Lumber question for Moravian workbench

[Tony Wilkins]

As per the other thread I started, I’m trying to decide on a style of bench I can work on (in both senses of the phrase). I’m leaning toward the Moravian, at least at this moment. One question:

The cut list calls for 3 1/2” x 4” legs. In the video they are from ripped larger stock and laminated. Is there any reason I couldn’t use 4x4 stock?

[Jason Lester]

The reason you usually see that is for stability. If you're using something like yellow pine, 4x4's will cup, bow, and twist quite a bit in many cases. If you're using good dry hardwood, it might be ok.

[Tony Wilkins]

The reason you usually see that is for stability. If you're using something like yellow pine, 4x4's will cup, bow, and twist quite a bit in many cases. If you're using good dry hardwood, it might be ok.

Well, looks like I’ll be laminating some boards dag nabbit. If I caught it right, Will Myers said he ripped 2x10’s and laminated them to get the 3.5” by 4 but the math doesn’t seem right unless a lot of planing was done to get them square.

Any other suggestions?

[Stew Denton]

Tony,

A lot of times, 4X4s are cut from the center of the tree, and when that is the case, the lumber will normally develop significant cracks, so lamination, as you mention, is the way to go to avoid that.

Stew

[David Eisenhauer]

Ripping nominal 10" OR 12" wide material to get down to two 3.5" or 4" boards allows you to delete the center pith that can be found in (esp) the construction grade lumber many of us used to build our benches. Also, the wider 2x10's and 2x12's seem to include better looking material than the narrower stuff does. If you do use construction grade material from the Borg, stack/sticker it for air drying for as long as you can stand to step/trip over the pile in your shop as long as possible. But you knew that already, didn't you.

[ken hatch]

Tony,

I’ve done it, made bench base, both ways. Glue up of construction grade SYP and 12/4 hardwood, of the two using 12/4 is easier but can add several hundred dollars to the cost of the base. 12/4 Poplar is easy to find and works well as a workbench base if cost matters.

ken

[ken hatch]

Tony,

Here is a photo of last year’s construction grade bench. The base is made of, IIRC, ripped 2X10 DF.

393037

It worked well and is now my sharpening bench.

The current bench’s base was made using 12/4 Poplar. I haven’t made any photos of it in the “wild” yet but will before this trip is finished. Here are a couple of it in the shop.

393038

393039

In the second photo it is being used for the glue up of a new shop sized Moravian slab. The slab is finished, once home the 12/4 Ash for the base should be at the wood store. The wood vise screw arrived just before we left Tucson. If all goes well (it never does) the new bench should be finished by the end of October.

ken

[ken hatch]

Ripping nominal 10" OR 12" wide material to get down to two 3.5" or 4" boards allows you to delete the center pith that can be found in (esp) the construction grade lumber many of us used to build our benches. Also, the wider 2x10's and 2x12's seem to include better looking material than the narrower stuff does. If you do use construction grade material from the Borg, stack/sticker it for air drying for as long as you can stand to step/trip over the pile in your shop as long as possible. But you knew that already, didn't you.

Tony,

What David said.

ken

[Tony Wilkins]

Ken,
Thanks. In use, have you noticed a difference between the two? Was one of the other much different in cutting the joinery?

[Tony Wilkins]

The other form I’ve looked at extensively is the English/Nicholson bench. All the ones I’m looking at use 4x4 as well for the legs. What is different about them that allows them to use this lumber? Or is there?

[Stew Denton]

Tony,

I don't know about the English bench with 4X4 legs, regarding how the lumber was milled. If it was rift sawn quite a ways from the center of the tree and dried well, then acclimated to the climate well before being squared up and planed to size, then the 4X4s would probably be fairly stable, and splitting would be very unlikely. However, if cut with the center pith up through the 4X4, then significant splitting would be a certainty.

I am sure high quality hardwood will be cut so that it does not have the pith in the 4X4, but the construction grade stuff I use definitely has this problem, of course it costs drastically less than good stuff. Many of the 4X4s in my deck have 1/8" splits running up and down the lumber, but they are construction grade lumber. This is because tangential shrinkage is much greater than radial shrinkage as lumber dries. Thus, because of this difference in shrinkage, if the center off the tree goes up the center of the 4X4, there is absolutely no way it won't split. My understanding is hard woods will split even more than soft wood if the pith goes up the board.

This is a physical property of lumber, and is covered in Hoaleys book "Understanding Wood."

Regards,

Stew

[Tom Bender]

Well, KD hardwood is nicer to work with and looks nice but once the bench is done it doesn't make much difference. If money is tight, spend it on the top and on the vise.

[ken hatch]

Ken,
Thanks. In use, have you noticed tony,

a difference between the two? Was one of the other much different in cutting the joinery?

Tony,

In use no. Both are stable. The build is different, Poplar (12/4) is easier both because of glue up and cutting joinery.

ken

[Tony Wilkins]

I wonder if I were to laminate two 8/4 if it would be easier to cut the leg joinery as two half laps rather than chop the long angled mortise?

[Steven Mikes]

Does using SYP vs poplar or another hardwood make much difference in final bench weight/stability?

[ken hatch]

Does using SYP vs poplar or another hardwood make much difference in final bench weight/stability?

Steven,

Poplar is a light hardwood, there isn’t a lot of difference in base weight between it and SYP. While total weight is an important aspect of stability the design of the base allows a lighter bench to be very strong and stable. Think of triangles vs. squares, the base design is pretty ingenious.

ken

[ken hatch]

BTW, I’m on my Sept. trip to the PNW. In keeping with PNW Fall WX the bench hss been set up for one day so far. It worked welll but no photos of the bench in the wild yet. Maybe later after moving a little south.

ken