Outdoor bench with bent lamination curved legs

[Alan Lightstone]

Aaron's thread got me really interested in building one of these, so I'm now figuring out what wood to use, and how to build this:

484454

Not my original idea, but really love the design that Aaron showed on his thread: https://sawmillcreek.org/showthread.php?297723-Legs-for-a-midcentury-bench

I got the okay from SWMBO (especially on outdoor stuff) to not paint it. She would love for it to have the rough appearance of this piece, but I'll insist on the curved bottom legs and it will have slats like the bench above, not a solid top. It looks like 6' wide, as that is a dimension that we can easily get cushions for. I want to challenge myself with a different type of design/construction:

484455484456

So thinking a dark wood for the legs. My first thought is Peruvian Walnut, but not sure how that will do outside. Sapele for the slats might be nice, but SWMBO thinks it's too red. Perhaps White Cypress as a good outdoor wood, though don't know if I can get it around here.

Any thoughts regarding whether I can get the Peruvian Walnut to bend enough for the legs? And how thin to make the laminations.

[Mike King]

According to this site: https://www.timberblogger.com/peruvian-walnut/ Peruvian walnut has good steam bending properties but I suspect it would be difficult to get air dried stock. That's not necessarily a deal breaker for steam bending, but it may limit the radius of bends you can achieve. A bigger issue is that the site says it isn't great for outdoor applications...

Mike

[Richard Coers]

Not any direct answers for you, but the best thing you can do for exterior bench legs is build a masking tape dam around the bottom of the legs and cast a 1/4" thick cap out of epoxy on the end grain. The epoxy prevents moisture from wicking up into the end grain. Very few woods retain their original color when exposed to UV light. So don't judge the fresh color.

[Jamie Buxton]

Re laminate thickness -- read the thread you posted.

[Alan Lightstone]

According to this site: https://www.timberblogger.com/peruvian-walnut/ Peruvian walnut has good steam bending properties but I suspect it would be difficult to get air dried stock. That's not necessarily a deal breaker for steam bending, but it may limit the radius of bends you can achieve. A bigger issue is that the site says it isn't great for outdoor applications...

Mike

I wasn’t interested in steam bending, just bent laminations. I’m not sure if kiln dried would be an issue for that versus air dried with bent laminations. I agree, might be hard for me to get air dried Peruvian Walnut.

Of course I could choose another better outdoor wood, and stained it, but that wood does have a beautiful grain and color for the bench.

I’ve been there, done that with stream bending and while I have a full set up to do it, I just find it too unreliable to get identically radius pieces. The spring back just varies too much piece to piece.

Of course I’m sure other people are better at it than I was.

Of course if it turns gray, it would probably please SWMBO as the house is gray as is a bunch of our outdoor furniture

[Alan Lightstone]

Re laminate thickness -- read the thread you posted.

I’m not sure why I posted that question. I remember the discussion from the other thread. Just a brain fart, I guess, on my part. 🤦

[Mark Rainey]

Alan, I am not sure Aaron overcame the 1/32 inch thickness for each of the laminates. I have done bent laminations with a 3/32" laminate. 1/16 is thin, 1/32 is really thin. I asked if any members used 1/32 inch laminates and there were no responses.

[Alan Lightstone]

I could make 1/8" laminate pieces with ease. Probably 1/16" too.

I can't imagine trying to make 1/32" pieces.

I'll clearly have to get some wood, and make some test pieces of varying thicknesses and see what works, what splits, and perhaps what species I need to use.

First step will be to make a few test pieces to see what radius curve looks good.

[Mike King]

I could make 1/8" laminate pieces with ease. Probably 1/16" too.

I can't imagine trying to make 1/32" pieces.




https://www.accu-slice.com/accu-slice-system.html

[Mark Rainey]

https://www.accu-slice.com/accu-slice-system.html

Mike, visited the website. Interesting. Looked at several of his videos. When sawing 6 inch wide cherry 4 feet long, he pushes the wood thru at 10 inches per minute using an 8 teeth per inch blade. Unusual...very slow. Perhaps this is why his boards have very little bandsaw marks. I cannot find any recent reviews from anyone using this product.

[Mike King]

I have no experience with it. However, one of the professionals on the Felder Owners Group has used the system to cut veneer from very expensive logs with great success.

it isn’t cheap…

[Alan Lightstone]

Odd, because their website says that’s it’s not compatible with the metric miter slot on Felder bandsaws.

