Sizing lumber

So you stand there in front of the behemoth of a trunk, pondering how to cut the timber into useful lumber. What sizes? How big? Let me give you a few pointers from a furniture and small projects guy.

Bigger is better, right? No! It really is not. Of course it is tempting to slab a huge trunk into full-width slabs. It looks impressive, and there’s that “live edge epoxy river table spalted dining conference table” craze that infest the woodworking wood machinists Youtube channels. From a clickbait perspective, suuure! But from a practical standpoint? Nah.

That being said, a few huge slabs is not a bad thing at all! It’s just that slabs isn’t all there is. Nor live edge siding (villmarkspanel).

Let me point to two earlier articles I wrote on tree slabbin’: a general guide on how to make useful materials out of a tree (cutting, stacking, drying) and the story about a huge oak, determination and fulfilling a dream (which resulted in my big pile of oak planks)

My stack of goodness!

Let’s take a look at the factors you should consider. For in-depth explanations, I refer to the previously mentioned articles – especially “It’s slaburday“.

NOTE! This article is aimed at the production of furniture and woodworking materials, not construction materials. For exterior use and construction, other considerations and "rules" probably applies. I have no knowledge in those areas.

I live in Norway, so this article is aimed at the Scandinavian area. Common measurements and considerations are probably different other places. Adjust accordingly.

Cut types

There are mainly three different “cuts” to choose from. In this image, the bottom half is flat sawn, the L-formation in light brown is quarter sawn and the dark brown in the upper right is rift sawn. The waste is colored differently, and the sap wood is yellowish in color.

  1. Flat sawn (all the boards below center of the image above) means just slicing the tree into slabs without any modifications. This gives you the widest slabs possible, the best yield, very little work, nice cathedral patterns for doors, and material that will cup and twist on you. Expect to loose a lot of thickness when this type of material meets the planer / thicknesser. Cut at least a half inch / 15mm above your target thickness. The wider the board, the thicker it should be. 1” or 25mm is easily converted into chips for smoking fish and meat for wide boards. Lots and lots of smoked nom-noms…!
  2. Quarter sawn (light brown, just 4 planks) means that you cut the log so that each plank (one edge will be live edge, the other sawn – no slabs here) have its annual rings at 60-90 degrees to the surface. True quarter sawn has the rings very close to the 90 degree mark. This gives incredibly nice materials with lots of ray flecking in for example oak. Birch and cherry also show beautiful patterns in quarter sawn material. This cut type gives you lots of work, very stable material, decent yield (you combine it with the last type, rift sawn) and high value materials. You won’t get any wide slabs, and the widest planks will be half the size of the trunk – factor out sapwood here as one will most likely remove the sapwood from these boards since only one side has sapwood / live edge. Add 5 to 10mm to your desired thickness. Resawing is a good option here, so factor in material loss to planing between cuts. Say you have a board at 40mm thickness. You could get three 10mm boards, loosing 10mm to the planer / thicknesser.
  3. Rift sawn (upper right, dark brown boards) means that the annual rings is from 30 to 60 degrees to the surface, with the gold zone being 45 degrees. This gives incredibly stable materials too, with very little to no twist. The materials will have uniform patterns on all sides – perfect for table legs and so on. Combined with quarter sawn, this cut will give you a decent yield. Add sacrifices to the planer gods as you would with quarter sawn.

NOTE: The pith (the center of the log) should be taken out, as the wood WILL split along it. My advice would be to cut one slab with the pith right smack in the middle, then rip that slab into two boards. Now you’ve removed the pith AND you’ve gotten two golden quarter sawn boards – the finest material you can get!

Dictionary for Norwegians:
Quarter sawn: kvartskur, som også dekker "rift sawn". Ta kontakt om du kjenner norsk begrep for rift sawn.
Flat sawn: flaskskur, flatskur, gjennomskjæring
Live edge: bord med 1 eller 2 ukanta sider, typisk for flatskur.
Woodworking kan vel enklest oversettes til sløyd og møbelsnekring, i alle fall i konteksten til denne bloggen.

What are the materials intended for?

You should consider what the materials will be used for. Let’s look at a dining table. Typically, dining tables are around the 2 meter mark, about 80 cm wide. This would require materials no longer than about 210cm (accounting for cracks in the end and possible planer snipe). If we want to build a book case or a china cabinet, the common ceiling height is about 240cm. Which means materials at 250cm. Typically, 210cm is enough height for furniture – no need to go get a ladder to grab a book from the top of a bookcase.

