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OK pros. what happened??

Started by flip, March 01, 2007, 01:25:44 PM

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flip

The pics. here are of 5/4 cherry that was cut last summer and air dried down to an average of 10% (according to my Lingomat).  Was stacked in the middle of a large stack and dried under a shed.  I put about 400bf into my DH kiln to wring the remaining water out, which yielded about 3 gallons in 5 days.  I had the heat cranked  and maxed out at about 130 on the 4 th and 5th days.  Most of my lumber came out fine but I have several boards that have this defect.  I had about 600lb on the stack while in the kiln drying.  Any ideas what happened.  My kiln is an Ebac LD 3000 but my temp. and humidity probes are VERY primitive.  Any idears?









 
Thanks for any advice or comments
Flip
Timberking B-20, Hydraulics make me board quick

Tom

I believe that you are looking at the "heart check" that develops from the immature wood around the pith.  It is present, visibly, in most logs and extends, invisibly, beyond.  Drying causes shrinkage and twisting that allows the check to open up and become quite noticeable.

It is in the center of the tree and the boards will usually be vertical grain.  It is well worth a dedicated woodworker's efforts to glean the "good" wood around the check.

flip

That was my suspicion.  I got greedy and sawed the whole thing down instead of leaving a 4x4 on the pith.  I've been cutting around the bad spots to get the most wood I can.  I'm wonder if I would have not put it to it in the kiln if the cracking and bowing would have been less overstated.
Timberking B-20, Hydraulics make me board quick

Ianab

What Tom said.



That bit of wood around the pith is bad news, it will warp like crazy because of the changing orientation of the grain, and will often split, just cos it feel like it  ::) Air drying doesn't seem to help much

Cheers

Ian
Weekend warrior, Peterson JP test pilot, Dolmar 7900 and Stihl MS310 saws and  the usual collection of power tools :)

Tom

Nah, you would have had it anyway because it was there to begin with.  You just didn't see it all.

Don't think of it as being greedy.  That's still good lumber around the heart check.  It just has to be found.  A good Cabinet maker would rather you gave him that in a board than throw it away.  If you cut it into a 4x4 it will still have the cracks and won't be good for turning.  You did right. :)

I keep a lot of those boards like that for myself if the customer doesn't see the beauty.  Some of them will throw them on the slab pile.   I go get them and put them on the truck.  You can get some really good looking quarter-sawn boards if you take the time.  

It's amazing how much pretty lumber is thrown away because the carpenter can't see it.  They want the board to be perfect from one end to the  other, even if they are going to use only short pieces.

I have one customer in particular who will have me cut an almost flawless 1x12 down to 1x6 because it has a little wane on one end.  Kinda like throwing the baby out with the bath water.

I've got others who will use every stick that comes off of the mill.  I usually give them a big break on the bill because I admire them. :)


flip

Thanks!

I have a few other boards that came out of the same log in the same part of the stack, I think they were too close to the pith also, seemed localized to one part of the stack.

I glued up several boards last night for a top of a cabinet I'm making.  Left 'em a little heavy so I can run back through the planer, talk about a bear to get straight and glued ::)
Timberking B-20, Hydraulics make me board quick

Tom

Yeah, like Ian said, that immature wood around the pith will move around.  Sometimes it is difficult to machine too.

ohsoloco

I'm with you, Tom.  Look at all of that nice vertical grain wood on the right of the board in the top pic  :)  Think about when you're building cabinet doors.  Lots of rails and stiles are less than 4" wide, and typically pretty short  ;)

Mr Mom

     One quick question. If the pith is so unstable how come they make poles out of them for pole barns??
     Just another dumb question from a new guy.




     Thanks Alot Mr Mom

Tom

Because, in a pole, the pith is encapsulated and the growth rings are unbroken.  It makes for a mighty stout piece of vertical support.

