Mahogany GliderComments (0)
This article is from Issue 64 of Woodcraft Magazine.
Rock away the dog days of summer in this stylish seat.
Overall dimensions: 283⁄8"w × 583⁄4"l × 343⁄4"h
Other than a tall glass of iced tea, nothing complements a summer day better than a comfortable seat. This attractive outdoor glider fits the bill. Unlike standard benches or chairs, this two-seater hangs on long swing arms mounted on heavy-duty bearings that allow it to sway with the gentlest push.
Despite its complex appearance, this project isn’t that difficult when you break it down to its subassemblies. As you’ll see, I used biscuits and screws where I could and reserved the mortises and tenons for the spots requiring more substantial joinery. A plunge router equipped with an edge guide can make quick work of the larger mortises in the front and back legs. To rout the narrow back rails for the splats, I devised a simple, stable jig that guarantees straight, centered slots.
This project would look good in a variety of exterior-grade hardwoods, including teak or white oak. I chose mahogany because of its reputation for standing up to rough weather, and I applied several coats of marine varnish for a finish befitting a wooden boat. (To prevent your project from turning grey prematurely, I recommend setting it out of direct sunlight and covering it or bringing it indoors when the cold weather sets in.) Paint will hide the grain, but it would offer better protection and permit you to use a less expensive wood, such as cedar or cypress.
Build the base
1 From 8/4 material, mill the stock for the legs (A), top rails (B), middle rails (C), bottom rails (D), stretcher (E), and stretcher braces (F). Referring to the Cut List, rip the parts to width. Cut the stretcher to length, but leave the other parts 1" oversized in length for now.
2 Referring to the Base Exploded View, above, arrange the legs (A) and rails (B, C, D) to make two base side assemblies. Orient the parts to suit the grain, and then label each part using pencil or chalk. Note the directions of the miters on the ends to prevent any miscuts.
3 Set your mitersaw to 10°, and cut the legs and rails to the lengths listed in the Cut List. Use a stopblock to ensure that the matching parts are the same lengths. (Note: Setting the miter angle once and flipping the stock to cut opposing angles–rather than re-setting the saw in the opposite direction–will guarantee that the parts fit tightly together. To control tear-out on the bottom face of the board, set the parts on a scrap piece of plywood or MDF when cutting.)
4 Reposition the legs and rails. (Slide the middle and lower rails up as needed so that they fit tightly between the legs.) Mark a line across the center of each joint on the outside faces of the stock for biscuit slot and screw references. Next, lay out the hole locations for the glider bearings on the inside faces of the top rails (B) and the screw holes on the outside faces of the middle rails (C).
5 At the drill press, use a 11⁄8" Forstner bit to bore the 9⁄16"-deep holes for the glider bearings on the inside faces of the top rails (B). Next, drill the 3⁄16" clearance and 3⁄8 × 1⁄4"-deep counterbore holes (for the plugs) in the middle rails.
6 Position the legs and rails on your bench with the centerlines facing up. To cut the paired biscuit slots, flip the biscuit joiner fence down to locate a #20 biscuit slot about 1⁄2" below the top face of a board. Cut the first slot at each joint location, flip the stock, extend your biscuit centerlines to the opposite face, and then cut the second slot.
7 Dry-assemble a base side assembly (A-D) to rehearse the clamp up. (A few scrap wood cauls can help. See Photo A.)
When you’re ready, apply glue (I used Titebond III), insert the biscuits, and then assemble a side. Wipe away squeeze-out with a clean, damp rag. When the glue has cured, repeat with the other side assembly.
8 Rout the edges of both base side assemblies (except the bottom ends of the legs) and the edges of the stretcher (E) and stretcher braces (F) with a 1⁄4"-radius round-over bit. Then finish-sand through 220 grit.
9 Attach the stretcher (E) to the middle rail (C) using 21⁄2"-long deck screws.
10 Flip the assembled base (A-E) upside down, measure the diagonal distance between the bottom rail (D) and stretcher (E), and trim the stretcher braces (F) to fit. Nip the bottom tips of the braces even with the bottom edge of the bottom rail. Using a drill press and angled support block set against your fence, drill 3⁄8" counterbore holes and 3⁄16" clearance holes in the top end of both braces. Now attach the braces with deck screws, where shown in Figure 1.
