Outdoor bench with bent lamination curved legs

[Alan Lightstone]

Glue up the leg assemblies with the inside radius cut in otherwise square blocks. Do the outside curves afterward with a template and flush cutter.

Sounds like a plan.

I've made a jig, similar to Woodpeckers Corner jig, which I have, but doesn't go up to a 2" radius. I think Kevin's approach should work great. Thanks.

Biggest issues then are working with 3" thick wood blocks (exceeds table saw capacity). I'll sort that out next.

[Alan Lightstone]

I agree with this technique.

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My concern here would be weak grain structure on a piece cut from a solid block unless the inside radius is kept to a minimum so there is a lot of "meat" to the component. A bent lamination is a lot more complicated, but it doesn't have that potential problem in addition to joinery that can fail. Doing the joinery version requires stout components to withstand normal seating stresses as well as the effects of weather.

I worry about this too, but the legs will be 3" wide x 1" thick. Three of them supporting a 5-1/2 foot bench.

Leaning towards white oak. Those corner pieces seem very strong, so I think it will be all about joinery. Was hoping to do loose tenons (although size might be somewhat limited as I only have the Domino DF500). If that looks too week, I might have to do true mortise and tenons. Not something I've done before, but is doable.

[Wes Grass]

Looks like a lathe job to me. 3 pieces sawed from each cylinder. Or separate blocks clamped on a faceplate. A bit of a pain either way.

I did a 3/8-1/2" with cherry at about 1/32. Came out 'ok', but I couldn't quite get the bend pulled together solid even with clamps over the bag. They'd been steamed in an egg poacher and wrapped up on the form for a loooonnnnggggg time. And bent along the grain.

[Alan Lightstone]

Looks like a lathe job to me. 3 pieces sawed from each cylinder. Or separate blocks clamped on a faceplate. A bit of a pain either way.

I did a 3/8-1/2" with cherry at about 1/32. Came out 'ok', but I couldn't quite get the bend pulled together solid even with clamps over the bag. They'd been steamed in an egg poacher and wrapped up on the form for a loooonnnnggggg time. And bent along the grain.

Don't have a lathe, but interesting.

I'm gluing together 4 pieces of white oak now. Routing with the template I built to get the outside curves is next, then onto the router table with a pattern bit. Then the drill press for the inside curves. Sand the inside surfaces with the oscillating spindle sander, the outside surface with the disc sander. Finally the miter saw, as my table saw can't cut that thick a piece. Boy, a lot of steps...

Nothing easy about this. It's a beautiful design. I really wish I knew who built it, and how they made those pieces.

[Wes Grass]

I just caught the 'rocking' comment. So the bottom needs to be formed with a slight hollow to it?

[Alan Lightstone]

I just caught the 'rocking' comment. So the bottom needs to be formed with a slight hollow to it?

No, but if the corners aren’t perfectly perpendicular.

[Wes Grass]

'Upon further review' ...

I suppose even if slightly convex it's going to flex in the middle and bear the load at the ends. Maybe a bit wobbly if you wiggle it, but fine once you plant your ... on it.

[Alan Lightstone]

Well, routing with the template was terrifying. The 1-1/4"D x 2"L pattern bit I had was insanely loud in the router table, even after turning its RPM down to the recommended setting. Kinda terrifying, but I ran the 3" thick board through the router after bandsawing it about 1/8" from the line, but it left awful tearout. So this was a non-starter. I ran it through the bandsaw again, then used my 6" disc sander (was really pushing its capacity, but barely made it) and it made a nice looking curve.

I guess the disc sander will be my approach. Hopefully I can get 6 identical pieces (actually will need 12 as I am making 2 benches), but one at a time. Now the challenge will be to cut off the square ends at exactly 90 degrees and the right length with my miter saw, as my table saw doesn't have 3" capacity, especially on a sled.

[Alan Lightstone]

OK. Next question. It's about the joinery options. Here's where the curved pieces stand now:
Bench Leg Curved Pieces 2.jpg
My original plan was for the shape seen with the blue outline. I was planning on using my Domino 500 to make loose tenons for the connection, but I'm concerned that it won't be strong enough to handle the weight. Plus not at all sure how to get the Domino to make the mortises on that small curved piece.

A second option, seen at the top with the red outline, is to elongate the curved pieces to give a larger wood piece to have the mortises live in. Should be a little easier to use the Domino. And I would think stronger.

A third option, would be to make true mortise and tenons. Again, not terribly easy on the curved pieces. Piece of cake on the straight wood that would connect to it.

A fourth option, I guess, would be to use dowels. Probably the far easiest approach, but would it be strong enough?

[Kevin Jenness]

Your method leads to short grain on one side of the corner block and makes it difficult to cut, join and square up the pieces. A better approach in my opinion would be to start with a large enough blank to have the grain running at 45* to the legs, bore the center hole, square up the joint surfaces, add dominos or dowels, glue up the frame and bandsaw and sand the outer curves last. That will leave a square outer corner to register your joinery and to clamp against. If your tablesaw won't reach high enough, finish the square cuts with a handsaw or use the bandsaw and true up with a hand plane, sanding block or your disc sander.

[Kevin Jenness]

Here's another way to make a curved corner, by the shop I used to work at. https://www.instagram.com/p/BP8gQDHgZF3/ Probably not right for this application, but another way to "skin" the curve.

[Alan Lightstone]

Here's another way to make a curved corner, by the shop I used to work at. https://www.instagram.com/p/BP8gQDHgZF3/ Probably not right for this application, but another way to "skin" the curve.

Thanks, Kevin. I still might wind up using this approach to veneer entirely around the legs, though with a dark gray stain I'm not sure I need to with SWMBO color choices.

[Alan Lightstone]

OK. Made some progress. I got creative and decided to use my router and a bunch of Bondo to make a jig that could hold the curved pieces securely in order for me to make Domino mortises in them. The 1/8" shim is there to make taking out the snug pieces more easily.

Curved leg piece with mortises for Domino 4.jpgCurved leg piece with mortises for Domino 1.jpg

Here's the first test piece:
Curved leg piece with mortises for Domino 2.jpgCurved leg piece with mortises for Domino 3.jpg

I used 8mm mortises, 15mm deep into each side of the curve pieces. Now on to making some test straight pieces to see if this is sturdy enough to hold two people on the bench.

I thought of breaking out my Leigh MFT Pro and making true mortises and tenons, but that would again be a complicated jig, and barely fit in the maximum size that it could handle. But that may be Plan B.

[Alan Lightstone]

So one step forward, one step backward. I came up with a process of making the legs. I scrapped the above jig, as it was too inconsistent with making the domino mortises. I starting cutting and using 3"x2"x2" wood blocks, which I cut mortises into one side, then glued the corresponding long board to them, was then able to clamp the piece to make the mortise at right angles to it, glued the second long board to it, and finally, was able to use a Forstner bit to make the inside 2" diameter curve, and a bandsaw and disc sander (boy I really need a large edge sander) to make the outside curve. They came out looking pretty reasonable, but not as pretty as the picture of the original above.

Bench Legs 1.jpg

Now the problem. Due to a change in design, and frankly a mismeasurement, they are about 3" too short. So, perhaps I'll make an end table out of them, but they are out for building the bench. Aaarghh!!!! Each leg took about a week to build. It's a 10 step process at least. Oh well.

[Jim Becker]

Could be an opportunity to make the benchtop more of a "floating" construction visually.