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Twisted Timbers

Started by Rougespear, August 16, 2016, 10:36:55 PM

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Rougespear

I suppose like most everyone else, timbers come off my mill straight and square.  However, I am having many twist terribly though now after a month since being milled.  They are all 4x6's meant for floor joists in my timber frame, but now they're more like expensive firewood.  They all came from small trees.  I have also been cutting 4x8's from larger trees (12" rounds) and they seem to be faring slightly better, but some are still twisting.  It is hot here right now (80-90F).  I have kept the timbers out of direct sunlight and straight and level dunnage, and they're stickered every 18".  All hearts have been carefully centered/boxed within the timbers.

So, how can I prevent/mitigate twisted timbers?  I can't really make use of twisted timbers in my frame.  Should I cut all the timbers oversized by an inch, let sit for a few months, and then re-mill them?  Seems wasteful, but if that's what it takes then so be it!

My wife is getting interesting (bad) looks on her face when she sees all our hard work and money "twisting" away to firewood.  I'm not sure how to move forward... does anyone have suggestions?
Custom built Cook's-style hydraulic bandmill.

WV Sawmiller

   I am sure bigger, straighter logs will yield straighter timbers. You did not mention what kind of logs they are. Some woods will just naturally twist more than other. How much weight are you keeping on top of the wood when stickered. That can be a factor in addition to the direct sunlight, airflow, and heat.
Howard Green
WM LT35HDG25(2015) , 2011 4WD F150 Ford Lariat PU, Kawasaki 650 ATV, Stihl 440 Chainsaw, homemade logging arch (w/custom built rear log dolly), JD 750 w/4' wide Bushhog brand FEL

Dad always said "You can shear a sheep a bunch of times but you can only skin him once

cliffreaves

Sheesh!  I'm sorry for your troubles.   I know someone on here will have good advice.

Rougespear

The timbers are interior douglas fir.  Weight on top is only about 250 pounds.  I am getting ready to get into the larger of my trees (26"+) but I'd like to understand whether I should also expect timbers from those large trees to also twist, before I begin wacking those sticks up.

Do larger diameter trees typically yield better timbers?
Custom built Cook's-style hydraulic bandmill.

ladylake


  They never dry straight, if you want them straight saw oversize and resaw right before using them.  Steve
Timberking B20  18000  hours +  Case75xt grapple + forks+8" snow bucket + dirt bucket   770 Oliver   Lots(too many) of chainsaws, Like the Echo saws and the Stihl and Husky     W5  Case loader   1  trailers  Wright sharpener     Suffolk  setter Volvo MCT125c skid loader

WDH

The best luck that I have had was sawing them oversize, letting them dry for about 6 weeks, then re-sawing them to final dimension.  They twist and warp the most when they are at the higher moisture content, and letting them pre-dry for a while allows most of the bad things that are going to happen, happen, then you can deal with them. 
Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

Rougespear

Fair enough... I will saw oversize! 

What is a good oversize dimension for 14' - 20' timbers?  I'm thinking 1", but have you folks found that to be too little to take out any serious twisting that may occur?
Custom built Cook's-style hydraulic bandmill.

uler3161

Somewhere I have a book that suggests 1/8" for every inch of thickness and width. I don't recall it saying anything about how long the timber is, but I suspect that might matter, especially for extra long timbers. Most of the timbers we cut are 16' long and I think 1/8" per inch would be good for even the worst timbers we have.
1989 LT40HD, WoodMaster 718

Dan

Brad_bb

Yes I've learned to saw oversize when they are not going to be cut and assembled right away, which is always for me.   I later plane them with my beam planer to get them square and straight again, but if I didn't have that, I'd oversize them even more so I could re-mill.  Although it takes many years for a timber to dry completely, you only need them to dry enough on the outside to keep them stable enough for long enough to be able to use them.  For the last month, I've been planing curved natural edge knee brace stock that I milled a year and a few months ago.  Walnut, Mulberry, Osage, Cherry, Ash, and some have twisted up to 3/8". Most probably average 3/16" over 6 feet.  These are 3"-6" thick and are stable enough now to plane flat and I'm not worried about movement.
Anything someone can design, I can sure figure out how to fix!
If I say it\\\\\\\'s going to take so long, multiply that by at least 3!