Now for the swing arms
1 From 4/4 stock, mill the four swing arms (G) and eight end blocks (H) to the sizes listed in the Cut List.
2 Glue the end blocks to the arms. (Note that the blocks attach to one face at the top end, and the opposite face at the bottom.) When the glue dries, lay out the hole locations and the radiused ends where shown in Swing Arm Detail, page 37. (Note: To save time and avoid errors, I made a full-sized pattern to lay out the holes and radiused ends.)
3 At the drill press, bore the 3⁄4 × 3⁄4"-deep counterbores through the swing arms (G) and the 1⁄2" through holes through the end blocks (H).
4 Bandsaw the ends of the arm assemblies, staying just outside your lines, and then finish up with a belt or disc sander. Rout the edges with a 1⁄8"-radius round-over bit.
5 Insert a 3⁄8-16 × 2" hex head bolt (replacing the 11⁄2"-long kit bolts) into each glider bearing, install a nut, and then press a bearing into the holes in the top rails (B). Secure each bearing to the rail with three #6 × 5⁄8" kit screws, as shown in Photo B.
6 Trim the nylon bushings to 3⁄4", and then slide one into the top ends of each swing arm assembly (G, H). Referring to the Base Exploded View, page 37, and Glider Bearing Detail, attach the swing arm assemblies to the base assemblies. Put the base aside for now.
Make the bench sides
1 From 8/4 material, mill stock to make the front legs (I), armrests (J), rear legs (K), and slat supports (L). Mill the seat stretchers (M) from 4/4 stock. (Note: If your stock allows, you can get both rear legs from a 73⁄4"-wide board, as shown in the Rear Leg Detail, page 40.)
2 Make a full-sized pattern of the rear leg (K) on 1⁄4"-thick hardboard or plywood. Include the locations of the rail mortises and the hole for the glider bearing. (Note: When cutting the rear leg pattern, consider using your tablesaw to practice the tapered and stopped cuts.) While you’re at it, make the armrest (J), seat stretcher (M), and slat support (L) patterns.
3 Position the rear leg pattern’s bottom edge against a jointed edge of your stock and trace it out. Label the top and bottom ends of the leg on your stock to avoid accidentally mortising the wrong end. Flip the pattern over and end-for-end, then trace the other leg, again positioning the rear leg pattern’s bottom edge against a jointed edge. (If you were able to trace both legs onto a single board, use a bandsaw to separate the two.)
4 Rip a strip of scrap plywood to approximately 7" wide. Without moving the fence, affix a rear leg to the plywood with double-sided tape so that its uncut front edge overhangs the edge of the plywood. Now make the cut, as shown in Photo C. Repeat with the other rear leg.
5 To determine where to stop the cuts on the back face, raise the blade to the necessary height, set a wood block against the front-most teeth, and draw a stop line on your saw’s table. Draw a line on the edge of the leg blank where the inside of the upper taper meets the lower leg. Next, set the fence 21⁄2" from the blade. As you saw the first edge, stop the cut in front of the stop line, hold onto the leg blank, and turn off the saw. Now flip the leg blank end over end, and make the second stop cut, as shown in Photo D. Repeat the process with the other rear leg.
6 Complete the stop cuts on both rear legs (K) with a bandsaw or handsaw, and then clean up the front and rear edges as needed.
7 Referring to the Front Leg Detail, page 39, and Rear Leg Detail, lay out the mortises and centerpoints for the glider bearing and screw holes on the front and rear legs (I, K) and the mortises on the armrests (J). At the drill press, bore the 11⁄8 × 9⁄16"-deep stopped holes for the glider bearings and the clearance holes and counterbores in the front (I) and rear (K) legs on the legs’ outer faces. Remember that the leg assemblies are mirror images of each other.
8 Outfit your plunge router with an edge guide and 1⁄2"-diameter upcut spiral bit, and rout the 1⁄2"-deep mortises in the front and rear legs.
9 Align the armrest pattern against the back end and bottom edge of an armrest blank, and trace it on your stock. Repeat with the second blank. Referring to the Armrest Detail, page 39, lay out the tenon where shown.
10 At the tablesaw, cut the tenons on the front legs (I) and the armrests (J) (Photo E). Use a bandsaw or dovetail saw to trim the angled armrest tenon to width. Now saw and sand the rounded ends of the front and rear legs and armrests. Put these parts aside for now.
Rail Mortising Jig
This simple jig guarantees straight, centered mortises. Because router bases vary, you’ll need to make a few test cuts to set the stopblock. Record the mortise's stop and start points on the top so that you can reposition the jig for the next slot.