The sawyer (the person cutting a tree into planks) should take cracks into account. It would be wise to cut the materials slightly longer than necessary. A crack can easily extend 1-2 inches (3-5 cm) into the wood from where it stop showing on the surface. Be aware of “pith cracking” on lumber that has spent some time on the ground before they get sawn. It would be wise to arrange a big crack in the end in such a way that it is contained within one slab, if that is possible.

Slab-O-Rama!

Wide slabs are mainly useful for two purposes: wide panels in doors and those live edge slab tables (and there is a limit to how many of those the world needs – not everybody wants the Swiss alp hotel lounge look). As for the doors, 60 cm (23 5/8”) is a pretty common standard for most cabinets. Most furniture conforms to this. A 50cm wide panel would be enough. I would be hesitant to do it though – the chances for the panel cupping over time is too great. I would rather bookmatch a 25cm plank – it would be more stable.

As for thickness: Nobody really needs 10cm (4”) thick planks in oodles. A cabinet carcass at 12-19mm in thickness would be plenty. A bookcase too, unless the shelves are very wide (one could just add bracing to the design). For a table, 20-25mm (about 1”) should be pretty strong. For some dining table applications, 40mm (1.5”) could be required, but it is going to be a heavy table! Some unlucky bastards have to carry the thing out of a shop and into a house. Place it on a carpet, and the owners need to be able to move it without getting hernias when the carpet needs airing…

Now, there is one good thing about woodworking: every scrap could be useful! The offcuts from that huge dining table could be a butcher’s block, or be used in small projects. Therefore it is not a bad thing having a bit of length to the material we use. Just remember – the offcut bin fills up in a hurry!

For me, getting materials I can resaw into the desired dimensions is both an option and something I am looking for. I can get two 15mm (5/8”)boards out of a 38mm (1.5”) plank if it isn’t too much cup and / or twist in it. Three or four 8mm (5/16”) planks if I am careful and use a fine band saw blade. Perfect for the back of a bookcase or cabinet! Resawing planks is more economical and produces less waste than aiming for those dimensions at the sawmill. A couple of swipes with the smoothing plane is usually enough to remove the marks left by the band saw. A rough sawn plank needs much more cleanup, and so more wood is wasted to the dust collector bin.

Not my main product, although in quantity it certainly is…

Remember – the wider the plank, the more material will be wasted in order to get it flat and true.

For a sawyer it is important to maximize yield – the number of boards – from each trunk. For the woodworker, it is important to get as little wood in the bins as possible. When the two work in the same direction, everybody wins.

And when the woodworker is the sawyer, he/she cannot yell to anybody or anything but the mirror. It’s beautiful!

Equipment size of your shop – or your buyers

If you want to sell me materials, you should know a little about what equipment I am using in my shop. The same factors comes into play in your own shop. I think this could vary depending on which part of the globe you are located in, so do your research. I am from Norway, so my views are from a viking standpoint. I am using my equipment as the example here.

  • My band saw maxes out at 305mm / 12”. I cannot resaw anything larger than that, and in reality 28cm / 11” would be a bit of a push. It won’t be much fun resawing a 5cm (2”) thick plank at 25cm (10”) wide and 250cm (approx. 8’2”) on my own, although my band saw will handle it. Another factor here is the blade – there’s a good chance the blade won’t stay dead straight through the entire cut. It might bow and follow the path of least resistance, which means more sacrifice to the thicknesser. As you raise the blade support to make room for the cut, the length of the unsupported section of the blade increases and the chance for the blade to “cup” increases. More tension helps a little, but is not desirable to prolong blade life.
  • Planer width: My planer is 10” (25cm) wide. I cannot process boards wider than that, thus it makes no sense for me to get boards wider than that. The exception would be for live edged material, where one would cut off the sap wood anyway. In such cases I would accept boards where the narrowest part without any sapwood is up to 25 cm (10”). Of course, one could rip a 50cm (20”) slab in two, but that defies the purpose of wide material. I would not pay more for a very wide slab I have to rip down anyway. If I exceed the width of my planer, I have donkey work to do – hand planing. There is a limit to how much of that sort of thing I am interested in doing.

There are wide planers on the market, but as soon as we pass 25cm (10”), the price tag gets scary pretty quick.

Take a pass, flip and repeat. It ain’t stupid if it works!

In the image above, I show an approach to use the planer for wider materials. Take a pass, spin 180 and take a pass on the other side. Done carefully and diligently, this can do the grunt of the work before the hand planes comes out. The dangers of doing this should be self-evident! If not, do NOT do it until you understand – if you want to be able to still count to ten!

