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View Full Version : Making a roubo... Recommendations?



Bram de Jong
12-02-2019, 4:31 PM
Hi Neanders,

About 6 months back I bought a bunch of Beech boards straight from a sawmill. They are 4cm (~2.5 inch) thick, about 40cm (~16 inch) wide and about 2m long (~79 inch). As I want to be Neander, but perhaps not go all the way I have access to a workshop on Thursday to do all the rip cuts. My plan is to laminate the top to be 10cm (~4 inch) thick, that means approx 16 full length rips. I bought a brand new rip saw that is 300mm (~11 inch) in diameter.

The legs I will laminate to be 12x12 (4.7 x 4.7) with tenons a la Schwartz. The table would be 2m long of course, I plan to overhang the sides 30cm (~12 inch) left and right of the legs. For the stretchers I will try to see if the shop has a bandsaw to resaw a few of the strips to 2cm thick (~3/4) as otherwise the stretchers would be terribly fat!

I have some very old hardware from a half-rotten bench that was kept in the family from which I can take a leg vise, at least the metal parts. I have a single piece of V-shaped ash I want to use for the leg vise.

Armed with the Swartz book I will go into "omg so many errors, but I made my bench" land, but before I do that here's some questions:

I've been reading about rip cutting and many people say you should plane before you rip, but only having the shop for one day (approx 6 hours) I'm not sure this can work out - there's quite some cutting to do! So, my plan was to rip a bit wider than needed to account for any dramatic bowing... Would that be just fine?
I've seen a bunch of tutorials on table saw safety because this is also going to be my first time using one of these beasts. It scares me quite a bit, especially as I try to stay away from electric things for all my woodworking. Any tips for a newbie on doing all these rips?
As I'm a glutton for punishment I want to hand-plane all the pieces, actually mostly to learn... I was wondering if you guys have any tips on hand-planing these long rips (4" x 79" x 2.5"). How "flat" do these really have to be to laminate them?
I know I should try to put them all strips in the same grain direction and try to put the curve of the rings in opposition ( so like... )()()()()() ), but are there any additional ideas for keeping the top stable and as flat as possible for flattening later?
The wood was air-dried and I think it has some moisture from being in a (relatively dry) cellar for a few months, this comes with two challenges: beetles (ARGH!) and the fact that the wood might bend again when it dries out further when I bring it into my home. Any hints regarding these two topics?


Here's a picture - ash slab on top, you can see the marks of the beetles in the chunks where the bark fell off. Also gives you an idea about the "straightness" of these slabs. Definitely not perfect, but not too bad either!

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Any help or advice is INCREDIBLY welcome!

Bram

Scott Winners
12-02-2019, 4:59 PM
If you made your top 8 inches thick how wide would it be? Just asking. With beech 4" thick and two meters long is likely very satisfactory, but I am not investing this kind of time into benches that weigh less than 300# ever again.

Bram de Jong
12-02-2019, 5:04 PM
I'd have to make it half as long, so... 40", the amount of wood is.... Limited....

Bram de Jong
12-02-2019, 5:06 PM
I.e. the weight would be the same! :-)

Warren Mickley
12-02-2019, 6:14 PM
I recommend you follow the Roubo method rather than the Schwarz method. Roubo would have been amused at someone trying to glue all these strips together.

Roubo recommends a single plank for the top, 5 or 6 inches thick, 20 to 22 inches wide, and 6 to 12 feet long. I would not go less than 4x20x75. Roubo recommends orienting the plank with the bark side down. This is many times easier than Schwarz method. A lot less sawing and planing. You can make this with green timber.

For the legs you want 4x4 or 5x5 timbers. You cab use old salvage timbers if you want. The stretchers should be slightly thinner than the legs, like 3x6 or 2 1/2 x5.

Andrew Seemann
12-02-2019, 9:03 PM
I recommend you follow the Roubo method rather than the Schwarz method. Roubo would have been amused at someone trying to glue all these strips together.

