having that in mind, along with the fact that the hole will never be seen or inspected, perfection just doesn't matter.
I use the former method drilling through the blank, however if you have a small lathe, a lathe that's a bit underpowered or don't have a bit extension, the latter is perfectly acceptable. The important thing is to form a hole the length of the blank, how you arrive at that is moot. In fact, some turners hollow through without the use of a bit. Those are the options, you make the choice.
So, we've bored a succession of holes, 15⁄8" followed by 11⁄16" followed by 1". The drilling sequence for the base section is complete. Remove the base from the chuck and set aside.
Now it's time to work on the blank which will become the cap. Chuck this blank onto the lathe using the tenon on what will be the top of the cap. At the base your looking at the short tenon where you sawed or otherwise separated the cap and base sections earlier. Now for a short bit of turning…followed by more drill work. Increase your speed setting to that which is appropriate for spindle turning and form a tenon on the base that is between ½" and ¾" long and of a diameter which will permit it to fit somewhat snuggly into the 1" hole in the top of the base section, the hole that you just finished boring through the blank. You'll want a tenon that will permit the cap to turn freely in the base, but is not too sloppy. However, if you just had to choose between too tight and too loose, loose would win. Remember someone will be turning this cap to grind pepper, you don't want their knuckles to turn white while doing so!
I use a parting tool coming into the tenon at 90° to achieve the correct diameter of the tenon. Initially I only turn a very small portion at the end of the tenon and I stop the lathe quite often to check the fit of the tenon to the 1" opening in the base section. The reason for turning just the end of the tenon??…If I turn it too small I haven't lost the entire tenon, just that portion which I've turned. Once I achieve the correct diameter I turn the remainder of the tenon to this diameter and again check to insure proper fit. Once you're satisfied, put down the turning tool—it's time to drill again!
Place the 17⁄8" Forstner bit into the jacobs chuck and, just like with drilling the base, move the point up to the base. You're going to dill a very short recess into the tenon, only about 1⁄8" or so in depth. The purpose of this recess is to center and house a portion of the mechanism which I call, for want of a better term, the drive plate This drive plate is round and has a square hole in its center which captures the drive rod and turns it when the user turns the cap, this in turn operates the grinding mechanism way down in the base. Now, you'll find that this drive plate is a tad larger than the 17⁄8" Forstner bit—just a hair. Use your parting tool and open the drilled recess just a very small amount to accept the plate. Just take off a very small amount and stop the lathe and check the fit, turn until it fits snug. There will be very little wood remaining around the drive plate. That's fine, the purpose of this is to center the drive plate on the tenon, the remaining wood serves no other purpose.
Okay, one more step in the drill schedule and that's it! Remove the Forstner bit and chuck a 9⁄32" or 17⁄64" twist or brad point bit. You're going to bore a hole completely through the cap, from the tenon through the top. The purpose of this hole is to provide a passage to the drive rod to the top of the cap where the threaded metal cap will attach and control the size of the grind.
You'll find that the manufacturers and sellers of the grind mechanisms often include directions with the product and call for a ¼" hole. My experience has taught me that this is just a bit too small. Let's keep in mind we're working with wood and dry though it may be, it'll change with humidity and therefore will move. If you happen to turn a rather long cap and only provide a ¼" hole, though which the rod will travel and the rod is only a minuscule amount smaller than the ¼" hole, the rod may bind. If that happens, the cap won't turn or at best will be very difficult to turn and the user may not be able to remove the cap to fill the reservoir with pepper, the user will be quite upset with you and this work of art that you've made. So, bore the hole a 1⁄64" or 1⁄32" larger—I use a 17⁄64" bit. This sequence is very straight forward, just bore the hole until you come out the other end. Again, take small bites and clear the debris, Also, take care not to impact the chuck with the drill bit when you exit the wood! This applies when turning the 1" hole through the base as well. Just take your time and you'll avoid this bit destroying occurrence. A hint—when the bit breaks out of the end of the wood, you'll see a small amount of sawdust erupt from around the wood and chuck…you're through!
That's the end of the drilling. Honest! It sounds like a lot and sounds as though it's involved, but it isn't. Three different bits for the base and two for the cap.Okay, drilling is complete and now we can turn. Here we'll turn a simple shaped mill.
As mentioned before, turning a peppermill is straightforward spindle turning. Your finished mill can be as simple as you like or covered with embellishments and surface treatments. You can turn beads and coves, add various elements such as copper, brass, aluminum , powdered and ground minerals, as well as complementary or contrasting wood all contained within turned rabbets and dadoes. The only limit is your imagination.
Place the base section into the chuck using the tenon located at the base, where you first started your drilling sequence. Using a parting tool or small spindle gouge turn away the tenon from what is the top section of the base. If needed, bring up the tail stock for support. The live center will pass into the 1" hole that you drilled but the tailstock itself, just barely touching the shoulder will provide support. On mills longer that 16" you may want to employ a steady rest support. Whichever route that you choose, taking light cuts will remove the tenon without creating problems to the stability of the piece in the chuck.
Once the tenon is turned away, add the cap section by placing the 1" tenon that you turned on the cap into the 1" hole that you drilled in the base. If turned properly, it should fit a bit snug, turning freely without play or slop. Bring up the tailstock and place the point of the live center into the hole that you earlier bored through the cap. If you're concerned about the point of the live center entering too far into the bored hole and possibly enlarging or splitting it, add a washer to the live center point to restrict its entry length. Bring up your tool rest and insure that the bill clears it. Set the lathe to the appropriate speed.
