Slab top for workbench - How to mill it out

[Sean McCurdy]

Hey all, looking for some advice.

In the next few weeks I'm having a larger white oak felled that died last year. At chest height the diameter is 28", and I'm estimate 25' before the first branches.

Assuming that the wood is still good, there is a local guy with a Wood-Mizer with 36" capacity. Since I have the opportunity, I'm considering having the sawyer come out and custom cut some of the lumber into a slab top for a second workbench. My primary bench is a 2'x8' split top Roubo made from reclaimed old growth 2x10 pine laminated to form the top and legs.

I see 2 major options as diagrammed below:
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Option 1:
Estimating I can get a 5x24" slab.
Pros:Largest possible single slab dimension. The QS areas would be fairly stable.
Cons: Contains the pith. My guess is that it'll crack. Heavy as hell to move.

Option 2:
Estimating I can get (2) 5x16-18" slabs. Could theoretically make a 32-36" wide bench that doubles as TS outfeed.
Pros: Does not contain pith. Basically flat sawn lumber, so less likely to crack. Moving each slab easier (but not easy)
Cons: Not a single slab. Higher chance of cupping. Using 2 slabs would be a hell of a big bench, or if only using 1 slab a very narrow one.

I'm leaning towards option 2, as I can then also get some additional QS from the area between them. However, I welcome your inputs.
I am planning on coating the endgrain with anchorseal immediately.

[Andrew Hughes]

They both look good to me.If you do sawn out a QS slab and rip out the pith will you not have a slab as wide as #1?
Seems like you just can't go wrong.
Its nice to have all the wood from the same tree.
Very envious here.:)

[Warren Mickley]

The last thing you want is to have to make a joint between two heavy wet, wide slabs. It is a lot more work than having to move a single heavy slab. The Roubo bench is 22 inches wide; I think you can get that by sawing just off the pith. Maybe even and inch or two off the pith. Roubo says to put the center of the tree up (top of the bench) which gives favorable changes as it dries. Then you can get some quarter sawn boards also.

[David Eisenhauer]

I'm thinking an overhead chainfall hanging from the joists would be required for me to handle either option. At least you have the one bench to use while working on this one. I would take the pith in the center before trying to put two pieces together unless I wanted another split top.

[Chris Fournier]

Option one is not an option! Read up on Bruce Hoadley"s work or take a look at any boxed heart section in a timber frame home. The heart is a problem and so is a heavy white oak timber. Drying defect is a problem.

[Brian Holcombe]

The last thing you want is to have to make a joint between two heavy wet, wide slabs. It is a lot more work than having to move a single heavy slab. The Roubo bench is 22 inches wide; I think you can get that by sawing just off the pith. Maybe even and inch or two off the pith. Roubo says to put the center of the tree up (top of the bench) which gives favorable changes as it dries. Then you can get some quarter sawn boards also.

I agree with Warren, if you can modify your approach a bit then this is far more ideal. One slab 22" wide is a heavy bit of oak, especially wet.

[Sean McCurdy]

Warren, I'll run the math tomorrow on potential slab size, but I like the suggestion. This is why I come here.

Moving stuff of this size makes me glad that my other hobby is weightlifting. Still may need to figure out some handling tricks.

Andrew,
Indeed it will be nice having it all commonly sourced from the same tree. There are plenty of issues living in Illinois, but access to large white oak trees is one upside.

[Todd Stock]

For those that don't get as much time in the weight room: https://www.amazon.com/Moving-Heavy-Things-Jan-Adkins/dp/0937822825

[Noah Magnuson]

Having done slab tops, I would recommend instead taking 4 nice quartersawn slabs about 6-10" or whatever you can get and doing a glue-up. This way you avoid any effects of the heart or cupping associated with asymmetric grain. It will still look fantastic and it is pretty easy to get a seamless joint with hand tools. Just my 2 cents. Yes, it is not the most efficient use of the log, but will make your life much easier.

[William Fretwell]

White oak for an out feed table? Particle board with varnish does a good job. White oak for a work bench would be lovely but it's optimum height will almost certainly not match your table saw. Why compromise a superb bench?
A thick centre slab may not crack if dried properly. My massive poplar slabs (tree was over 4 ft) were quarter sawn and remain crack free except at the very edges. They have been drying for 7 years now, yours will take that long also. Mine don't have the pith of course.
I would try option 1; even if you end up removing the pith you can do it with a chain saw and a few cracks can be filled with epoxy and bronze powder for a very cool look. Dealing with a massive lump of wood on a table saw is almost impossible, a hand circular saw then a hand saw is much easier but the possibility of avoiding all that is worth a try.
Think about the end product, you have 7 years to plan your bench!

[Pete Taran]

+++1 on the quartersawn approach. I don't know if you have ever looked at the 4 x 4s that they stack packs of lumber on, but they are from the center of the tree. They are always checked and cracked, which is what will happen to your top if you include it. Quarter saw that log like a plus sign, discard the pith and resaw the pie shaped pieces that are left into usable lumber of other thicknesses. White Oak is no treat to work with, there is a reason why they used it for sills in old houses!

[Sean McCurdy]

I just wanted to re-visit this thread to update those kind enough to leave suggestions.

Worked with my sawyer to discuss the goals, and largely went with the "+" sign approach to quartersawing the main bits out. Ended up with several timbers that when oriented for the workbench will be 4 1/2" thick and QS, and range from 4-8" wide. Pic of the stack below, it's about half of what we got out of the trunk. To-be workbench timbers in the center.

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[Brian Holcombe]

Very nice!

[Jerry Olexa]

Good looking stock....you did well...

[Stew Denton]

Sean,

Plus 1 on what Jerry and Brian wrote.

I would have given the same advise that Pete gave, and for exactly the same reason. Cut out like your option #1 would certainly have cracks in the center section for the reason that the tangental shrinkage is proportionally greater than the radial shrinkage, and such will absolutely give radial cracking running the length of any section containing the center section and complete growth rings.

It looks like you got great lumber and amazing stuff for a bench. Absolutely congrats. Ya did good!

Stew

[Andrew Hughes]

Yes I like it! I really like working white oak. It makes the whole shop smell great if it had that pile I'd be looking to make a hayrake table for the dining room.
I just don't feel right having a work bench nicer then my dinner table.:)
Enough about me good look stuff you got there.