Workbench: Slabs or boards?

[Rick Prosser]

I am processing some Southern Yellow Pine on the sawmill, and I plan to make a workbench top. Could mill 4x10 slabs or 2x4 boards. Is there a benefit to using 10" wide slabs (maybe 3) instead of the usual glued up 2x4 boards? I have seen some solid slab tops, but never a 2 or 3 piece slab top. Slabs would take longer to dry in the kiln. Maybe 4x4 glue-ups? Suggestions?

[Terry Beadle]

Slabs used to be used a lot back in the day from what I've read. I've seen a few work benches made from slabs ( read wide thick boards ).
The problems with slabs is finding stock that has tight grain ( like old growth ) and stable enough. A slab built table top will need more flattening attention during the year but will be easier to keep flat than side/end grain boards.

Boards can be cut with the grain more vertical than most slab boards are now days IMO. Just look through the typical borg stack of 2 x 4's and see the opportunities as slim pickings. That's whey most folks recommend buying 2 x 12's or 2 x 10's and then ripping your own 2 x 4 table top pieces out of it. There are fewer knots in the larger 2 by stock and you can get more vertical grain opportunities.

IMO a slab board built work table is a definite option. It doesn't take a lot of work to keep it flat. You have a unique opportunity to control the stock you can select from. I'd say take advantage of it and enjoy the ease and strength of a slab topped table. By the way, I'm not trying to imply a board built top is any stronger or weaker than the slab since you can slice 4 inch thick slab boards in your situation. Normally, the board built top would be stronger than a layered slab built top. And...board built tops require more glue, squaring, and truing etc.

You should have a great deal of fun building the work bench you're thinking about. Enjoy it, keep us posted as most folks on SMC are bench freaks ! Hoot!

[Mark Roderick]

Man, if you have the opportunity I would use the slabs just to save all the time flattening and gluing-up the smaller boards. Otherwise, seems six-to-one-half-a-dozen-to-the-other.

[Tom McMahon]

The size of the boards or slabs used to make a bench top is not important. Whats important is the grain pattern of the top when you look at it from the end. It should be as close to quarter sawn as possible, that way it won't cup with seasonal humidity change. It will just get wider and narrower, which means less seasonal flattening. Use the largest pieces you can get to create this pattern.
CoreEndgrain.jpg

[Joe Fabbri]

I have two 10-11" birch slabs that I cut out of a tree myself. I plan use these for my bench top, which should give me 19-20 inches hopefully, when all is said and done. For the thickness, I hope to get 3.5", but it may end up down to 3". I had some problems in splitting the beam, which resulted in a loss of material.

Anyway, I think the slabs will be less work in the glue up. I guess a glue up is not too much trouble if you have a full workbench/workstation to build it on. For me, with nothing but a table saw top or sawhorses to work on (and limited power tools), the less laminations the better. But, I also like the idea of using as much solid wood as possible. You won't have as much quarter sawn grain on top probably, as you can fairly easily get with individual flat/rift sawn boards. But, I think the only real benefit that will give is ease of flattening. If you put the heart side of the slabs up, it should still be a very tough work surface.

In a single slab, Roubo style, construction, with the heart up, the cupping will tighten down on the leg joints. Although for multiple slabs (say three), it might be good to alternate the grain (with the middle slab heart down). For two pieces, though, I think I'd keep the cupping in the same direction, so that the cupping still tightens against the leg joints.

I've seen some two-slab bench tops with the heart apparently down (for instance, I think Schwarz's recent bench has both slabs oriented this way), but this might only have been to avoid major defects on that side of the wood.

[Rick Prosser]

Here is a sample of the log size I have to work with.

BigLog.jpg

[Jim Neeley]

Tom + 1.

I've known a couple of people who had wide flat sawn planks for boards and they swore they'd never do it again. They hated that all of the cupping for a wide expanse occurred in a single direction.

One mostly just "lived with it" and the other re-flattened his bench seasonally.

As for me, laminating boards isn't a big thing, and it's one-time.

[Joe Fabbri]

If you look at antique French style benches, they almost all utilize flat sawn slabs. Maybe they had access to thick slabs that were already very well dried, or they just dealt with it like Jims says.