SwampDonkey

That's what I would suspect, as Tom and Ian explained it. I have quite a few boards like that and I use them, especially the 2" stock, I can make a few turned legs from those boards. The 1"or 7/8 board is good for 1/8" thin strips for facing or coverings ends of plywood . I hate to toss anything in the stove.  :D
"No amount of belief makes something a fact." James Randi

1 Thessalonians 5:21

2020 Polaris Ranger 570 to forward firewood, Husqvarna 555 XT Pro, Stihl FS560 clearing saw and continuously thinning my ground, on the side. Grow them trees. (((o)))

oakiemac

First problem is that you are using an Ebac ;)
If you think I dislike Ebac then your right.

Anyways, I agree with what the others said about the pith.
Mobile Demension sawmill, Bobcat 873 loader, 3 dry kilns and a long "to do" list.

beenthere

The warpage is a result of the larger greater shrinkage of the wood along the annual ring, than across the ring. As you will see, the ring just outside the pith controls the flatness of the board.
Rip it down through the pith, joint the two edges, and edge glue them back together after flipping one end for end . Run it through the planer and you have a usable board. Other trimming around other defects necessary to suit your taste.  :)
south central Wisconsin
It may be that my sole purpose in life is simply to serve as a warning to others

bedway

Ive salvaged and used a lot of wood that was considered bad because one or more sections of a board had a defect. Over the years ive gotton quite good at cutting out the so called bad areas and  flipping the grain and glueing wood back together. :D  A 12 inch board that has been compiled from several smaller pieces being glued together is normally more stable ,,,in my experience,,,bedway

Joel Eisner

It looks like you could cut some nice face frame material for cabinetry.
The saga of our timberframe experience continues at boothemountain.blogspot.com.

Max sawdust

What everyone said!
I get that all the time when quarter sawing Red Oak, because I am trying to keep the blade in that pith :)
The board with the pith will crack and warp.  Even with air drying you will get that.  I dry them with the pith, then saw out the "flat sawn" center and end up with 2 nice vertical grain quarter sawn pieces. You can even slip match the pieces so they look like one board when put back together!   No way would I make a 4x4 out of a premium species just to avoid this.
Max
True Timbers
Cedar Products-Log & Timber Frame Building-Milling-Positive Impact Forestscaping-Cut to Order Lumber

Left Coast Chris

Some strategies I use to minimize boards with heart center are:

1)  After the board comes off the mill, set it in a seperate pile for riping with the skill saw or resaw with the mill.  Cutting the heart center out or putting it on the edge of the board usually does the trick.

2)  Prior to cutting the log, measure the distance from the heart center to the bed of the mill on each end of the log.  Carefully level the log to get the distances the same so you minimize how many boards that have heart center.   If the log is big enough and you do not want to take the time to resaw the boards with heart center then attempt to get a cut as close to the center as possible.  This will put the center at the edges of the borads.

As for the checks.......... sometimes they are unavoidable but another cause is internal log damage when falling or handling.  Ian would have to explain some techniques to minimize impact with the ground or other logs when falling.   

Good sawing though!  We all end up with some cupped boards for salvage. :) :) :)
Home built cantilever head, 24 HP honda mill, Case 580D, MF 135 and one Squirel Dog Jack Russel Mix -- Crickett

Engineer

I sawed enough QS cherry out of boards like that to make the face frames for my entire kitchen.  The pith goes in the wood boiler to heat the house.  No waste.

solidwoods

Cherry can only be air dried in a properly set up drying shed.  It wont stand to be outside with the wild wind blowing up its,';,,,, at all (also Oaks, hickory, and on and on).
The rate that moisture is removed must be controlled (after you know average/highest/lowest  mc).

The pics do show that each slice of a log is used for a different purpose, and the effects of drying the wood to fast.

I use the pith slice or slices for narrow qtr sawn pieces.  The slice is narrow but the flecks are biggest/wildest at the tree center.

jim











Ret. US Army
Kasco II B Band mill
Woodworking since 83
I mill & kiln dry lumber, build custom furniture, artworks, flooring, etc.
If you mill, you'll be interested in some of my work in one way or another.
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N. Central TN.

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