Build the back
1 Mill the top rail (N), bottom rail (O), and front rail (P) from 5/4 stock. Mill the vertical splats (Q) and horizontal splat (R) from 4/4 stock. Cut the parts to the dimensions in the Cut List.
2 Referring to Figure 5: Back and Splat Detail, use your tablesaw, outfitted with a miter gauge and auxiliary fence, to cut 3⁄4- thick × 1⁄2"-long tenons on both back rails (N, O) and the front rail (P). (Note: I rounded the ends of the tenons with a file to fit the mortises. Alternatively, you can square off the ends of the mortises with a chisel.)
3 Clamp the top and bottom rails together face-to-face, and lay out the mortises on the inside-facing edges, referring to Figure 5, right.
4 Make the slot cutting jig shown above. Using a plunge router equipped with a 5⁄8" O.D. bushing and 3⁄8" upcut spiral bit, rout the mortises in the top and bottom rail, as shown in Photo F.
5 Using a thin strip of scrap wood, lay out the curve on the top rail (N) where shown. Bandsaw just outside of your line, and then sand smooth.
6 Cut the vertical splats (Q) to the dimensions listed in the Cut List. Referring to Figure 5, lay out the tenons along the top and bottom ends of one splat. Using a tablesaw and miter gauge, cut a 3⁄8 × 11⁄4 × 3⁄8" long tenon on the top end of each splat. Repeat with the remaining splats.
7 To cut the angled tenons on the bottom ends of the vertical splats, adjust your miter gauge to 10°, and cut a narrow tenon shoulder on one edge of each splat. (I used a stopblock on the rip fence to ensure this cut was exact.) Next, set the gauge to 10° in the opposite direction, rotate the splat so that the uncut edge touches the table, and cut the opposite shoulder.
8 Adjust the blade’s bevel angle to 80° (10° from vertical), and set the miter gauge perpendicular to the blade. Referring to the saw kerfs on the edges, set a stopblock and cut a 1⁄8"-deep kerf to establish a shoulder on one face of each splat.
9 Reposition the miter gauge on the other side of your blade, rotate the splat so that the uncut face touches the table, and reset the stop. Now cut the final shoulder, as shown in Photo G.
10 Without changing the blade angle, clamp a splat into a tenoning jig, and cut the rear cheek on all six splats. Now reset the jig and blade height, and cut the front cheeks, as shown in Photo H.
11 To taper the splats, make a pair of guides from two 9 × 12" pieces of 1⁄2"-thick plywood or MDF. Saw a 2° taper on the edge of one guide and a 4° taper on the edge of the other guide to create 88° and 86° corners, respectively.
12 Position the 2° tapering guide in a crosscut sled. Insert a shoulder-positioning strip between the guide and sled fence, and place a splat against the guide (top end toward you), with the shoulder resting on the strip. Locate the guide and splat so that the blade grazes the splat’s back edge. Now taper one edge of each splat, as shown in Photo I.
(Note: The two innermost splats are tapered on their outer edges only.) To make mirrored parts, cut the edge of one splat facedown, and the other faceup.
13 Position the 4° guide in the sled in the same manner, and cut the opposite tapered edges on the four outer splats (Photo J).
14 Cut the horizontal splat (R) to the dimensions listed in the Cut List. To join the horizontal splat to the inner splats (Q), I used my mortiser to cut the mortises in the splats. To do this, I set the vertical splats on a 10° wedge to accommodate the tapered edge, and then cut tenons on the horizontal splat to fit. (Alternatively, you can join these parts with a pair of #20 biscuits. Adjust the splat’s (R) length accordingly.) Rout the long edges of the horizontal splat with a 1⁄8" round-over bit. Finally, glue the horizontal splat between the two inner splats.
15 Rout the edges of the rails (N, O) with a 1⁄4" round-over bit and the splats (Q) with a 1⁄8" round-over bit. Finish-sand the rails and splats through 220 grit.
16 Dry-assemble the top rail (N), bottom rail (O) and splats (Q, R) using a leg to maintain the 10° angle of the bottom rail (Photo K). When you’re confident that everything fits, apply glue to the mortises and tenons, and assemble the back.
Assemble the rest of the bench
1 Arrange the parts needed to make up both bench sides: the front legs (I), arm rests (J), rear legs (K), and seat stretchers (M). Position each stretcher between the appropriate front and rear leg pair, and mark its location. Referring to the Front Leg Detail, page 39, and Photo L, cut two #20 biscuit slots, 13⁄4" apart, in the back edge of each front leg and in each stretcher’s front edge, so that the stretcher is flush with the inside edge of the leg. Cut a single biscuit slot in each rear leg and the back end of each stretcher.