  • Thicknesser width. Not so much an issue as planer width, as there are rather cheap lunch-box thicknessers with more width than the planer / thicknesser combo’s. But in my case, I am limited to 25cm (10”), and I am not going to shell out NOK 7000 for 5cm (2”) extra width (Dewalt DW733 for example) when my planer / thicknesser costs NOK 12000!

Summary

There’s lots of ways to skin a cat, so I’ll not pretend to have a definitive answer. Hopefully, I’ve given you some food for thoughts – what to consider and what to aim for. I have not discussed wood species as a factor here, but it is. Pine, fir, birch and ash would be good alternatives for carcasses, where as oak, cherry, walnut and so on, would be a good choice for the show face of things. That being said – a piece of fir with very small and few knots would be very desirable! A big trestle table made from spruce, pine or fir would be gorgeous – especially if given a soap finish! The floor in our mountain cabin is pine which we douze with soap. We use “Grønnsåpe” – in the US I’ve heard of a brand called Pine Sol that’s similar – it is a thick, liquid soap made from natural ingredients. We use at least 50/50 soap and water, or even more soap than water. That floor is silky smooth! I love to walk bare footed on it.

In my view, quarter sawn materials should be the focus for anybody producing materials for woodworking and furniture. Quarter sawn material is incredibly stable, won’t warp much during the drying process – and in some species you get the most beautiful wood I can imagine! The ray flecking in oak, the mother of pearl effect in birch… In my view, some of the most beautiful wood figure. That being said – a quarter sawn oak floor would probably be a bit much, while a beech floor would be rather plain… It’s about balance.

Pine can be beautiful! This piece is untreated, freshly smoothed with the 04 hand plane.

Another tip for you band sawing, tree felling maniacs out there: dry your lumber! When I buy lumber, I am buying it for a project I have in mind. I do not want to wait 2-3 years before I can start building! I expect to pay way less for a green stack of wood than wood dried down to 10% (at the most! 6-7% would be ideal). In a pinch, wood that’s stabilized to the environment (around 15% moisture content where I live – I need to store the wood in my shop to get it down to 6-8%). It does take about one year per inch in thickness, unless we use kilns. And kiln drying introduces its challenges too – too rapid drying can easily leave stresses and “drying cracks” inside the wood – and nobody will know until the wood is processed further. I would be pretty pissed off if I discovered lots of drying defects. A well seasoned (meaning it has done at least one cycle of drying, gaining moisture in the summer then drying down again in the autumn) plank will not move on me, and produces higher quality furniture. I’d be willing to pay more for that!

With this thing, I don’t have to pay. That much.

If you want my business, sell me materials that are dry, seasoned and in useful dimensions I can handle in my shop.

They say that size doesn’t matter. But when you’ve got wood, it really does…

2 thoughts on “Sizing lumber

  1. Hei !
    Har nettopp snubla over bloggen din (via en kommentar du la igjen på Paul Sellers’ blogg — “… det navnet der høres da veldig norsk ut, la meg seeee…”).
    Artig lesning ! Har bare skumma gjennom de seneste postene dine så langt, men jeg skjønner jo såpass at her er det mye nyttig og interessant stoff jeg kan lære av.
    Har lagra deg blant ‘snekker-blogger’ så heretter stikker jeg innom bloggen din rett som det er 🙂
    Sjøl driver jeg et lite énmanns-snekkerverksted i en kjeller på Frogner i Oslo (ja, Frogner… ja, jeg vet… men jeg lover; jeg er ikke et rasshøl… jeg er født og oppvokst på Skedsmo, hvis dét hjelper ?) og lager egentlig alt mulig av tre som det går an å tjene penger på – det er alltid litt for lite jobber for en raring som meg, så en får være allsidig. De senere årene har det blitt mer og mer bygnings-vern-arbeid : produsere, kopiere & restaurere dører, vinduer og ymse bygningsdeler. Tømrerne har mye større budsjetter enn møbelsnekkerne 🙂 Men når jeg blir minstepensjonist skal jeg lage stoler… fiiine pinnestoler… med dreide bein… og ut-skava seter.
    Snakkes !

    • Takk for hyggelig tilbakemelding! Ikke dårlig fra en vestkantgutt! 😛 Nå tåler jeg sådant godt, ettersom jeg – som utflytta nordlending – bor SØR for Oslo. SØR for SØRINGAN! Trøste… 😀

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