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Brian D Smith
05-25-2017, 1:09 PM
just in the works of having some walnut and cherry slabbed up. i think i'm going to, for the most part, get them cut between 8/4 and 12/4. i don't want to sound misinformed but i'm now a sawyer and i have never had lumber cut for me. so i want to be able to tell the guy exactly what i want.

when slabbing logs do you cut slabs until you get right above the pitch, then cut the next slab to include the pith and just cut this board into 2 pieces removing the center?

may sound like a dumb question but i'll own that haha

thanks!

Bob Bouis
05-25-2017, 2:00 PM
There's not really any right or wrong way to do it unless you're planning to sell the lumber to a wholesaler or something.

It really depends on the particular log, how level the pith is, and so forth and so on. What you'd prefer to do get as many pieces that won't be impacted by it as possible. That could be one 12/4 piece with the pith centered, two 8/4 slabs with the pith right between them, etc.

Watch out for ring shake and heart checks on cherry and walnut. That'll usually decide how you cut them.

Brian D Smith
05-25-2017, 2:10 PM
thanks Bob. i'm sure the guy sawing will know as well i just want to be prepared in case he asks....i don't want to make a mistake and have useless lumber after a year or two. and I may sell some down the road when i run out of things to build, but for now it's all staying with me!

Izzy Camire
05-25-2017, 3:56 PM
Brian, I have a mill and the response from Bob is a good one. It depends on your log and how the pith winds through your log. You also have to consider tension in the log which means sometimes you take a cut on one side and then flip the log over to cut on the opposite side to relieve tension there too. Just tell your sawyer what you are looking for and he should know what questions to ask and how to go about getting you the best boards you can.
You also mention slabbing but you might want to consider taking a waste slab cut on all 4 sides. I like to open a 4" face on the 4 sides and go from here at least then you have a flat edge on some of your boards.

Brian D Smith
05-25-2017, 7:35 PM
Izzy, thank you for the advice. I wanted some live edge slabs so that is why I mentioned slabbing. The rest will be cut into boards.

I'm not sure I'm sold on the whole live edge thing yet but want to have some on hand so I can take the leap if I want.

Danny Hamsley
05-31-2017, 7:55 AM
The pith in walnut behaves well, so I go for the best yield and widest slabs in walnut and center the pith in the center slab. The pith in cherry behaves awful and will crack the slab for several inches on each side to the point that the slab is compromised unless you cut out the cracked center. Therefore, on cherry, I will avoid leaving any of the juvenile wood and pith in any of the slabs or boards.

Prashun Patel
05-31-2017, 8:36 AM
"...do you cut slabs until you get right above the pith, then cut the next slab to include the pith and just cut this board into 2 pieces removing the center?"

I can't speak for professional sawyers, but on the chainsawed logs I harvest for bowl blanks, this is exactly what I do. The two resultant boards that you'll get on either side of the pith will be quartersawn and quite stable.

I will offer this unsolicited:

I underestimated just how much lumber was produced when I had a beech and oak tree harvested. If I could do it again, I would have simply had the boards milled into 8/4, or 10/4 rift or quartersawn boards. It would have cost more, but would have resulted in better, more stable, more usable lumber for me. The live-edge slabs I ended up with were unremarkable and heavy. Despite having a pallet full of live-edge slabs, when I have a slab project, I end up buying new ones from dealers because the aesthetic or size is so critical.

QS/riftsawn in cherry and walnut is conversely harder to find but easier to make.

Scott T Smith
06-02-2017, 4:55 PM
Brian, like Danny I am a sawyer and kiln operator and I concur with his advice about walnut (we don't mill much cherry so I don't have anything to offer there).

Typically when setting up to slab we will center the pith as best as possible, and capture it in the center slab. If the pith splits are extensive after drying, we have the choice of either cutting a 6" or so piece out of the center of the slab and then gluing the outer pieces together, or simply filling in the checks with black epoxy.

Each log has it's own story to tell, and with all logs destined for slabbing we will study the log to determine how best to set it up to yield the most storied lumber. Sometimes that means milling parallel to a face instead of parallel to the pith, other times it doesn't. With black walnut we are always looking to understand where the best crotch figure can be obtained and will determine our opening faces accordingly.

How wide are your logs? On wider logs (36"+) we will frequently mill them extra thick in order to allow room to S2S the slabs after wood movement and distortion. Thus, a 48" wide BW log may be slabbed at 3-1/4", allowing room for the slabs to shrink down to 2-3/4 - 2-7/8 after drying, and then 3/4" for s2s or S1S with a skip face joint on the bottom side.

Tom Hogard
06-05-2017, 9:47 PM
Brian,

Just as Scott and Danny said, I also try to center the pith in a plank; figuring that if it behaves badly, it's only one plank. I often mill for a series of bookmatched planks - a sequence of 6 planks yields 5 potential pairs (including the one with the pith). Ideally, that would be 3 pairs but sometimes it is two pairs and two orphans (shelves or bar tops?) - all depends on the quality of the matches, and who is evaluating them.

I illustrated this topic in a video I did last summer, https://youtu.be/uhJnuWPLfKk , check out around 11:30 in the video.