[Mike King]

Members of the FOG own equipment from vendors other than Felder.

there are other options for controlled resawing including building appliances to hold stock against the resaw fence. Check this thread https://sawmillcreek.org/showthread.php?299145-Slicing-Veneer-with-the-Amazing-Woodmaster-CT

with a good blade, such an appliance, and good technique you should be able to saw 1/32nd laminates with little trouble.

proper technique is face joint between each resale, then plane the laminate in an appropriate planner. Lunchbox planers excel at this task as they have rubber feed rollers rather than serrated ones…

[Alan Lightstone]

My thoughts have now shifted to these issues:

1.) How to make the tight radius curve in the legs without splitting. Definitely looking to put my smaller bandsaw blade on for this to make the forms, then my 1" resaw blade for the laminates.

2.) Doesn't look like a fun glue-up with the multiple long pieces going around 2 curves. I'm thinking a U-shaped lamination with the front and back feet. I'll join it to a top piece of solid wood with conventional joinery. I've been thinking that using my large vacuum bag and two mating forms might be my best procedure for that. I can't imagine getting a sufficient number of clamps on this shape, especially for the tight curves on the front and back of the legs.

3.) For glue - either epoxy or urea formaldehyde glue (Unibond 800) or Ultra-Cat Powdered resin glue. For 1" thick legs, that's a heck of a lot of 1/16" laminates. If I can't bend 1/16" that tightly, then possibly have to double the number of thinner laminates. Wow that would be a difficult glue-up.

[Mike King]

A vacuum bag, even at sea level, will not pull enough pressure for that bend. You will need a bunch of clamps to make it happen.

Mike

[Alan Lightstone]

A vacuum bag, even at sea level, will not pull enough pressure for that bend. You will need a bunch of clamps to make it happen.

Mike

:(
How about a vacuum bag with a few external clamps around the bend? I've seen that approach online. Never tried it.

[Christopher Charles]

Should be a fun project. Have you considered white oak-good outside wood and should grey nicely if left unfinished?

[John Kananis]

I'm not sure it would work out as well as it does while I'm sitting on the couch thinking about it but (that radius is just so, so tight) I would cut 1/8 inch boards, steam them and then clamp to forms with a polyurethane glue to take advantage of the moisture). Just let them sit there, clamped up, for a day or two.

[Mike King]

:(
How about a vacuum bag with a few external clamps around the bend? I've seen that approach online. Never tried it.

A couple of years ago, a fellow workshop participant used bending with a form and clamps outside the bag in a workshop with Adrian Ferrazutti. Still, you won't be saving anything because you need a lot of clamping pressure to bend the laminates AND close the gaps between them. I don't think that a vacuum bag gets you anything for your application.

First thing to do is make a form that approximates the radius of the bends you are considering. Then, resaw some laminates of whatever species you are thinking of using and see what thickness of laminate you need in order to get them to conform with the form. That will tell you if the species, form, and equipment you have are compatible with your objective.

I still think you might be better off with steam bending. Have you tried double bending? You heat the wood, bend it one way, then bend it the other. This breaks the lignon bonds in the wood. You can put the piece back in the steam box to reheat, then bend the wood more easily.

I've not done this myself, but Michael Fortune has a lot of experience making tight bends like you desire with that method. You will most likely need air dried stock though. And best if it isn't too dry.

Mike

[Mike King]

I'm not sure it would work out as well as it does while I'm sitting on the couch thinking about it but (that radius is just so, so tight) I would cut 1/8 inch boards, steam them and then clamp to forms with a polyurethane glue to take advantage of the moisture). Just let them sit there, clamped up, for a day or two.

First of all, I seriously doubt that 1/8th inch laminates will make those bends. Second, steaming requires significant time to dry -- a day or two wouldn't likely be successful in achieving the shape -- you'd be completely relying on the glue to hold the pieces in shape. Polyurethane glue is a mess to deal with as well and I doubt that even though it is foaming up that the glue would be of sufficient strength to hold the laminates in the proper shape.

Mike

[John Kananis]

Fair statement on clamping time and the glue is messy but I do "think" it would work - just brainstorming though.

[Alan Kalker]

White oak cut into very thin laminations.
Agree that a rigid urea formaldehyde glue will be needed. Wear a good mask.
Also agree you’ll need to do this on a form with clamps.
Stain it.
‘Finish with Epifanes finish (found in marine stores). It’s a pain to use but it’s the only exterior finish I’ve ever seen hold up through tough seasons.

[Alan Lightstone]

I'm working on forms today. Don't have the right wood, though.

