Category Archives: Roubo Bench

Knockdown Roubo Bench Construction Details

With the recent upgrade of the knock down Roubo workbench, there have been requests to learn more about the construction details used.  There are many ways to build a bench, so here was the criteria I needed in this one:

  1. The primary purpose was and is to display our line of tools, and provide a work space for their demonstration.  It needed good work holding ability, and stability was important.  This also meant it had to have enough weight to keep it in place regardless of the type of floor it was setting on.
  2. It needed to be portable enough to fit into a car, along with all the other items traveling along to the shows.
  3.  It needed to be attractive and also have traditional workbench appearance and function.

The Roubo style of bench is my favorite.  My original bench is in this style and has been serving my needs very well.  I was familiar with the construction techniques and felt it would be a simple job to carry this into the knock down bench.

To a large degree, the wood determined the size of the bench.  I had two Honey Locust beams, one 12″ x 12″, and the other 6″ x 12″, both 8′ long, cut into 3″ thick planks.  The top is made of one 12″ and one 6″ plank glued together to make an 18″ wide top.  Leg lengths were cut off these planks so it finished out at a little over 5′ long.

The legs are about 5 1/2″ x 3″, and are as small as I would want to go. Stretchers are resawn, and are about 5 1/2″ x 1 3/8″.  Having a tall stretcher is more is more important than width to prevent wracking.

The bench breaks down into five basic components, plus the shelf.  There are two leg assemblies which consist of one front and one back leg plus stretchers.  One assembly also includes the leg vice.  These each have a top stretcher to add rigidity and allow for securing the top in place.  This top stretcher is not as tall to allow for lag screws to pass through into the top. (I used Spax brand screws.)  The front leg is mortised into the top with 1″ tall x 1″ thick.  I wanted something substantial because the leg vise is exerting pressure against the top and needed to be solid.  Interestingly, I have found that there is no need to screw the top in place; it stays put just with the tenons.

Bench with top removed. Note holes for lag screws.

Tenon on front of leg.

The stretchers are assembled with draw bored pins;  two per tenon on the lower stretcher and one for each top  stretcher.  These were made of white oak.

Stretcher with draw bored pins. Also note the bolt hole counter bored for a 3/8″ bolt.

The long stretchers are assembled with short tenons and bed bolts, purchased from Lee Valley tools.  I modified the bolts by tapping a hole in the end and inserting a machine screw to serve as a handle when assembling.  The holes in the legs are counter bored and also are offset to the inside of the stretchers.  That way. the hole for the barrel nut did not go through the stretcher, and it looks nicer.  However, I did glue a block to the inside of the stretchers to add material since the hole is so close to the edge.  These blocks also serve the purpose of supporting the shelf.

Stretcher joint showing the offset hole and added block on the stretcher.

Assembled leg joint. Note the machine screw that serves as a handle on the barrel nut when assembling the joint.

When I added the Acer-Fererous screw and Benchcrafted criss cross, I could no longer use the bed bolt in the vice leg.  I am going to try it without it and see how it does.  This may need to be rectified in some way in the future, but we will see. Also, the nut was screwed to the leg using two lag screws.

Nut mounted to the back of the vice leg.

All in all, this bench has worked out very well.  I also use it for demonstrations and find it can be used for vigorous work without any trouble.  The top is the heaviest part, and probably weights somewhere around 60 to 70 lbs, which is manageable.  And it is very compact and fast to set up.  I am quite pleased.

Disassembled leg assemblies and stretchers.

 

 

Knockdown Roubo Bench

This small Roubo style work bench was built several years ago for use at woodworking events away from the home shop.  Primarily it is the show bench used to display and demonstrate the Red Rose Reproductions line of tools.  With a top size of 60″ x 18″, it is small enough to be portable, yet big enough for serious work.  It will easily break down into five pieces:  The top, two leg assemblies, and the two long stretchers.  While perfectly adequate for shows, I decided to do some upgrading.  Pictured here is the bench as originally made in front of the larger permanent bench that stays in the shop.

Knock down Roubo bench as originally built.