You need to form what I call a waist in the base section of the mill. This waist is the narrow portion of the mill and can be anywhere on the base but I think that it looks best about one third to one half of the way down from the top of the mill. Think of the Rule of Thirds or Rule of the Golden Mean here. When you've determined where this waist is going to be located, mark the approximate center of it with a pencil. Now, let's consider the depth that the waist will be. Remember, there's a 1" hole up the center of the mill. How thick is the mill overall? Let's say that it's 2½" thick, that leaves ¾" between the surface of the mill and hole—go deeper than that and you've penetrated the hole and the blank is no longer a pepper mill blank but a tube with a hole in its side.
I think that we should leave a 3⁄8" thick wall between that drilled hole and the outer wall, so we want to remove 3⁄8" of material at most at the narrowest part of the waist. I set my calipers for 1¾" and using a parting tool, I turn away material at the point that I marked until the calipers tell me that I've nearly reached that depth. I want to leave a bit for refinement with a scraper. That will be the narrowest part of the mill base. Now, using spindle gouges I shape the mill base to get a flowing, pleasing shape from above the waist, through the waist, to the base, keeping in mind that I still must turn the curved shoulder at the top of the base, where it flows to the opening and meets the cap.
Once I have this rough shape, I move to the top of the base and what will be the shoulder. Again using a spindle gouge—usually 3⁄8"—I begin turning a curved shoulder from the side into the top end of the base where it meets the cap. Usually I keep the 1" opening as the very top and as the narrowest part of the top of the base and then do likewise with the base of the cap, so that the two meet at a point where they are equal in diameter. Having said that, you can depart from that idea and turn the top of the base so that the 1" opening extends upward as a sort of tenon and the cap sits upon that. As I said before, your imagination is the only limit in the design.
The base section is now turned to near completion and it's time to move to the cap. I shape the cap, usually in an approximate ball shape with the mid-point between the top and bottom as the widest diameter. Once this shaping is complete I move back to the base section and using gouges and my heavy, wide, round nose scraper refine and finish the base. Once this is complete I sand both sections, usually starting with 120 or 150 and moving through 320.
Now for the finishing touches. Move the tailstock and remove the cap. Look at the cap, the very top where the tailstock sat will be a bit rough. So will the very top of the base section around the perimeter of the 1" opening, where the cap sat. This is easily remedied. With the base section still mounted in the chuck, restart the lathe and using very light cuts, refine the rough edge around the 1" opening with a small spindle gouge and finish with sandpaper.
I often wet sand with Watco Danish oil using wet/dry paper in 320 grit. I like the finish this gives and if you don't apply overly liberal amounts of oil, is a relatively neat operation. I often apply the oil to the entire base by hand, then sand with the paper wet with the same oil. I sometimes keep a rag on the ways just beneath the piece to protect them from the oil, or failing to do this, I simply wipe the ways when I'm finished. I've been wet sanding work on the lathe for years and unlike those that use too much oil, I don't have oil streaks up the nearby walls and on the ceiling.
The base is nearly finished. The only remaining step is to turn away the tenon still on the bottom. Remove it from the chuck and replace the standard jaws that you've been using with the smallest dovetail or spigot jaws that you have. Remount the base section by expanding the jaws into the top, 1" opening. Bring the tailstock up for support. The tailstock will extend into, the opening, beyond the tenon. Using very light cuts with a sharp parting tool of gouge, turn away the tenon. Lightly sand and oil the base.
Now to finish the cap. Mount the cap, by holding it in the chuck jaws by the 1" tenon on its base. The area around the hole where the tailstock sat will be a bit rough. Using a freshly sharpened gouge, clean up this area and then finish with sandpaper. Remember that the metal cap threads onto the drive rod and will be wide enough to cover the remaining hole which will only be slightly larger than the one that you drilled through the cap. Apply some oil and remove. Any jaw marks in the tenon can be sanded away and the tenon will be out of sight inside the base.
The only steps remaining are those related to installing the mechanism. This is a quick, straight forward operation which only requires the drilling of four small pilot holes, two in the base and two in the cap tenon and then the installation of four wood screws. I use lubricating wax on the screw threads to ease the install and always keep in mind that the screws are small and can easily be broken—don't over-tighten.
As I mentioned at the beginning, the mechanism comes in sizes ranging from 4" to 24" in nearly 2" increments. Rather than trying to buy a mechanism to the exact specification of the mill that you wish to make and then trying to turn and finish the mill to that length, I have a very simple tip. Buy a mechanism that's 2" longer than the anticipated finished mill. As long as the mechanism rod is longer than the mill that you complete, it can be sized to fit. It's a simple matter of measuring to determine the length needed, then cutting the drive rod to the correct length by removing the required amount from the non-threaded end using a hack saw. Gently peen the end and install the mechanism. After installing the mechanism, test it by tightening and loosening the cap and insure that the grinding portion closes and opens.
One last hint—while I don't apply finish to the interior of the mill (the 1" hole that we bored through) I do run a shotgun bore brush through to remove any loose pieces of wood shavings.
I usually apply three coats of Watco allowing 24 hours drying between coats and then buff on the Beall.
If you'd like additional material on peppermill turning; look for books, articles and videos by Richard Raffan, Dale Nish, and Nick Cook
. . . Mike Cunningham
© 2005 by Mike Cunningham. All rights reserved.
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