I've also thought of making the corners out of solid wood, and dominos or tenons to connect them to the legs. I've also thought of doing the legs in several pieces like that, then laminating one strip of thin laminate on each side to hide the joints. Very thin laminate, I would think, would be very easy to glue to that. Not sure about longevity, though.

Not against white oak. Once grey, SWMBO would probably like that a lot.

I have experience with Epifanes and System 3 Marine varnish. Epifanes was a real pain to apply. The System 3 much easier. But I'll have to see. It's not the initial finishing I'm concerned about. Refinishing could be hell.

I need to get a better resaw blade. My present one is strangely 1" with 2TPI. Thinking a 3TPI blade would make smoother cuts, though at $400 plus shipping for a Lenox Tri-Master Carbide 1" 3TPI blade, I'm thinking I'll make do with my present blade.

[Mike King]

1" 2TPI should be fine. Actually getting a 3TPI blade could result in worse cuts as the gullet space becomes packed and causes friction...

An option is to ebonize whatever wood you pick for the legs...

Mike

[Alan Lightstone]

So, did some trials. 1/8" white oak and cypress both can't remotely bend around that 1" radius curve (both kiln dried, my local supplier laughed at the concept of getting air dried).

The thinnest I was able to make was 1/32". Both the 1/32" white oak and cypress both can make that 1" radius curve, with some difficulty.

Really not worth the effort for me to make 1/32" veneer in the shop. I'll likely buy some, and try laminating that. But using solid wood pieces and joining them together, perhaps with a veneer piece on the outside layer to hide the joint is sounding more and more appealing by the minute.

I wonder how they made that bench in the photo?

[Alan Lightstone]

So now that I've decided to go with solid wood pieces for the curved portion of the legs of the bench, I've got a problem that I'm having trouble getting my head around.

This is what I am looking to make for the curved portions of the legs. They'll be attached (probably via loose tenons) to straight 1" thick, 3" wide white oak boards.
485075
485076

Those are from a test piece I just made. The inside curve was made with a 2" Forstner bit, and the outside curve initially on a bandsaw, and refined on a disc sander. My 1/8" bandsaw blade clearly has too many TPI and burns every cut of these, but if refined with a router and/or sanded, that shouldn't be an issue.

I can't imagine I could make 6 of these per bench and have them be identical using this method. The outside curves will certainly be inconsistent, and the flat sections I had to cut on the bandsaw as my table saw can't accommodate 3" thick boards clearly won't be perfectly perpendicular. I don't have a CNC machine.

I'm thinking somehow to use my router table and a template, though I don't have bits pattern bits with 3" cutting length (I do have some 2'1/2" ones). But how do I make repeatable pieces that are this small with these small radius curves? Whoever made that original bench did a tough job beautifully:
485077

Totally open to good suggestions.

[Mike King]

Option 1 -- it's handmade, and the curved pieces are separated by a lot of real estate, meaning that the slight variations you get won't likely be noticeable...

Option 2 -- scribe it and work to the scribe line with a rasp and sandpaper.

Option 3 -- you've always wanted a shaper, right? Pattern shape the piece with a spiral helix cutter.

Mike

[Alan Lightstone]

Option 1 -- it's handmade, and the curved pieces are separated by a lot of real estate, meaning that the slight variations you get won't likely be noticeable...
Probably true, but I'm concerned about the ends of the corners not being at exactly 90 degrees, so the piece would rock.

Option 2 -- scribe it and work to the scribe line with a rasp and sandpaper. Basically did that with the sample piece, although with a disc sander and an oscillating spindle sander.


Option 3 -- you've always wanted a shaper, right? Pattern shape the piece with a spiral helix cutter. Yes, but frankly, for whatever reason, they kind of scare me. Plus, no room unless I replace my automated router table with it.


I'm trying a M-Power Router Jig with the small circle attachment next. Kinda bulky, especially with my large Festool router, but started to make a template last night and I'll see how that goes. The interior angle I can repeatedly make with a Forstner bit, so it's really the outside angle (which I agree, I bet no one would notice) and most importantly how to get the ends to be perfectly perpendicular to each other that I'm fighting with now. Trying to figure out how to cut out these pieces on a tablesaw with a sled instead of the bandsaw.

[Kevin Jenness]

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.

[Jim Becker]

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.
I agree with this technique.

----

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.

[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.

----

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:
485287
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.

485567485569

Here's the first test piece:
485570485571

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.

488090

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!!!! :eek: 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.

[Mel Fulks]

You could put some blocks under them. Look at some pics of , I think , Chippendale chairs , I think called “block foot”. Yours would have to
be more modern ,but the precedent is set. Yours would be “The Precedent Of The United States”.