The first design improvement was to add a wood screw from Acer-Ferrous, a product we sell here on our web site.  This makes it easy for interested parties to actually try out these beautiful screws, and see how well they operate.  The one installed has a walnut hub to match the walnut chop.  Also, the Benchcrafted criss-cross  was added to keep the vice jaw parallel, and make the screw operate more smoothly.  The criss-cross supports the weight of the chop, so there is no binding on the screw.  Because of this addition, a new thicker chop had to be made to accommodate the deep mortise that the criss-cross retracts into.  Fortunately the leg of the bench was big enough for both the criss-cross and the large hole needed to accommodate the screw.  The Acer-Ferrous brass garter was also added to the face of the chop mounted at a 45 degree angle.  The garters function is to attach the chop to the screw so they move in tandem when opening the vice.

New leg vice with Benchcrafted criss-cross and Acer-Ferrous wood screw.

Also added was a shelf, which will be much appreciated during shows to store tools for quick retrieval.  It will help keep the bench top from becoming cluttered during demonstrations.  It was constructed from a single piece of walnut, and simply lays in place atop the cleats on the ends of the long stretchers.  Very quick to set in place.

Shelf set in place.

Another detail was the toothed planing stop from Black Bear Forge.  This will add a traditional work holding technique from the past, and will be welcome during woodworking demonstrations and woodworking classes.  It is a quick and simple way to secure a work piece for hand planing.  The vice jaws were lined with a product from Benchcrafted called crubber.    It is a gasket material made from natural rubber and cork, and looks to be a good method of adding grip and a measure of protection to the work piece being held in the vice.

Planing stop from Black Bear Forge, and jaws lined with crubber from Benchcrafted.

All in all, this looks to be a positive improvement to our show bench.  Be sure to check it out when seeing us at woodworking shows!

Finished bench.

Roubo Bench Project

After reading about workbench designs from the past on Chris Schwarz’s blog, I purchased both books on benches that he wrote;  “Workbenches  from Design & Theory to Construction & Use” and “The Workbench Design Book”  Both offered a lot of good insight as to what makes a bench work well for the user.  Armed with that information, I set out to build a no compromise bench, based on the design of Andre Roubo, an eighteenth century French cabinetmaker. First, I had to find thick, wide wood.  , Hollister’s Sawmill, located in Columbia, PA, had some beautiful 4″ thick ash that was just what I needed.   The entire bench, except the shelf was built from three pieces of wood.

Roubo-Bench-1

  The top center board measured 18″ wide, to which a strip was added on each side, allowing the mortises for the legs and the square dog holes to be easily cut in.  Because of the size of the top, it needed to be worked with hand tools.  The edges were dressed first, and the side strips were glued on.  The end cap was fit and fastened in place with Spax brand lag screws, after which the bottom surface was flattened by hand.

Once the top was together, the 4″ x 6″ legs were made with a mortise and sliding dovetail going through the top.  Not only is this joint strong, but it has a pleasing look too.

Roubo-Bench-5

Installing and fitting the vice hardware was done before the legs were fastened in place.  I chose Benchcrafted hardware, a very high quality product made in the US.  I am quite pleased with the smooth operation of both the tail and leg vice, and the thorough instructions for installation.

Note that the legs have a live edge on the inside corners.  I wanted to use as much wood as possible from the plank, so left it as cut. The vice chop, and also the sliding dead man, are walnut.

At this point, the stretchers were made with draw bored mortise and tenon joints, and the bench was assembled.  I had help with this process, as there was a lot to do in a short amount of time.  Plus, it was heavy!

After glue up, the top was flattened with hand planes, a straight edge, and winding sticks.  This took a couple of sessions to complete, as there was some twist in the top and a fair amount of material had to be removed from the high spots.

I added a shelf and sliding dead man plus made a dog for every hole. The finish is  two coats of Danish oil.  Overall length is 84″ (the maximum I could get out of the wood), and 23″ deep.  Total weight is 370 pounds.  Very sturdy indeed.  I hope to soon add hold fast holes to the top.

So far, I am very pleased with how the bench works for me.  Having a solid work surface and vices that grip securely and smoothly are a big help and make hand tool woodworking much more efficient and pleasurable.