Thread: Backsawn v ¼sawn - understanding the difference - a few Qs

Fence,

My understanding is that yes, there is some nomenclature you are missing, and that phrase is "rift sawn". It's all about the angle of the end grain. If the end grain rings are at ~80 - 90 to the face of the board (all these numbers will vary from "expert" to "expert"), that is a quartersawn board. If all of the boards from a log have that characteristic, then that is a quartersawn log, as you have shown on the right with immense waste.

When you do what you have pictured in the middle there, you will have boards with grain between - and I'm making these numbers up - ~45 - 80 deg to the face. These would be rift sawn boards. My understanding is that a more typical way of rift sawing a log would be to alternate directions of sawing. So imagine you have a quartered log. You saw a board off of one of the two flat faces, then another off of the opposite flat face, and then back to the other, repeating this process until there is nothing left to saw off of the quarter.

Your take on backsawing is the same as mine.

I believe that a lot of millers and lumber yards throw the phrase "quartersawn" around a lot when in fact the rings may be as low as ~60deg from the face.

I've been studying this stuff because my cousin and I plan to mill a walnut tree by hand when I visit the States for the holidays. We are going to quarter it and then rift saw.

Which reminds me I need to eat some Wheat Bix and work out...

Hope that answers your question.

Luke

After thinking about this some more... I see where the confusion comes from. To say that a BOARD is quartersawn is kind of silly. The LOG was quartersawn. The board is just the result of quartersawing. Same with rift sawing and backsawing. That's the technique of milling. The resulting boards can have highly variable end grain angles.

The nomenclature is interchanged, but, technically, unless you TRUE quartersaw a log, with all of that waste, then backsawing will produce "quartersawn boards", "backsawn boards", and, closer to the heart, "riftsawn boards", just like rift sawing will produce both "quartersawn boards" and "riftsawn boards".

I feel like in order to eliminate that confusion, the system of describing the boards should have a different nomenclature from the system of describing the milling technique... So I guess we're having this conversation a few hundred years late.

your first image would be "plain sawn" or "flat sawn" or "slabbed". produces anything from backsawn boards, 1/4sawn and rift sawn. the second image I dont think anyone does. and your third image is "rift sawn" (doesnt make rift sawn boards though ) or I believe it is refered to as "radial sawn" wastes so much timber, you would need to specifically ask, and pay for it.
SawingQSRift4.jpg
i like the modern 1/4 sawing method because i get the figured stuff from the actual 1/4sawn boards, and i get to glue up legs from the rift sawn (which really shouldnt be shipped to me as 1/4sawn but mills do whateva they like).

backsawing produces only backsawn boards, also reffered to as tangental cut. the center pith is usually waste.
backsawn.jpg

Here's the thing, right?
Theres 5 different designations of timber based on grain orientation to the face of the board.
back/ plain sawn has the grain at 0 to 30
rift has the grain at 30 to 60
quartersawn has the grain at 60 to 90
radial quarter or true quarter has the grain at 80 to 90
flat or true back has the grain at 0 to 10

for certain applications each of them is desireable, but the last two are rarely if ever used, and mostly timber is either described as quarter being 45 to 90, and back sawn being 0 to 45. rift is the least understood, and a lot of what goes into a pack of either the above is technically rift sawn. Most cut patterns give a mix of either back and rift or quarter and rift which is probably why.

choosing a cut pattern to suit a log size and desired yield is one of the reasons that a good number 1 bench hand is so sought after. There's a whole hell of a lot more patterns out there then just the two or three you'll see commonly illustrated. There's also a lot of illustrations that are just plain wrong, mostly it's a mislabeling thing. The one Kuffy is labeling radial being a prime example: you'll see that all over the Internet with rift attached to it but it's a long board quarter sawn pattern that delivers little if any rift at all. The advantage of that pattern over his other quarter cut pattern is that it gives a higher yield of wide boards off a given log at the cost of higher waste age. the other wastes less timber but you get a higher recovery of narrow boards. Radial quartering is a different pattern again.

if I was more computer savvy I'd know how to draw different patterns to illustrate, but sadly I'm not. If I get time at some point I'll trawl the web and find some illustrations and put a commentary beside them but time is something I haven't got much of lately.

Thanks very much for those detailed answers chaps. Nails it down, and easy to see why radial ¼sawn wouldn't be done much if ever.

Coming back to my question about a square profile:
Often it will be a rift sawn billet, but in the case where the rings are around 80-90° to one face it would then be both true ¼ and flat back, and would no doubt be classified as ¼ sawn given the increased desirability - yes?