2 Dry-fit and clamp each seat stretcher (M) between its mating front leg (I) and rear leg (K). Position the armrests in place, and refer to the tenons to mark the locations of the mortises on the front edges of the rear leg (for the armrests) and on the bottom edges of the armrests (for the front legs). Using a plunge router equipped with a 1⁄2" upcut spiral bit and an edge guide, rout the 1⁄2"-deep mortises in the rear legs (Photo M), and the 1"-deep mortises in the armrests.
3 Test-fit the side assemblies (I, J, K, L). Round over the edges with a 1⁄4" round-over bit, and then assemble, as shown in Photo N.
4 Glue and clamp the back assembly (N, O, Q, R) and the front seat rail (P) between the seat side assemblies.
5 Referring to Figure 6, below left, trace a fair curve along the top edge of the slat supports (L). Cut and sand to shape. (Note: Position the top edge of the slat support flush with the top edge of the front rail [P].) Drill pocket holes in both ends of each support, and attach them between the bottom back rail (O) and front rail (P) with glue and 13⁄4" pocket screws. Plug the holes to keep out moisture.
6 Mill the stock for the seat slats (S), but leave the slats 1⁄2" oversized in length for now. Rout the top edges of each slat with a 1⁄4" round-over bit, as well as the bottom edge of the foremost slat. Now trim the slats to fit between the seat stretchers (M).
7 To space the slats evenly across the seat, measure the distance from the back rail (O) to the front edge of the seat rail (P), add 1⁄2" for an overhang, subtract the total width of the slats, and then divide by 7. (The gap should be about 1⁄4".) Rip spacer strips to the calculated width, and position them between the slats. Mark across the positioned slats to identify the centerlines of the slat supports underneath.
8 Drill 3⁄16" clearance holes and 3⁄8" diameter counterbores into the slats along the slat support centerlines.
9 Fasten the slats (S) to the slat supports (L) using 11⁄2" deck screws. (You’ll need to partially disassemble the project for finishing, but at this point you can attach the seat to the swing arms and give your glider a test run.)
Finishing touches and assembly
1 Disassemble the bench and base from the swing arms and remove the swing arm hardware.
2 Using a drill press and 3⁄8" tapered plug cutter, cut wood plugs from remaining stock.
3 Working one section at a time, select a matching plug, apply a bit of glue in its hole, align the grain on the plugs with surrounding grain, and then lightly tap the plug in place. After allowing time for the glue to dry, saw or rout away the bulk of the excess material, and then sand the plugs flush.
4 Using the Corner Bracket Pattern, page 45, make a full-sized pattern, and trace four bottom brackets (T) onto 3⁄4" stock. Make four support blocks (U). Saw and sand the brackets to shape, and then glue them to the front and back rails where shown in the Bench Exploded View, page 39. Center the support on the rail/bracket joints to reinforce the joint.
5 Finish sand the glider through 220 grit. (Provided that you cleaned up the subassemblies as you worked, this step should go quickly.)
6 To protect the mahogany from the elements, I applied seven coats of Epifanes Marine Varnish. As per the instructions, I thinned the first coat 50%, and used less thinner (about 10% less) with each subsequent coat until approaching full-strength. After each application, wait 24 hours, scuff-sand, and then wipe off any dust before applying the next coat.
7 Attach nylon gliders to the legs. (The spacers will keep the legs out of standing water and make the piece easier to move.)
8 To reassemble the glider, first reattach the glider bearings to the base’s top rails and to the bottoms of the front and rear legs. Next, slip a washer and nylon bushing onto each exposed bolt on the top rails, and then attach the swing arm to each bolt with a washer and 3⁄8" nut. Finally, carefully set the bench on the base’s stretcher, slide the washers and nylon spacers onto the leg bolts, and then attach the swing arms, followed by washers and nuts.
9 Pour yourself a glass of iced tea and give your new glider an inaugural swing.
About Our Author
Brian Stauss resides in Indian Springs, Alabama, has been woodworking for over 35 years, and has been a member of the Alabama Woodworkers Guild since 2002. In addition to serving as the webmaster for the Guild, he serves as a workshop supervisor and teaches classes to other members.
Special thanks to the Alabama Woodworkers Guild for the use of their Education Center and Shop for the photo shoot.
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