Roubo recommends a single plank for the top, 5 or 6 inches thick, 20 to 22 inches wide, and 6 to 12 feet long. I would not go less than 4x20x75. Roubo recommends orienting the plank with the bark side down. This is many times easier than Schwarz method. A lot less sawing and planing. You can make this with green timber.

For the legs you want 4x4 or 5x5 timbers. You cab use old salvage timbers if you want. The stretchers should be slightly thinner than the legs, like 3x6 or 2 1/2 x5.

Laminations might help in the extremes of the North American continent. Roubo's original design seems like it worked just fine in the much milder climate of France (and Germany :) )

Just to be clear though, there is no disgrace or shame in using power tools. Many woodworkers get into hand tool woodworking for romantic reasons, but there is nothing romantic about a broken back or ending the day so sore you can barely move (and some of us are at the age where that damage can be permanent). Had there been a planing mill down Roubo's street, he most certainly would have been a regular customer.

And while we are on the subject of power tools, 4 cm Beech is not the wood to use the first time you try using a table saw. My tip would be either have someone who knows what they are doing rip them for you, or at very minimum have someone who knows what they are doing show you how to use the saw and then practice on some 2 cm scrap.

Videos are no substitute for in person instruction on a machine that can eat a finger in a microsecond, or send a board through a wall. Also note that though European Beech isn't nearly as unstable as American beech (which tends dry into airplane propellers and boat sides) is still can have internal tensions, which will be worse the thicker it is. This can be dangerous while ripping if the board "relaxes" into the blade.

Derek Cohen
12-03-2019, 12:59 AM
The question is whether Roubo would build the same way today if he had modern machinery? Would he use a pit saw because that was the way it was done in his day, or would he avail himself of a horizontal bandsaw? I can see the time saving in using a slab over laminations, as well as choosing green wood over dry wood in a slab - but if machines could do the rough work in his day, would he have preferred the more stable lamination if he had the choice?

This is all quite academic since I assume that most, like myself, cannot stuff a tree in the back of your car or pickup ("ute" in oz-speak). So I purchased rough-sawn 4 x 2" European Oak boards and laminated them into a 22" wide, 3 1/2" thick and 75" long bench top. With rectangular dog holes. The undercarraige is recycled Jarrah, and the whole deal is a dry 350- - 400 lb (measured by my wife hoisting it on a shoulder while standing on the bathroom scale. It may not be the real thing, but I suspect that Roubo would not laugh at it.

https://i.postimg.cc/NffdYGd3/D4a.jpg

Regards from Perth

Derek

Warren Mickley
12-03-2019, 7:38 AM
I think Roubo would laugh to see such sport. Cutting up a piece of timber just to glue it back up again.

Where in the world did you get the idea that laminations were more stable? Surely not from experience.

Here is a picture of one of the Dominy benches. It is 5 1/2 inches thick. It was used by seven generations of the Dominy family on Long Island. That is part of the North American continent mentioned by Andrew. This picture was taken by Chris Schwarz. The current Winterthur curator assured me in January that the fake shaving horse would be removed from this recreation of the shop.
.420789

Here in Pennsylvania, Daniel O'Hagan's thick slab bench is still in good shape after forty some years, and I suspect that Rob Tarule's solid slab Roubo bench is still in good shape in Vermont after close to forty years.

Michael Bulatowicz
12-03-2019, 7:41 AM
Please take my advice with a grain of salt, as I have nowhere near the level of experience and expertise of someone like Warren or Derek.

To answer your question about additional ideas for keeping a laminated top stable, notice on the right hand side of Derek’s picture that he has a breadboard end (with beautiful dovetails, I might add) oriented with its long grain across the end grain of the laminated top. A breadboard end like this on each end of the top will help keep the top flat. Further, not being familiar with the Roubo design for what is immediately beneath the top I would suggest a stretcher/bearer at each pair of legs (already present in the design?) that is again oriented the same way as the breadboard end. These cross-grain oriented boards will help constrain the top against cupping and, to a lesser extent, against twisting. You will need to make sure to accommodate wood movement in the attachment of these components, such as is typical of breadboard mortise and tenon design, for example.