Satamax

Well, i'll open my big gob!

I'm not a sawyer yet. But there's things i've learned here and listening to the old guys.

First of all. Never saw anything smaller than 12 inches of the small end. That's not worth it. This i learned here.

Then listening to the older guys where i live. I've heard plenty of gibberish. But also one piece of sound advice. Never saw timber turning to the left.  I mean. If the bark grooves are turning to the left the furthest away you look from the bottom or top of the tree. It will twist.  If the bark is removed and the wood has started to dry a smidge, there's slight sapwood cracks. Again, is the turn to the left, don't saw. Every time i've seen sawn timber twist real bad, guess which way the cracks were turning? Yep, to the left.

To tell if this is forklore or else. I can't tell you more. But since i've been told. Every time i see a twisty bit of wood, and pay attention. Cracks are running to the left.

Another bit, If you face center your small logs, check if you can avoid the pith at the small end. Otherwise, it's better practice to box the pith in the center of the whole joist. Or on it's edge.

Another one, ratchet strap your stickered joist piles. If possible at each sticker line. ( or use plastic or metal straps if availlable)

Fit your wood green can also give you good results. If it's all nailed tto what's below, and to the boards, it might disuade it to show it's temper.
French CD4 sawmill. Latil TL 73. Self moving hydraulic crane. Iveco daily 4x4 lwb dead as of 06/2020. Replaced by a Brimont TL80 CSA.

Brucer

I've cut a lot of 4x6 D-Fir for timber framers over the years, with few complaints. Usually they would try to use them green but sometimes life got in the way. If they had to store them they would stack and sticker them, cover them with lumber tarps (NOT hardware store tarps), and add some weight to the top of the pile.

I never bought logs less than 12" diameter at the top. Any timbers under 4" I would saw FOHC (Free of Heart Centre). For a 12" top I could get two timbers out of a log (staying an inch away from the pith on either side). For a 14" top I could get three timbers, which gave me slightly better recovery.

Some folks will tell you that keeping the heart in a timber will prevent twisting, and FOHC timbers are more likely to twist. That hasn't been my experience. A timber is either going to twist a lot, or it's not, regardless of where the centre is.

I just pulled a 4x8x12' FOHC D-Fir timber out of my garage, where it had been sitting on a rack just below the trusses for 15 years. Dead straight, no twisting.

I had a customer defer adding a deck to their timber frame house for two years, after I cut the timbers. 3 pieces, 8x12x18', all with the heart centred, all badly twisted. They had me cut new ones and asked me to see if I could resaw and sell the twisted ones. I hung onto them for two years before I found a customer who wanted 6x10's, so I resawed the timbers and got the original customer a good chunk of their money back. Even though those timbers had sat for 4 years before I sawed out the twist, they still twisted after they were installed :o. Fortunately the new customer really likes the "funky" look.

I have read that the fibres in a growing tree first twist in one direction, and then after several years twist in the opposite direction. That may be why bigger trees are more stable; the two directions of twist counteract each other. On the other hand, I've found that trees from one micro-climate seem to behave the same way. My brother owns a lakeside acreage and every D-Fir that we cut down on it has shake and serious twist.
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Ron Wenrich

You might have some genetics involved in the lakeside timber, as well.
Never under estimate the power of stupid people in large groups.

Czech_Made

Or local conditions - such as the wind always blows this way.


Satamax

Brucer, would you mind looking which way the splits turn, next time you have some of this lake wood nearby? I would be really interested in knowing if they turn left.

Thanks.

Max.
French CD4 sawmill. Latil TL 73. Self moving hydraulic crane. Iveco daily 4x4 lwb dead as of 06/2020. Replaced by a Brimont TL80 CSA.

Glenn Ohman

I'm sure there has been some scientific research done on this subject -- look through the Dissertations/Theses databases from schools like Oregon State University.

Glenn

Rougespear

Quote from: Brucer on August 17, 2016, 10:07:34 PM
I've cut a lot of 4x6 D-Fir for timber framers over the years, with few complaints. Usually they would try to use them green but sometimes life got in the way. If they had to store them they would stack and sticker them, cover them with lumber tarps (NOT hardware store tarps), and add some weight to the top of the pile.

