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Tim McEneany
06-27-2010, 9:07 PM
I was browsing around a local lumber yard this weekend and found that they carry 4x6 and 6x6 fir timbers in 16' lengths. Since I was planing to build a Roubo bench the neander way, I thought the 6x6 timbers would work great for the top and legs (much less to laminate than with 2x stock). Does this sound like a good idea? Are there any gotchas I need to look out for when using timbers? Also the timbers have a slight red hue to them, which I thought was a sign that they were treated, but I was told that they were not treated. Is that true? I certainly don't want to use treated lumber for a bench.

Rick Rutten
06-27-2010, 9:32 PM
Most of the Doug Fir I have in the garage has a slight pinkish hue to it. It is really noticeable next to the pine. In log homes when Douglas Fir logs are refered to it is not unusual to metion the pinkish tinge. Even today the pressure treated stuff at the Borg is still green.

Rick

Michael Peet
06-27-2010, 10:11 PM
If you're doing it by hand, my 2¢ is that the bigger boards will save you some planing.

Mike

Dan Karachio
06-27-2010, 10:29 PM
I've never used them for a top, but I have had major shrinkage with Lowes fir 4x4. They can be kind of wet, so please keep that in mind. However, isn't it in part of Schwartz's book that he used almost dropping wet lumber in his bench? I think he referred to some advantage. I could reach over 4 feet and grab the book, but it's late and I am tired and useless!

Jim Knishka
06-28-2010, 12:51 AM
A year or so ago I bought 12x12 and 8x10 beams from a 160 year old feed mill that was torn down. I was very excited and saw these as my ticket to a roubo. Then I realized that the sawyers had off course sliced many boards off those old growth timbers and I was left with the center of the trunk... I think I'm still going to be able to pull it off but my dream of 12 inch wide pieces to work with for the top is gone! Anyway, the pith probably doesn't matter for the legs but I'd hesitate using them for the top.

Michael Peet
06-28-2010, 7:27 AM
isn't it in part of Schwartz's book that he used almost dropping wet lumber in his bench? I think he referred to some advantage.

Yes, his assertion is that as the top dries and shrinks, it pulls the tops of the legs along with it. This results in the legs being canted outward at the bottom ever so slightly, aiding in stability.

Mike

Mike Olson
06-28-2010, 9:00 AM
most 4x4 and 6x6's are cut from the dead center of the tree. This makes them the most unstable of all the wood, you should never by wood that has the Pith in it. If you can find some that is not from the center it should be fine.

Terry Beadle
06-28-2010, 9:13 AM
When I built my work bench 8 years ago, I used some 4 X 6 pine from Home Depot. I bought it in two 16' pieces. I have experienced no problems including twist or shrinkage. Maybe luck but I'd rather think big timber is a bonus. The mortice/tennon joints are anchored together with bolts and I give them a slight twist each year ( when I can remember ) but they have shown very little need.

Certainly when you pick your stock be sure to look at the end grain and go for as far away as possible from the center portion. My theory is that because in the South there are so many big pines, it's not as hard to get non-core timber.

That being said, IMO I still think laminations of 8 qtr stock are stronger and more predictable than big timber and can make the morticeing an easier affair.

Good Luck and enjoy the process !

Michael Peet
06-28-2010, 9:52 AM
If you read Chris Schwarz's blog, his latest Roubo is made with two gigantic cherry slabs for the top. I don't know if I'm allowed to post a link, but if you google it it should be easy to find.

Mike

Tim McEneany
06-28-2010, 10:22 AM
Thanks for all the helpful comments and advice. There was a mix of boards with and without the pith, and a few looked quite clear. I don't have a moisture meter but could tell that they were somewhat wet. I will probably have to cut them to rough size and let them dry in my garage for awhile.


If you read Chris Schwarz's blog, his latest Roubo is made with two gigantic cherry slabs for the top.

I actually just ordered Schwarz's new workbench DVD and can't wait to check it out.

Izzy Camire
06-28-2010, 2:46 PM
Mike Olson is correct. I do some sawmilling and when I make 4x4s I use small diameter logs and box the heart. This makes a post with less twisting and movement. It is ideal for post but not for other purposes.

Roger Benton
06-29-2010, 9:27 AM
Yes, his assertion is that as the top dries and shrinks, it pulls the tops of the legs along with it. This results in the legs being canted outward at the bottom ever so slightly, aiding in stability.