Best regards,

Michael Bulatowicz

Phil Mueller
12-03-2019, 8:19 AM
Build the bench per the Schwarz book and you’ll be fine. The one thing you may want to do is leave a bit more overhang, if possible, to allow for an end vise/tail vise if you choose to add one some day.

I agree with the table saw mentoring suggestion. Your rough edge boards are going to add to the challenge. Not to mention that your lumber surely has some twist/bow/cupping that should be dealt with before running it through a table saw. Get someone who can help you mill up the boards.

Derek Cohen
12-03-2019, 8:23 AM
I think Roubo would laugh to see such sport. Cutting up a piece of timber just to glue it back up again.

Where in the world did you get the idea that laminations were more stable? Surely not from experience.

Here is a picture of one of the Dominy benches. It is 5 1/2 inches thick. It was used by seven generations of the Dominy family on Long Island. That is part of the North American continent mentioned by Andrew. This picture was taken by Chris Schwarz. The current Winterthur curator assured me in January that the fake shaving horse would be removed from this recreation of the shop.
.420789

Here in Pennsylvania, Daniel O'Hagan's thick slab bench is still in good shape after forty some years, and I suspect that Rob Tarule's solid slab Roubo bench is still in good shape in Vermont after close to forty years.

Warren, you will need to provide evidence that solid wood - especially green solid wood - is more stable than laminations of dry wood.

I can name several reasons why laminations are going to end up more stable:

The weakness in solid wood is in its very nature - grain is a weak point where timber may split. Laminations disrupt the grain and splitting, and the glue adds both flexibility and strength.

By contrast, a solid wide and thick green board is vulnerable to checking and splitting.

Nevertheless, I think that you missed the point I made in my earlier post - that Roubo constructed for his era. It was the more efficient way to go. But would he do this today, when it is possible to construct in a way he could not do efficiently.

Regards from Perth

Derek

Robert Hazelwood
12-03-2019, 8:25 AM
I've been reading about rip cutting and many people say you should plane before you rip, but only having the shop for one day (approx 6 hours) I'm not sure this can work out - there's quite some cutting to do! So, my plan was to rip a bit wider than needed to account for any dramatic bowing... Would that be just fine



Yes, absolutely rip cut before you plane. It's easier to plane smaller pieces flat to begin with, and they are bound to move after you rip them.





I've seen a bunch of tutorials on table saw safety because this is also going to be my first time using one of these beasts. It scares me quite a bit, especially as I try to stay away from electric things for all my woodworking. Any tips for a newbie on doing all these rips?



Does the shop have a bandsaw? I'd rather rip rough lumber like this on a bandsaw. I don't like to put anything through the tablesaw that isn't milled flat and square. It's different if they have a sliding tablesaw with enough table travel to rip the entire length- then you can just clamp the pieces to the sliding table.

That said, people do rip rough lumber on a regular tablesaw and most of the time they get away with it. Just keep your hands from getting beyond the blade, and stand a bit to the side of the likely kickback path. And make sure the saw has a splitter or riving knife.






As I'm a glutton for punishment I want to hand-plane all the pieces, actually mostly to learn... I was wondering if you guys have any tips on hand-planing these long rips (4" x 79" x 2.5"). How "flat" do these really have to be to laminate them?



At 2.5" thick they will have to be pretty flat, I'm afraid. The more flexible the laminates are, the more bow you can tolerate. To test your fit before glue up, you can take half of the top laminates and clamp them together like you are doing the glue up. IF you can close all of the seams tightly without insane clamping pressure then you are good to go. If there are any gaps. If there are, mark the high spots where the boards touch between the gaps and plane those a bit, then test again.

The upside to having thick laminates is you don't have to plane as many of them. But you will have to plane to a tighter tolerance.

If you want to learn hand planing this should do it! Try not to burn yourself out though, this a serious amount of work in a hard wood.