I never bought logs less than 12" diameter at the top. Any timbers under 4" I would saw FOHC (Free of Heart Centre). For a 12" top I could get two timbers out of a log (staying an inch away from the pith on either side). For a 14" top I could get three timbers, which gave me slightly better recovery.

Some folks will tell you that keeping the heart in a timber will prevent twisting, and FOHC timbers are more likely to twist. That hasn't been my experience. A timber is either going to twist a lot, or it's not, regardless of where the centre is.

I just pulled a 4x8x12' FOHC D-Fir timber out of my garage, where it had been sitting on a rack just below the trusses for 15 years. Dead straight, no twisting.

I had a customer defer adding a deck to their timber frame house for two years, after I cut the timbers. 3 pieces, 8x12x18', all with the heart centred, all badly twisted. They had me cut new ones and asked me to see if I could resaw and sell the twisted ones. I hung onto them for two years before I found a customer who wanted 6x10's, so I resawed the timbers and got the original customer a good chunk of their money back. Even though those timbers had sat for 4 years before I sawed out the twist, they still twisted after they were installed :o. Fortunately the new customer really likes the "funky" look.

I have read that the fibres in a growing tree first twist in one direction, and then after several years twist in the opposite direction. That may be why bigger trees are more stable; the two directions of twist counteract each other. On the other hand, I've found that trees from one micro-climate seem to behave the same way. My brother owns a lakeside acreage and every D-Fir that we cut down on it has shake and serious twist.

This is the first time I've read a recommendation to deviate from boxing the heart within timbers... I'm not saying its bad, just different from the norm.  Is there a size of tree where you begin to use this strategy?  How many others are doing this?
Custom built Cook's-style hydraulic bandmill.

Brucer

Keep in mind, I'm talking mainly about Douglas-Fir here.

The timber framers I worked with preferred FOHC timbers. Getting up to 8x8 and bigger they realized that price would be a factor (big logs = big $) so would usually give the customer the choice. However, for brace material -- 4x6, 4x8, 4x10 they would insist on FOHC timbers.

For one project I cut 36 FOHC rafters, all 4x12x30'. None of my timbers have wane on them -- timber framers like that. I always cut at least 1" to the side of the pith.


One of my first jobs for a timber frame company was canting up some 30" plus Ponderosa pine into FOHC cants. The owner had been given the logs for the cost of shipping, and wanted it broken down into pieces that would not check much while in storage. He wanted lots of wane so he had some flexibility with what he'd eventually have me saw out of these.


My second job for the same company included 10 FOHC 8x12's 16' long  :o. The logs were 24" at the top (and I had a manual LT40 at the time).

There's a company in Squamish BC that specialized in kiln-dried FOHC Dougals-Fir up to 8x12 and bigger. They're using coastal Douglas-Fir which grows quite a bit bigger than interior Douglas-Fir.

As I said, I always buy good quality logs with at least 12" tops. I don't take anything with shake, large knots, or excessive spiral grain.
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Brad_bb

I can tell you, with very high quality FOHC white Oak 4x6 and 4x8 I used as rafters bowed significantly, some twist.  We ratchet strapped and blocked to get most of the bow out when putting up the sheathing to hold it.  The extra high cost of FOHC white Oak in long lengths, was not worth it with the culls, and the extra work to make them work.

These were the leftovers.  The worst culls were cut up into 4 ft pieces and planed square and used as long heavy stair treads.  Some very expensive treads at $4.50-6.00/BF!



 


 

The lessons I learned were
1. Break up your  rafters into shorter pieces , which means shorter logs, which means less cost.
2. If you have time, cut your pieces oversize and let them dry for a year and then remill or plane them (I have a beam planer making this step fairly easy.  But if you have FOHC oak timbers, oversizing will not help as they can bow way too much.


I have no experience with green Doug Fir.
Anything someone can design, I can sure figure out how to fix!
If I say it\\\\\\\'s going to take so long, multiply that by at least 3!

Brucer

I have a lot of experience with interior Douglas-Fir ... about 400,000 BF worth. And that's the species the original post was about.

