Quarter Sawing White Oak

[Chico]

I didn't see anyone saying take a 6/4 bd and dress it to 3/4 one sAID 5/4 MOST LIKE MYSEL SF1 1/8 WHICH IS STOCK THICKNESS IN SAWING YOU CAN GET BY WITH LESS FOR YOURSELF BUT AS dQAN SAID i 1/8 FOR SELLING TO A CUSTOMER If you were true qtr sawing you would want it just a little heavier than 1/1/8 but bastard  qtring you can get away with 1 1/8

[ohsoloco]

When I mill, my boards are usually around 1-1/16" off the mill.  With QS white oak I get quite a few boards that BARELY clean up to 3/4"...that's cutting the board to size, jointing one face flat, and then running through the thickness planer. 

[ladylake]

I didn't see anyone saying take a 6/4 bd and dress it to 3/4 one sAID 5/4 MOST LIKE MYSEL SF1 1/8 WHICH IS STOCK THICKNESS IN SAWING YOU CAN GET BY WITH LESS FOR YOURSELF BUT AS dQAN SAID i 1/8 FOR SELLING TO A CUSTOMER If you were true qtr sawing you would want it just a little heavier than 1/1/8 but bastard  qtring you can get away with 1 1/8

  Read the end of post No 16  6/4 to make sure it will clean up at 3/4. We have guys on here saying it won't clean up from 1" to 3/4 but it will from 1-3/16 to 15/16 , that's both 1/4 inch. One says it shrinks from 1" to 7/8"  so a board cut to 8" would shrink to 7" when in fact it might shrink to 7-1/2 at worst. A lot of these numbers don't add up to me and having had my lumber sawed at 1" for years and now sawing it myself a 1" with not many boards that don't clean up to just a little over 3/4" I'll keep sawing it at 1" and advising my customers that 1-1/8 just makes a lot of shavings. I'll saw what ever size they say but have never had one insist on 1-1/8 yet. Some want 5/4 for table tops and that's what they get. I don't know if this makes a difference but I air dry my lumber to 12% then kiln dry to 6 or 7% , maybe it doesn't shrink as much that way.    Steve

[SwampDonkey]

A good rule of thumb would be to allow 1/16" in shrinkage for every 2" in dimension. I'm basing that on 20 % MC. If you go down to 8% than you loose 5/64th in dimension for every 2" in width and 3/8" for every 2" in thickness. Talking quarter sawn white oak as per topic. Of course the law of averages applies here. Using the Wood Handbook empirical shrinkage values, and calculating dimensional change based on change from green (FSP) to lower MC's. The handbook can be confusing if you don't have some knowledge on how to do the calculations. You could read the whole darn section on shrinkage and still be in the fog. The problem is parts of what you want to know are scattered all over the place. :

[SwampDonkey]

I don't know if this makes a difference but I air dry my lumber to 12% then kiln dry to 6 or 7% , maybe it doesn't shrink as much that way.    Steve

No difference, accept when your talking seasonal change in moisture. The greatest shrinkage happens in the first cycle of drying, simply because the wood probably isn't going to go in green condition again unless it's submerged. Wood shrinks when water is lost from cell walls (bound water), not from within the cell cavities (free water). This threshold varies and as a rule a thumb considered to be at 30 % MC, known as fibre saturation point or green condition. Above that no dimensional change and still green, below that, shrinkage.

[DR Buck]

Quarter saw'n definitely shrinks a lot in thickness.  I have almost a 1000 bf of QS white oak  out of the kiln that won't clean up at 3/4" because it was all sawn at 1 1/16".  :(       Now for my own use I saw EVERYTHING at 5/4 if it's going to be planed on both sides to a finished surface.  I also recommend 5/4 to my customers for the same reason.

[Chico]

Ladylake I still read 5/4 just like I did the first time and the measurements he was using really wasn't 5/4 but 1/16 heavy 4/4   :-\ and that was an observation not accusation I've sawn millions of bdft both flat and true qtr and have always sawed 1 1/8 your not going to lose any footage and you won't have probs with skip dressing  jmo

[scsmith42]

I'm going to clarify my comments a bit because my situation is somewhat unique.