So does that mean that it is the larger dimension face that will govern the classification, given that every billet is a combo of both unless it's rift sawn?

I have a good understanding of what is and what isn't Quarter sawn!
And how to achieve it successfully through clever,methodical milling.
Maybe one day you'll leave that dreaded place they call N.S.W,and come up to sunny,warm QLD for a few days and help me work the Lucas.
Learn all the tricks and drool over some fiddleback ...MM

heres a picture showing four common quarter sawing patterns and also a page illustrating an industry standard "quarter cutting" pattern as used in a typical eucalypt sawmill. Image I found on the web, the pdf is an extract from the "Australian Timber Handbook"by Norman K Wallis, mine is the second edition published in 1963, but that very pattern got used here today.

Thanks John, that's excellent info.

The radial sawing pattern illustrated is a "true" quartercut pattern. As you can see it wastes a lot of wood and its not used much except for providing boards that are exactly that... cut dead on the quarter or that close to it it doesn't matter. Generally speaking it is only used when cutting for a very small market niche called premium acoustic stringed instruments - violins, guitars and the like. It is unsuited to small logs, a major PITA to bench, and not on the list of things you do for fun. It is however, as with most premium niche markets, quite lucrative if you have the skills, equipment, logs, and market contacts to utilise it.

Alternate quarter sawing is far more common pattern, suited to smaller logs. The trick with that one is to run a double bench with 4 guys. The flitch passes over the first bench and then transfers to the next bench to come back, with a board taken every pass. This means it only needs to be rolled to sit against the 2nd fence. Watching four guys bench who know how to do this is truely poetry in motion, and for all the modern equipment available nonthing can properly quartersaw like a 4 man bench. Running that pattern on a single bench requires that the flitch be end for ended after every cut to put a sawn face against the fence. The outside boards as well as being small are technically rift sawn not quartersawn.

Common quarter sawing is a "big log" pattern. It gives a far higher yield of wide quartered boards then the rest, although again the narrow boards on the end of each quarter are technically rift sawn. What we're doing is trading lower recovery for a width premium. Usual method is to quarter the log, then set each quarter on a bunk and give it another pass through the #1 to remove a bit of sapwood and make a flat edge for it to rest on when it gets to the bench, From there we take a couple of swipes off one side, then turn the flitch ( Because we don't have two breast benches here) and come back in from the outside to finish.

Double or triple quartering is basicly a poor mans alternate pattern. I say poor mans because its for mugs like me who only have one bench rather then the two required for high speed alternate cutting. Basicly I can cut a couple of boards before I need to end for end my flitch. Again it suits smaller diameter logs.

With any of these patterns there is a need to then saw edges on the timber. Thats what #3 benches are for!


The pdf is a standard eucalypt pattern as used for producing flooring. Logs are broken on the #1 into flitches and cants in a log size dependant pattern designed to give max yield on the bench, with the location of each initial cut determined by the desired board size. As a pattern its also suited to putting flitches in front of a one man bench, and I've been known to replicate it in principal with a Lucas Mill too. It's a far more practical pattern, then the above, and suits the euc industries definition of a quartersawn board - which is 45 to 90 degrees. Lets be honest here: that is set by resistance to collapse during drying, not by stability in service considerations. If it wasnt for the collapse issue the entire Tas Oak/ Vic Ash milling community would shift to backsawing in a heartbeat.

Backsawing patterns I'll cover tomorrow or the day after when I get time.

NB: These are all just lines on a piece of paper, and the reality is that as soon as the first cut goes into a log all good intentions can go out the window according to the amount of stress in the log...

Originally Posted by FenceFurniture

Thanks very much for those detailed answers chaps. Nails it down, and easy to see why radial ¼sawn wouldn't be done much if ever.

Coming back to my question about a square profile:
Often it will be a rift sawn billet, but in the case where the rings are around 80-90° to one face it would then be both true ¼ and flat back, and would no doubt be classified as ¼ sawn given the increased desirability - yes?

So does that mean that it is the larger dimension face that will govern the classification, given that every billet is a combo of both unless it's rift sawn?

YUP! Grain orientation is always measured to the faces of the board not the edges. A square section has four faces, so its either quarter and flat, or more desireably rift (ie grain runs from corner to opposite corner rather then face to opposite face). In timbers like oak with a distinct grain differnece between the two aspects rift tends to give a more uniform appearance.

Saying a square section is "Quarter sawn" is just good marketing, or preying on the gullibility of those who dont know better if you want to be cynical.