The only Oak native to British Columbia is the Garry Oak, which only grows in the southern coastal region. No doubt if I was sawing this species I'd be treating it differently:
  "Although the wood has a beautiful grain, it is difficult to season without warping ..."

Many species will bow when you saw out the heart. Around here that would be Western Red Cedar, Birch, and Trembling Aspen. But as you can see from my first photo, there is very little bowing with Douglas-Fir, even in a 30' timber. That isn't always the case but I don't see too many FOHC timbers that bow more than about 1/4" over the length.
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Rougespear

Thanks Brad... those are some terribly narly timbers... sorry to hear also of your troubles.

Well Brucer, you've definitely peaked my interest!  I'm also sawing interior Doug Fir that was harvested just down the road from me.  To make up the rest of my dry-belt low-elevation doug fir I harvested from my land, I ordered another 25m3 of 50' saw logs... a total of 12 came in 50' lengths, 10 of which were no smaller than 12" at the top (2 were basically culled into 2x6 T&G material).  From the butt 14' of 5 of the logs I bought I planned to "box the heart" within an 8x10 post, and then saw 4x 4x8 rafters FOHC flanking the post.  I'd be interested in learning some more from your experience!  Thanks for the information.
Custom built Cook's-style hydraulic bandmill.

Brucer

Brent, I got your message but my out-of-date browser doesn't like to send replies to PM messages ???.  Send me a quick e-mail (click on the envelope symbol on the left of one of my posts - just below "The Kootenay Sawyer").
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

redbeard

 BC Douglas fir is the best, there's some good tracts left in North West Washington but British Columbia has the best. Those logs on your deck Brucer are some real beauties. I love finding logs like that where the SAP wood is only a 1" wide. Big firs with big heart wood make the best beams. And beautiful board n bat siding.

 
Whidbey Woodworks and Custom Milling  2019 Cooks AC 3662T High production band mill and a Hud-son 60 Diesel wide cut bandmill  JD 2240 50hp Tractor with 145 loader IR 1044 all terrain fork lift  Cooks sharp

WDH

I milled some timbers out of some smaller pines.  I boxed the heart and sawed then at 4.25" x 4.25" x 10' long.  I air dried them for six weeks, then into the kiln and dried them to 8% moisture content.  Every single one dried with some twist, some worse than others.  In that state, they were unusable for table legs.  I ran them over the jointer to get two flat sides 90 degrees to each other, then planed them down.  They came out perfectly straight and flat (thanks to the jointer).  They all finished planed down to 3 & 9/16" x 3 & 9/16".  Just right for farm table legs.  So, they were sawn about 3/4" oversize at 10' long, and that was the absolute minimum that I could have gotten away with.  For longer lengths, I think that you would have to saw them more oversized. 
Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

Brucer

Redbeard, you're right, they really are beautiful logs. Straight, too :) :).

I buy them from a plywood veneer plant. They want the best D-Fir logs (no shake, small knots) and have the clout to demand the best from the local loggers. They aren't too concerned with sweep because all the logs will be bucked to 8'-8" for the lathe. They will pull the straightest logs out of their inventory for log home builders and small sawyers like me. They'll also mark them up 70% :o.

I paid $160/m3, delivered, for the logs in that photo. With a recovery for 300 BF/m3 I was paying $0.53 per BF. A few people thought I was crazy paying those prices, but I'd done my homework.

When I was sawing for the timber frame company, they were paying anywhere from $80 (junk) to $130 (pretty good) per m3. Over a one year period, their average price including delivery worked out to $112.50/m3, a lot less then what I ended up paying. However, in one year I sawed 84,000 BF for the timber framer from 400 m3 of his logs. That's a recovery of only 210 BF/m3 so they were paying $0.54 per BF, just a tad more than I was paying.

For essentially the same price I had 30% less waste to deal with. The other big plus was that virtually every timber I sawed was a #1 structural or select structural -- the best structural grades.
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Brucer

Quote from: Czech_Made on August 18, 2016, 06:34:55 AM
Or local conditions - such as the wind always blows this way.

The lake is the flooded bottom of a valley in the mountains. The valley runs North-South and the wind (when it blows) is either from the North or the South. The only thing predictable about the wind is that it will die as soon as you go sailing on it ;D.