That said, I'm sure it would be less of a headache to make use of rift/quarterd wood, since you have a mill to work with. If you already planned on three or so slabs, maybe you should consider sawing that log in a 3-4 inch thick cross-shape, and using all of the quartered sections. You will have narrower slabs, but with the best grain.

[Zach Dillinger]

Remember that almost all glue joints, excepting hot hide glue, will have "creep". So, while your carefully selected quartersawn boards might not warp, they will slide around relative to each other. Since the front and back will be supported by the legs, the middle will slide down relative to the other boards, giving you a cupped surface that is no different than you'll get with a slab. I vote slab, since you'll have to flatten your benchtop either way and the non-existent glue joints will not creep.

[Joe Fabbri]

Zach,

What are your thoughts on grain orientation? Am I right to have both of the two slabs cup down toward the legs, rather than alternating the two?

Now, when it comes to three slabs like Rick might be doing, would you alternate the middle board? That wouldn't leave the heart up, but maybe that's not too vital.

Joe

[Sean Richards]

Sounds like you could make a nice split-top bench with 2 slabs- I think that is what I would be doing if I had the choice between 4x10 slabs or 2x4s.

[Rick Prosser]

Remember that almost all glue joints, excepting hot hide glue, will have "creep". ...

I had no idea that the glue joint would creep - after drying. I knew the joints tended to move around when clamping...

Sounds like you could make a nice split-top bench with 2 slabs...

That is a neat idea. I was planning for a solid top - but will consider the split top design with a tool tray/shavings collector in the middle.

rick

[Zahid Naqvi]

Gluing 2x4s and flattening them is not as much work as it is promoted to be. You can easily go the glue ups and flattening in one weekend, if you have enough clamps. Plus it's a one time activity. With 2x4s you will get really nice quartersawn lumber, which will require very little seasonal maintenance, and you can get a hefty 4" top.

With a couple of 12/14" wide boards you will require less upfront work but will need more seasonal maintenance, and chances are you will have to live with a 2-3" inch thick top which will require support under the top to prevent bending under load. If you have a shop like Bob Rozeiski you can probably get away with it (he has a slab top and loves it). My shop is in the garage and I will never do a slab top due to the extreme variations in temperature and humidity my bench has to suffer each year. After a very dry summer and a very wet winter (so far) my borg sourced 4x4 laminated bench top is still quiet flat. Not sure if any slab would have behaved the same.

[Zach Dillinger]

If I were doing a slab top, I'd probably orient it outside-of-the-tree-up. I know that some would say that the wood is harder on the heartwood side, but I have no experience with this. What I would prefer is a top that cups when warping, which sapwood up would do, as that would be easier to plane flat when it becomes necessary to do so. As for gluing two slabs together, I'd probably stick with sapwood up for both planks for the same reason. Planing across the grain to flatten across the width is easier to do with a cupped top.

But I'd be less than overly concerned with the seasonal movement. The bench is going to move, either through glue creep / warping or straight warping. An hour planing a bench every 6 or 12 months isn't a big deal. And you'd have to use that bench a long, long time to plane an inch or more off a 4" thick top to get to 2"... Once the plank settles down (i.e. 4 or 5 years down the road), you'll have only minor distortions to deal with. Again, not a big deal. I'd be doing a slab bench if I had it to do over again. In fact, I might... I've got 3 or 4 4" thick, 10 foot long planks of beech that have been drying for 3 or 4 years. Might make a slab bench at my new house instead of transporting my current 400 pound workbench there.

[whit richardson]

I highly recommed reading Christopher Schwartz's Workbench book before deciding on your bench. I'm on my third or fourth bench and have found what is wanting in standard designs or made for market benches. While I am not a wild fan of any particular Woodworking personailty his book is good in that a) it provides some balanced advice on workbenchs, b) has good plans using SYP and c) provides nice instructions on construction and flattening workbenchs. The French bench is massive but seems fairly straightforward to build. My personal choice is something like the English bench as I am more into furniture repair and refinishing rather than building from scratch.