[Alan Lightstone]

So, after many months of work, I finished construction of the bench:
497887
The corners of the legs are not gorgeous, but strong and functional. Lots and lots of glueing, and making all those 1" half laps all identical was clearly a challenge, even with the jig I made.

Now on to finishing. It's made of white oak. As much as I love the look of marine spar varnish over epoxy (a reasonably durable outdoor finish), this bench will be sitting outdoors in Florida. The Titanic deck chair I made had that finish and looked awesome for about 2 years, but when it degraded, refinishing it was a nightmare. This would have the same issues.

So looking forward to suggestions as to the best way to finish it.

[Mark Rainey]

Alan, you did it! Persistence. I know of no finish that will stand up to the Florida sun for any length of time. Use an outdoor oil, recoat every few months & get a cover for that bench - you worked too hard on it to let the sun ravage it.

[Christopher Charles]

Great looking bench and I agree an oil finish, not a film finish would be less disappointing in the end. The FL sun is a tough one to beat. Regardless, I’m sure you will enjoy!

[Alan Lightstone]

Recommendations for an oil finish? I'm assuming something that doesn't have a film finish that dries.

I understand some have a mildewcide built in, which would be a plus here.

First look I found Cetol Marine, but I can't tell if it's a film finish. Used on boats pretty extensively, I hear.

I have Tung Oil, but think that's not a good choice. Boiled Linseed oil?

Wondering about Rubio Monocoat also.

Really looking for something with UV protection, and mildewcide would be a big plus.

[Greg Parrish]

Great looking bench Alan. I’m also loving the nice view of the shop. Looks like an amazing setup and awesome place to spend time. Thanks for sharing this project. Lots of inspiration here.

[John Kananis]

Alan, the bench came out really nice - it's going to look really great with a finish I think. Idk about Rubio, it really doesn't like the water I think. Odie's oil and wax maybe if you're looking for that type of finish and reapply one a year or more in your geography but I would absolutely get a canvas cover for it if it's going to sit in Florida sun all day. Everything eventually turns gray out there without proper care.

[Aaron Liebling]

Love it Alan! For the record I failed at the bent laminate and went with straight legs instead. I couldn't get the right angle I needed not enough clamping. I still have a bunch of the sheets cut and I'll try some other project with them eventually.

497986

[Kevin Jenness]

Consider Cetol for finish. Supposed to have good uv protection with ease of recoating.

[Carl Beckett]

subbing - curious to learn what finish you decide on.

I have done a handful of outdoor projects/woods and have yet to find a finish I can recommend. One was a replacement door on an old house - after many recommendations went with epoxy and it turned into a disaster. It didnt penetrate well and mildew under the film.

I have used BLO on white oak outside - required redoing after the first NE winter (seems to just dry out) - but maybe it will improve after regular reapplication? Tung oil did a 'little' better - those were both smaller projects and I was able to soak the pieces in oil.

A deck (mahogany decking) I did with Penofin oil based. It attracted mildew but otherwise did 'ok'. An outdoor arbor I used a water based 'nano' finish which didnt make it one winter before needing more. (Behr deck stain at the orange store is just plain awful)

Net net - I havent found any water based outdoor finish to recommend. Oil based stains had done 'better' for me and I will continue with those unless you find something that works better. An annual refresh though.

YMMV (I hope, and I hope you share that mileage so I know what to try next...!!)

[Mark Rainey]

I have been using General Finishes Outdoor Oil. It seem to work but I recoat often. And sometimes have to use bleach solution if if rains for several days in a row without sunshine to dry things out.

[Aaron Liebling]

I went with tung oil for mine. This is a bench that will be on a porch in LA. No direct sun or rain. I'm guessing it will need reapplication every year, but that's doable.

[Alan Lightstone]

Love it Alan! For the record I failed at the bent laminate and went with straight legs instead. I couldn't get the right angle I needed not enough clamping. I still have a bunch of the sheets cut and I'll try some other project with them eventually.

497986
Looks great, Aaron. I was really wondering about yours. We made some different choices for joinery. I think both have a nice unique look.

Yup, doing those legs was quite an ordeal. Can't imagine what they would have been like to do bent lamination with 32+ 1/32" pieces. Yikes..

SWMBO will certainly want a matching bench. Don't know if I have that in me. Would love to move on to other projects.

Congrats, Aaron. Beautiful bench.

[Alan Lightstone]

Consider Cetol for finish. Supposed to have good uv protection with ease of recoating.
Does Cetol form a film finish, though?