I know I should try to put them all strips in the same grain direction and try to put the curve of the rings in opposition ( so like... )()()()()() ), but are there any additional ideas for keeping the top stable and as flat as possible for flattening later?
The wood was air-dried and I think it has some moisture from being in a (relatively dry) cellar for a few months, this comes with two challenges: beetles (ARGH!) and the fact that the wood might bend again when it dries out further when I bring it into my home. Any hints regarding these two topics?




I think you have the right idea on the strips, though if you have to deviate from the textbook perfect grain orientation I wouldn't fret too much. Assuming good glue joints, laminated tops are very stable.

Stack and sticker the boards when you bring them inside, and again for at least a couple days after you have the boards ripped. At 2.5" thick it would take some months (at least) to fully acclimatize to your shop, but for a workbench just do what you can.

ken hatch
12-03-2019, 11:04 AM
If you made your top 8 inches thick how wide would it be? Just asking. With beech 4" thick and two meters long is likely very satisfactory, but I am not investing this kind of time into benches that weigh less than 300# ever again.

Good design can make up for a lot of weight. To turn it around: I'm not investing this kind of time into benches that weight more than 300 lbs and can not be broken down for moving.

ken

Robert Hazelwood
12-03-2019, 12:05 PM
Yeah, my split top Roubo is made from Doug Fir and the top is about 3-1/4" thick, 6.5' long. I estimated the weight at around 250 lbs or so, sans vises. But it is very solid for everything I've done.

I do like being able to move the bench around the shop single handed, in order to create room for an assembly or something. I can lift one side relatively easy and pivot it around to wherever I need it to go. Two guys can get it up on dollies and in a moving truck without too much effort. It does come apart but so far I've moved with it twice and didn't feel the need to break it down.

Eventually I'll have a huge permanent shop hopefully and then I'll build a monster hardwood bench 10' long with a 6" top. For now I'm very happy with this bench.

Bram de Jong
12-03-2019, 12:06 PM
Tbh for me the advantage is that the boards I have and the dimensions of the table I want are not great for using solid one-piece boards. By laminating I can effectively try to optimise the thickness/weight/width of the bench to my liking...

If I went for solid boards I would have to also look at a more complicated design, split-top style.

Bram

Jim Koepke
12-04-2019, 1:35 PM
Bram, Using what you have on hand is a good choice.

If your lumber has edges rough enough to cause problems riding the saw's fence you could attach a piece on top to act as a guide edge. Keep this away from were the blade will be cutting. This will produce a straighter edge for the fence and the piece with the guide will also have a good edge and can be cut along the rough edge to clean it up.

In the day of Roubo, there was a much better availability of large slabs of wood to build a singe piece bench top. There are not many trees left to produce such slabs of that size today. Many of them are either protected by law or the wood is going to be pricey.

Likely the worst that will come of your plan is you will find things you want to try, motivating your desire to build another bench.

One thing to be thankful for is you don't have to do it by hand:

https://sawmillcreek.org/showthread.php?167535

Do to so many other things getting in between me and time in the shop, this project is still on hold and may be abandoned for another method.

jtk

Dan Goodman
12-04-2019, 6:56 PM
I am pretty sure Mr. Schwarz is up to speed on Mr. Roubo's choice of lumber. He seems to have studied up on it a little. I am gonna guess he also is aware of the positives and negatives of a giant slab of oak. I feel like he has advocated both methods and presents them in a manner in which we all pick the best way for us.

Bram de Jong
12-05-2019, 5:32 PM
Well gents, the cutting is done! The table saw was actually very, very impressive, and had a sliding table for putting the wood on. The new ripping blade went through the wood like butter :-)
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Here's all the cut pieces. I was rather lucky to have JUST bought enough boards. Almost nothing was left after my cut-list was done. I have some offcuts, but it was tight:
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Bram

David Eisenhauer
12-05-2019, 6:09 PM
First step done Bram and now you are out of the starting gate. Starting a bench build is the hardest part. Congratulations.

Scott Winners
12-08-2019, 12:13 AM
I have never BBQd with European Beech. A few lumps of American Beech in the charcoal is pretty tasty on beef, nice change of pace from hickory. I think the malt for Rauchbeer is smoked on Euro beech, don't let it those offcuts go to waste.