Practicalities of Slabbing

[BobL]

Folks, how do you decide what thickness to mill slabs ?

Up until the BIL mill all of the stuff I was milling was smallish diameter (<18") and short (<5 ft) so physical handling of the slabs was not an issue. With BIL and the latest logs I'm tackling, sheer physical handling has suddenly become an issue with some of the thicker (3"+) slabs which are starting to get up around 400lbs. The reason I am doing these so thick is that hopefully this will reduced distortion and checking while drying.

When milling in the open air I am fortunate to have access to a fork lift but the thought of then manouvring these heavyweight inside a narrow drying shed and then later handling these for resawing has made me think a lot more about the size of these slabs.

I realize this is a bit like asking "how long is a piece of string?" but I am still interested in how you decide on what thicknesses to mill.

Cheers

 

[OZDOG]

All you you have to do to lift big slabs is make sure ya eat ya weet-bix! Just kidding. I have the same troubles about how thick to go because I don't have any moving machinery either. I've cut a few thick slabs just ignoring the fact that they are going to be bloody heavy to move.
I've cut slabs two inches thick and they've dried fine then milled the same type of tree, same species, same thickness and they've split and warped etc. I think sometimes it depends on the tension in the trees, for eg, if they've been wind-blown all their lives or growing at an angle. If I'm getting logs from an arborist I ask them what environment they've come from, and if they have more tension I tend to cut those ones thicker to give them a better chance to dry well.
I could be totally wrong with this. This is just based on my experience. It seems to be working for me though.
lets hope we get more answers on this!

 

[carvinmark]

I cut most everything either 2", 2,1/2" or 3" unless I'm cutting a mantel. I feel for you guys without equipment to handle the slabs. I used to do it all by hand too, now I have a loader and it sure makes life better.

 

[woodshop]

Depends on what I plan on using the wood for in the woodshop. I rarely mill anything over 8/4 (2 inches) because 1) as you say they can get REAL heavy and difficult to move around. 2) except for maybe a special or unique piece, I rarely have a need for wood that thick. 3) it takes forever to dry through and through. Also, as was said in a recent post, trying to air dry anything more than 3" thick is difficult to do without at least some cracking or splitting. Simply the nature of how wood loses moisture and dries. (now if you have a kiln and can spend lots of time in it, $$$$$, another story). So, unless I'm planning on making a thick mantle, or one of those rustic slab coffee tables, I find very few uses for anything that thick. I guess if you had a business that sells rustic tables... OK, but most of us just don't need that many huge thick slabs unless we plan on selling them maybe.

Of course this is from my (narrow?) perspective. I have a small business on the side selling things from my shop. I sticker and air dry a few thousand bd ft a year. I don't use that much wood at the moment, but am "banking" it for when I retire and do the woodworking full time. I use mostly 3/4 lumber, but also need 4/4 for things like breadboards, 5/4 and 6/4 for table legs, and for one of my items (nutcracker) I need lots of 7/4. Others here obviously might have different needs. My rule of thumb which has worked well is to mill wet wood 1/4 inch more than I want the finished thickness to be. This takes care of the shrinkage that occurs as the wood loses moisture, as well as allows for the slight twisting or cupping that occurs also. This is a general rule... for stuff like apple that twists up like a pretzel no matter what you do or how you dry it, I mill thicker and allow for more waste. Thus, since I use mostly 3/4 lumber, I mill most of my stuff 1 1/8 inch. Any thinner, unless it's top grade pure quartersawn, the boards tend to warp and twist too much air drying, even when weighted down. So for 7/4 (1 3/4 inch) I will mill 8/4 (2 inches)... etc etc.

 

[aggiewoodbutchr]

If I intend to resaw, rip and/or edge it further into finished stock, I don't like to go any thicker than 8/4. That's about the thickest I can yield an acceptable amount of top grade material.

For slabs I intend to use in their natural form, I have learned that the wider the slab is, the thicker it needs to be. I have lost as much as an inch of thickness on slabs over 36" wide when flattening them. It's really hard to accurately predict how a slab will behave when it dries but experience in handling them from start to finish will teach you a lot. I'm getting better at "reading" them compared to when I started but I still have MUCH to learn.

 

[dustytools]

Much like Woodshop I tend to mill wood with particular projects in mind. I have some white oak that I milled 2" thick which will end up at about 1 3/4 inches round after its turned to final size. Most everything else I have milled at 1" which will be planed down to 3/4" for various other projects. I did however make the mistake of trying to air dry some white oak in 2"x2"X6' pieces when I should have left them full width until they were dried and then ripped them to final width as some of them are starting to twist up on me.

 

[Sawyer Rob]

Depends on what I plan on using the wood for in the woodshop. I rarely mill anything over 8/4 (2 inches) because 1) as you say they can get REAL heavy and difficult to move around. 2) except for maybe a special or unique piece, I rarely have a need for wood that thick. 3) it takes forever to dry through and through. Also, as was said in a recent post, trying to air dry anything more than 3" thick is difficult to do without at least some cracking or splitting. Simply the nature of how wood loses moisture and dries. (now if you have a kiln and can spend lots of time in it, $$$$$, another story). So, unless I'm planning on making a thick mantle, or one of those rustic slab coffee tables, I find very few uses for anything that thick.

That's exactly the same with me.... By far the most used thickness is 5/4, and if your going to sell rough lumber, that's what buyers will want the most of. It's also what i personally use the most of.

Rob

 

[BobL]

Thanks Guys - it is very interesting to hear what you do.

Although I don't have an immediate use for any of the slabs/timber I'm cutting I hope the speed of drying can be addressed somewhat by our proposed drying shed.

 

[woodshop]

Thanks Guys - it is very interesting to hear what you do.

Although I don't have an immediate use for any of the slabs/timber I'm cutting I hope the speed of drying can be addressed somewhat by our proposed drying shed.

Just remember that for thicker stuff, say 2 inches or more, you don't want it to dry too fast, as the outside of the plank dries, but inside doesn't, and you get some serious internal stresses that even when the wood does eventually dry through and through, still show up later when you work it in the shop. Drying thick planks too fast is also what causes those huge cracks that can go an inch or more deep into your wood.