Domed Cove Box. Materials: Dry stable hardwood, straight grained with pronounced end grain, about 3+ square and 3+ long Sandpaper Finish of choice

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1 Domed Cove Box Michael G. Stafford I don t know who first turned a box where the sides were curved in to form a waist or as we like to say in woodturning, coved. I started gradually turning boxes with an hour glass shape and as I shortened them the cove became more distinctive. The cove also makes a tight fitting box easier to open. Over the years I have seen examples of coved boxes by other turners and I offer these instructions as my take on a design that belongs to no one in particular. Materials: Dry stable hardwood, straight grained with pronounced end grain, about 3+ square and 3+ long Sandpaper Finish of choice Tools: Center finder, awl Spindle roughing gouge #3 Hunter tool Fingernail ground spindle or detail gouge Square and round nosed scrapers Parting tools (ultra thin is useful for maintaining grain alignment) 3/8 beading parting tool Skew chisels Calipers, internal and external Depth gauge, measuring rule Let s get started. Page 1 of 7

2 1. Select a nice knot free piece of dry wood about 3+ square and 3+ long. Mark the centers on each end with an awl. Score the diagonals on the drive center end with the band saw by holding the wood in V-shaped cradle. Mount the wood between centers and turn it round. Form a tenon/spigot on each end sized to fit a four jaw chuck with a parting tool or beading/parting tool. Check the size with the calipers. In this case the tenon/spigot on each end is about 3/16 long. 2. Measure the length of the blank between the spigots to layout for the parting cut to separate the lid and body. For this box proportions are equal between the top and bottom. Allow about 5/16 for the body flange and another 1/8 for the parting cut. The top and bottom will each be slightly less than 1 in the finished box so part the box about 1 1/8 from the end that will be the top. Page 2 of 7

3 3. Mount the lid section in the 4 jaw scroll chuck and tighten it securely. With a fingernail ground spindle gouge true up the blank on both the sides and end. Remove as little wood as possible while truing up the end of the lid to minimize grain mismatch. Begin hollowing the lid using the spindle gouge. Then smooth up the surface with a round nosed scraper or Hunter tool. Check the depth frequently. Don t hollow much deeper than 9/16-5/8. Remember the finished height of the lid is going to be about 7/8. If it is too thin it will check easily while sanding. 4. Use a square scraper to cleanly cut the lid flange. The goal here is to cut the lid flange parallel. With inside calipers check to see that the sides are parallel. Smooth the bottom of the lid with a skew used as a scraper taking light cuts removing fine curls to ensure that the lid is in the same plane after hollowing. Sand the inside and finish. Be careful to not distort the lid flange by sanding. Page 3 of 7

4 5. Chuck up the body of the box. True up the side and end using a spindle gouge. Use a parting tool or beading/parting tool to cut the flange upon which the lid will fit. The object here is to cut a tapered spigot/tenon where the lid will just begin to go onto the box flange. See the picture on the right below. Do not cut the box flange so that the lid fits at this time. The hollowing process could release tension in the wood that would make the blank oval and result in an ill fitting lid. 6. Hollow the box body with a spindle gouge just like the lid. Check the depth frequently to make sure the bottom is the same depth as the inside of the lid plus the body flange; about 9/16-5/8. Use a scraper or Hunter tool to smooth the bottom. Sand the inside of the box to a fine finish. Once the body is hollowed it is time to fine tune the box flange so the lid can be jam fit for turning. Use a sharp skew, parting tool or beading/parting tool for this operation. Check the fit frequently and remove dust until the lid jam fits on the body without splitting. If the lid fits too loosely on the box flange a piece of tissue can be inserted between the two to make for a tighter fit as shown here. Sometimes a wipe with a damp sponge can also help a loose lid fit tightly enough for turning. It never hurts to secure the lid with tape at the join if the fit is insecure. Page 4 of 7

5 7. Mark the ends of the cove measuring from the center join line. The cove should begin about 5/8 from the center on both the top and bottom of the box. With the lid jammed onto the box body use a spindle gouge to refine the shape. Use the tail stock in support for safety to prevent accidentally knocking the lid off during shaping. With a spindle gouge form a shallow cove centered on the join between the lid and the bottom of the box. Try to retain the start lines as reference marks for forming the domes that will be on the top and bottom. 8. Remove the tailstock and if the jam fit is not perfect secure the top to the bottom with masking tape in the cove. Form a smooth curved dome on the lid of the box ending at the line that marked the beginning of the cove on the side. Using the wing of the fingernail ground spindle gouge will help remove any ripples and ensure a smooth continuous curve. Remove the tape, sand and finely finish the inside Page 5 of 7

6 9. Remove the tape and adjust the fit of the lid with a sharp skew used as a scraper or with a parting tool. Strive for a nice suction fit. Finely sand the lid and the coved sides. Power sanding at slow speed will help form the smooth curve and finish on the lid. Slow down the lathe speed when sanding. Apply finish to the inside of the body of the box, the body of the box and the top of the lid. Sometimes multiple coats of finish can tighten up a loose fitting lid. 10. Remove the body of the box from the chuck. In its place chuck up some scrap wood for a jam chuck to reverse turn the body of the box. Strive for a nice snug fit on the jam fit that holds the box in place without splitting the box. Jam the box body on the waste block and bring the tail stock up for support. Use a spindle gouge to form a dome on the bottom of the box that mirrors the one on the lid. Page 6 of 7

7 11. Finish shaping the bottom removing all ripples and bumps from the domed shape. Once again the wing of the spindle gouge can help form a smooth curve. The goal is to have the bottom shaped exactly like the top of the lid. Sand and finish the bottom just like the top. 12. Apply a nice coat of wax and buff it to a nice shine on all surfaces of the box. Sign the bottom and include the wood species. Now go turn your own domed cove box. Page 7 of 7