Almost everything that I mill is quartersawn oak.  With my swingblade mill, I can saw logs up to 60" in diameter, and I seek out all of the 40"+ logs that I can.  I spend a lot of extra time seeking maximum width yield when I mill, due to how rare extremely large diameter logs are.

My goal is to produce the widest possible quartersawn oak boards.  At present, I have a good number of 16" - 20" wide pure QSWO boards in my kiln that came from a 50" WO log.  As we're all aware, QSWO boards that width are just about unheard of due to the scarcity of logs and difficulty handling and milling.

I currently mill everything to 5/4, because 4/4 QSO will not joint / plane out to 3/4, which is the minimum that most customers want.

My comment about milling to 6/4 is only applicable to the extremely wide boards, and that is solely so that I can joint / plane them out to make at least 3/4, if not 7/8" or 1".

The challenge is with the wood movement and the quality of the log.  Because 50" diameter oak logs are not a commodity, I have to make do with what the log can give me.  This means that there is an occasional defect in an ultra wide board, which tends to distort somewhat when in the kiln.  Depending upon the board, I'd rather leave the board wide, and have 90% of the length at full width, than edge off a defect that - although it causes distortion during drying - it still allows me to recoup full width on the rest of the board.  On an ultra wide board, it does not take a lot of distortion across the board to prevent them from jointing out during the post-drying process.

When you use a jointer/planer, as opposed to a double planer, it costs you a bit of wood thickness but yields a flatter end product.

If I mill a 16"+ board and can sell it for 2X to 3X per bd ft what a 10" wide board sells for - (because it will clean up to 3/4 across the entire length and face,) it seems to me that it makes business sense to generate some extra shavings in order to produce a higher profit product.

If I were only milling 8" - 12" wide QS boards, I would stick with 5/4 or perhaps even 1-3/16".

Make sense?

[Lil Badger Creek]

Wow, Scott,

Yes it makes perfect sense. What a great niche you are creating. I always enjoy reading about your well thought out ideas and business savvy.

I would love to hear about your method of opening up one of those big boy logs with your swing mill to quarter saw it. Do you need to start out with narrower boards till you get it open enough to double cut it? I bet those wide board are beauties!
Stephen

[scsmith42]

Stephen,

Thanks for the kind words.  You're right - the wide QS boards can be absolutely incredible.

Re milling very large logs with my Peterson, as an example we'll "mill" a long that is 50" in diameter on the small end.

Typically I study the grain layout to determine where my best opportunities for wide boards are.  I'll lay out the log so that the heart is centered in-between the rails (usually within 1/2") as well as equidastant above the rails on each end of the log.  I use a straightedge in-between the rails to measure from.  Centering the heart sacrifices some wood, but provides me with the greatest volume and quality of QS.

I will mark out a square around the heart - usually either a 6 x 6, in order to capture all of the pith wood.

Next, I'll mill the top 1/3 of the log, or top 16".  Usually I will quarter part of it in a vertical cut, and take the rest as rift.  I will mill it all of the way across, leaving a flat top (that will be around 36" across).

So now I have 2/3 of a log left (32 deep") with a 36"ish flat surface on top.  Depending upon how much QS that I can get from this third, I may make a vertical cut that will align with one side of the 6 x 6 boxed heart.

Next, I flip the log so that the flat side is down.  I'll measure off of one of the rails and shift the log to obtain the same equidistant spacing to the vertical cut that I referenced above.  I'll mill off the top 1/3 of the log again, same as mentioned above.  This leaves me with a quasi rectangular section of log that is about 16" thick (1/3 of 50" diameter) and 50" wide in the middle.

I'll make another vertical cut, to intersect the one now coming up from the bottom, and remove one side of the remaining log and set it into a second set of bunks.  I'll take out some 5/4 x 6"s above the boxed heart, as well as the 6 x 6 boxed heart, and then some more 4/4 x 6's below the boxed heart.  I can now double cut both remaining sections, which allows me to recover at least 50% of the total potential QS in the log as up to 20" wide pure QS boards.

On a 50" log, if the heart is perfectly centered by the time that we remove the sapwood and a 6 x 6 out of the middle, I can usually recover some 18" - 20" wide boards.

If this is hard to follow, let me know and I'll post some simple drawings.