Quote from: Satamax on August 18, 2016, 07:30:08 AM
Brucer, would you mind looking which way the splits turn, next time you have some of this lake wood nearby? I would be really interested in knowing if they turn left.

I was out that way last week.  They all turn to the right.

Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Satamax

Thanks a lot Brucer.


Soo, i might be talking gibberish biiiiiigggg time then! ;D

French CD4 sawmill. Latil TL 73. Self moving hydraulic crane. Iveco daily 4x4 lwb dead as of 06/2020. Replaced by a Brimont TL80 CSA.

ozarkgem

Quote from: Brucer on August 21, 2016, 01:51:32 AM
Redbeard, you're right, they really are beautiful logs. Straight, too :) :).

I buy them from a plywood veneer plant. They want the best D-Fir logs (no shake, small knots) and have the clout to demand the best from the local loggers. They aren't too concerned with sweep because all the logs will be bucked to 8'-8" for the lathe. They will pull the straightest logs out of their inventory for log home builders and small sawyers like me. They'll also mark them up 70% :o.

I paid $160/m3, delivered, for the logs in that photo. With a recovery for 300 BF/m3 I was paying $0.53 per BF. A few people thought I was crazy paying those prices, but I'd done my homework.

When I was sawing for the timber frame company, they were paying anywhere from $80 (junk) to $130 (pretty good) per m3. Over a one year period, their average price including delivery worked out to $112.50/m3, a lot less then what I ended up paying. However, in one year I sawed 84,000 BF for the timber framer from 400 m3 of his logs. That's a recovery of only 210 BF/m3 so they were paying $0.54 per BF, just a tad more than I was paying.

For essentially the same price I had 30% less waste to deal with. The other big plus was that virtually every timber I sawed was a #1 structural or select structural -- the best structural grades.
what does $160/m3, mean?  the 3 is throwing me.
Mighty Mite Band Mill, Case Backhoe, 763 Bobcat, Ford 3400 w/FEL , 1962 Ford 4000, Int dump truck, Clark forklift, lots of trailers. Stihl 046 Magnum, 029 Stihl. complete machine shop to keep everything going.

WDH

Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

Satamax

Ozarkgem, usualy, in most of mainland europe, wood is sold by cubic meter.

Surface of the log cut at midpoint times the length for logs;

Width x thickness x length for planks or beams.

160 delivered is a bit dear, imho. But i'm in euroland. Over here, you can say 70€ per cube for sawing pines, 90 for larch, 80 to 120 for oak.
French CD4 sawmill. Latil TL 73. Self moving hydraulic crane. Iveco daily 4x4 lwb dead as of 06/2020. Replaced by a Brimont TL80 CSA.

WDH

In pine, a cubic meter is pretty close to a US ton (2000 pounds). 
Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

Brucer

Quote from: Satamax on September 13, 2016, 08:04:23 AM
  ...160 delivered is a bit dear, imho.

I agree, but it's worth it. These are much better than sawlogs. More to the point, I made money sawing them. I have always beat my competition on quality, never on price.
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Satamax

Quote from: Brucer on September 13, 2016, 11:54:41 PM
Quote from: Satamax on September 13, 2016, 08:04:23 AM
  ...160 delivered is a bit dear, imho.

I agree, but it's worth it. These are much better than sawlogs. More to the point, I made money sawing them. I have always beat my competition on quality, never on price.
Yep, i totaly agree. Beating the competition on price isn't rewarding mentally at all. I have a competitor, a guy i subcontracted for in the past, who does absolute crap, for cheap. To the point i wonder how he still gets jobs. I wouldn't like to be in his place. Where everybody in the valley diss him for doing crap.

Sawing wise, i hope i can do what Percy talks about in the sitka thread. Guitarmaking wood. With caviar logs. Some cabinet grade figured woods. Etc. No point in trying to beat others on volume. There's big guys less than a hundred miles from me. Which i'm not even willing to try to beat.  Stay small and human.
French CD4 sawmill. Latil TL 73. Self moving hydraulic crane. Iveco daily 4x4 lwb dead as of 06/2020. Replaced by a Brimont TL80 CSA.

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