Mike

concerning using wood with a high moisture content in the bench, schwarz also suggests using wet wood for legs and drier wood for stretchers, as the mortises in the wet wood will shrink around the dry tenons and become tighter over time.

Frank Drew
07-01-2010, 2:38 PM
However, isn't it in part of Schwartz's book that he used almost dropping wet lumber in his bench? I think he referred to some advantage.


Yes, his assertion is that as the top dries and shrinks, it pulls the tops of the legs along with it. This results in the legs being canted outward at the bottom ever so slightly, aiding in stability.

Mike

I must be missing something here; how does he know that the top will shrink evenly, pulling all four corners just the same amount? And as the top shrinks, isn't it also prone to warping? How do you do accurate woodworking on a workbench top that isn't flat?

Why not start with suitably dry, stable material and build in any features you want, such as canted legs?

Matt Radtke
07-01-2010, 2:45 PM
I must be missing something here; how does he know that the top will shrink evenly, pulling all four corners just the same amount? And as the top shrinks, isn't it also prone to warping? How do you do accurate woodworking on a workbench top that isn't flat?

Why not start with suitably dry, stable material and build in any features you want, such as canted legs?

He doesn't. The recommendation is to use the driest wood for the top, limiting the potential for warping. Any warping will be dealt with regular flattening of the top, which is required anway.

Frank Drew
07-01-2010, 3:11 PM
So what about that business with the legs canting as the top dries and shrinks, and how that's a good thing since it would increase stability?

(But if that occurs, wouldn't you have to recut the bottom of the legs, so that they sit firmly on the floor?)

As I said, there's probably something I'm missing -- I didn't read the blog entry cited, just what was mentioned here about it.

Michael Peet
07-01-2010, 7:09 PM
He doesn't. The recommendation is to use the driest wood for the top, limiting the potential for warping. Any warping will be dealt with regular flattening of the top, which is required anway.

He actually does. From from the Workbenches book:

"Choose the wettest boards for the top and legs, those parts will shrink on the stretchers of the bench, which should have a lower moisture content than the other parts. This approach will keep the joints tight and will slightly distort the base's shape, which is going to happen anyway."

I only happened to have the book right next to me, as I have been constantly referring to it as I make my own feeble attempt at a Roubo ;). I am pretty sure he elaborates on this further elsewhere in the book, but I can't find it right now.

Cheers,

Mike

Frank Drew
07-02-2010, 8:24 PM
"Choose the wettest boards for the top and legs...This approach will keep the joints tight and will slightly distort the base's shape, which is going to happen anyway."


:confused:

Matt Radtke
07-02-2010, 8:41 PM
I stand corrected. Though it's not terribly surprising. The true, 14+' original french benches were 4-6" thick slabs. And often green. The Roubo from Landis' book mentions something to that effect.

Frank, I think you're getting hung up on the wet wood. I believe from Landis and Schwarz both mention a slight bit a-framing happening. Just about enough to make the dovetail M&T tight. To me that says over the length of the legs, ~34", they are getting pulled in about a 1/16th or so. Not enough to drastically alter the feet.

Frank Drew
07-03-2010, 1:34 AM
Matt,

When you say I'm getting "hung up" on the wet wood, that makes it sound like I'm the one with the problem, a proposition I, not surprisingly, reject. I understand the idea of using a combination of green and dry wood in some structures -- Shaker chairs, for example -- but work benches aren't chairs, in use they need to be straight and flat and stable, so the idea of making one out of unseasoned wood strikes me as odd (not to say wrongheaded.)

What does Mr. Schwarz mean by saying that the base's shape is going to get distorted anyway? Anyway what? Using seasoned material, and cutting your joints accurately, the base, and top, should stay pretty much as made, at least in my experience.

Are people romanticizing the act of making a Roubo bench, and in the process perhaps forgetting what a woodworking bench is to be used for?

Just asking...

Frank Drew
07-03-2010, 8:57 PM
Matt,

I didn't know what you meant by dovetail mortise and tenon, but I just watched the video and see exactly what you mean; it's like a bridle joint with the outer tenon dovetailed.

His bench looks a bit short for his height, although I know that everyone has his or her particular method of working (it would kill me to have to stoop over like that to work.)