Regards,

Scott

[Chico]

LadyLake 1 3/16 is heavy 4/45 5/4 standard ids 13/8 6/4 is 1 5/8not including kerf

[fat olde elf]

5/4.................no question about it.

[ladylake]

 Just restacked some 5/4 QS WO  cleaned up over 1-1/16 at 10* moister.   Guess my wood up here doesn't shrink as much or it's cut straighter or I'm more careful planing.   Steve

[SwampDonkey]

I would think maybe 1" at best, but at 8%, as I mentioned earlier, it would shrink to 1-1/16 which of course is dryer. But, to get to where your at, I think the answer lies in the MC % of your logs when milling. Might not be green, but maybe 24 % or less (just a number I'm tossing out there) when milling. Makes a difference in the expected shrinkage. Possible? Of course, my figures are based on weighted averages for the whole shooting match of white oak species, except live oak.

[ladylake]

It could be the logs, most are not real green when I saw them.   Steve

[Lil Badger Creek]

Scott,

No need for a drawing, I understand your great explanation. -When you mill the top 16 ". Do you get a 16" board or 2/8" baoards with your Peterson mill.

I have always wondered if after the big fire. If you had gotten you baker molder going --and how you like it. --- I'm still dreaming at this end, I still have a big house to sell and 2 building lots. Eventually they will sell.

Best regards,
Stephen 

[scsmith42]

Scott,

No need for a drawing, I understand your great explanation. -When you mill the top 16 ". Do you get a 16" board or 2/8" baoards with your Peterson mill.

I will mill as much of it vertically as possible (so that I'm obtaining QS), and will do either two 8's or a 10 and a 6.  Sometimes I'll take off a few inches as FS and then QS underneath it.

The Baker moulder is in place, and I've started ordering cutters for it, but still need to do the final wiring and dust collection.  I picked up the fuel line for the generator today.  Unfortunately I need to sit down and pull together some of the invoices for replacement tools and equipment that I've bought this year, and submit them to the insurance co for reimbursement.  I've got a lot of $ out of pocket and need to get it back!  That will probably occupy the latter half of this week.  Next week back on the generator though!

[Lil Badger Creek]

Scott,

The Baker moulder is in place, and I've started ordering cutters for it, but still need to do the final wiring and dust collection.  I picked up the fuel line for the generator today.  Unfortunately I need to sit down and pull together some of the invoices for replacement tools and equipment that I've bought this year, and submit them to the insurance co for reimbursement.  I've got a lot of $ out of pocket and need to get it back!  That will probably occupy the latter half of this week.  Next week back on the generator though!

Thanks for the details. I bet that insurance stuff seems like it will never end...documentation and more paper work. My prayers are with you. It is going to be exciting to have every thing up and going. What kind of dust collector are you using?  Is it a cyclone style?

[scsmith42]

Thanks for the details. I bet that insurance stuff seems like it will never end...documentation and more paper work. My prayers are with you. It is going to be exciting to have every thing up and going. What kind of dust collector are you using?  Is it a cyclone style?

The small system for my personal woodshop tools is a 3 hp Oneida cyclone.  The large system for the production equipment is an old 50" 25 hp Buffalo Forge blower.  The new shop has a room within it where a dump truck gets parked, and the shavings from the Buffalo are blown into the back of it.  The wall between the garage and the main shop is made up of filters, so I don't lose my conditioned air from inside the building.

[Traditional Toolworks]

1-3/16.  Quartersawn material will shrink more in thickness and less in width relative to plain sawn.

That is exactly the opposite what I would have thought...since the grain is vertical, it seems it should shrink in the width, not the thickness. I take your word for it, I don't have much experience in milling timber, just that it seems that the shrinking happens as the grain compresses together, I thought timber typically doesn't shrink on the end grain (length).

Cheers,
Alan

[Gblombo]

1-3/16.  Quartersawn material will shrink more in thickness and less in width relative to plain sawn.

That is exactly the opposite what I would have thought...since the grain is vertical, it seems it should shrink in the width, not the thickness. I take your word for it, I don't have much experience in milling timber, just that it seems that the shrinking happens as the grain compresses together, I thought timber typically doesn't shrink on the end grain (length).

Cheers,
Alan

Typically plane sawn lumber will shrink about 7-9% in width and 3-4% in thickness from the time it is dead green to KD 7%MC.  When you quarter saw lumber the numbers flip flop.

