Timbers for workbench

[Tim McEneany]

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]

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]

If you're doing it by hand, my 2¢ is that the bigger boards will save you some planing.

Mike

[Dan Karachio]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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.