In the days prior to well controlled kilns and today's clear coat finishes you can imagine the benefit to wood working with quartersawn material.  The expansion and contractions of floors and raised panels would be much less extreme with quartersawn parts.

This is an worth considering if you are a buyer of KD QS lumber as the net board footage comes from less gross board footage  than you would ordinarily expect.

Greg

[Traditional Toolworks]

Typically plane sawn lumber will shrink about 7-9% in width and 3-4% in thickness from the time it is dead green to KD 7%MC.  When you quarter saw lumber the numbers flip flop.

This makes sense to me as the grain is neither vertical or cross.

When you say the numbers flip flop, that must be a generalized comment, as that would surely depend on the direction of the grain.

I'm confused on how the numbers could flip flop in regard to cutting quarter sawn though, if it is truly QS. I would think the shrinkage would be much less for QS as the grain is vertical, so the thickness should change very little.

This is obviously one of those situations where what looks right on paper and what happens in the real world is not the same thing.

If I had a sawmill right now I'd go cut some and wait for it to dry...then see if the numbers flip flop ;)

Has anyone done this experiment themselves and if so, what were the results?

Cheers,
Alan

[SwampDonkey]

I thought timber typically doesn't shrink on the end grain (length).

It doesn't by much, so it's negligible.

When you say the numbers flip flop, that must be a generalized comment, as that would surely depend on the direction of the grain.

It is general because the longer the log, and the taper, limit how perfect the quartering is. Trees grow somewhat conically not cylindrically.

I'm confused on how the numbers could flip flop in regard to cutting quarter sawn though, if it is truly QS. I would think the shrinkage would be much less for QS as the grain is vertical, so the thickness should change very little.

You have to understand radial growth (pith to bark, ring thickness) and tangential within a ring in circumference of the tree. The tree is putting on cell growth in 3 directions. The longitudinal is vertical growth, the part with little shrinkage when drying. When your flat sawing your peeling off layers of growth, on the wide side. Not quite like slicing veneer since your cutting through rings because a tree doesn't grow square. If you look on the edge of the board you see a quartered appearance where you have split down through the rings. In quarter sawed you are splitting down through the rings on the wide side of the board and looking from edge to edge shows layers of growth rings. Just the opposite to flat sawed. Tangential shrinkage is more pronounced than in the radial direction. This is why it flip flops. The physical properties of wood don't change no matter how you saw it. It's an illusion if you don't understand what is going on. ;) Shrinkage within a ring varies in relation to early wood and late wood as well. Early wood is less dense.

The only vertical grain would be on the end grain (cross sectionial view), like the end of the board. In quartering your looking across the radial growth.

I had to make a little edit. ;)

[Traditional Toolworks]

You have to understand radial growth (pith to bark, ring thickness) and tangential within a ring in circumference of the tree. The tree is putting on cell growth in 3 directions. The longitudinal is vertical growth, the part with little shrinkage when drying. When your flat sawing your peeling off layers of growth, on the wide side. Not quite like slicing veneer since your cutting through rings because a tree doesn't grow square. If you look on the edge of the board you see a quartered appearance where you have split down through the rings. In quarter sawed you are splitting down through the rings on the wide side of the board and looking from edge to edge shows layers of growth rings. Just the opposite to flat sawed. Tangential shrinkage is more pronounced than in the radial direction. This is why it flip flops. The physical properties of wood don't change no matter how you saw it. It's an illusion if you don't understand what is going on. ;) Shrinkage within a ring varies in relation to early wood and late wood as well. Early wood is less dense.

I don't totally understand how to correctly quarter saw a log, I guess, been trying to find that info, but see a couple different methods.

Wouldn't you try to saw across the pith from butt to tip? IOW, don't you need to quarter it based on the pith? I was thinking if you match the pith at the same height at both tip/butt, saw it, then flip and do again, one would then quarter saw the quarters, but taking each side off at a time. Is there a better method that allows this to be done without quartering the timber? As you might tell, I don't have a lot of milling experience and looking for a mill now...

Cheers,
Alan

[LeeB]

Allen, try to find the book by Bruce Hoadly called Understanding Wood. A good book to help you understand why wood does the things it does and how it is made up.