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Jim H
10-28-2003, 04:41 PM
What is grain run-out? I thought it was what I saw in the planking on the boat posted by HS in the Turkey thread.
http://users.tpg.com.au/imp517/fethiye/fethiye_3.jpg

The shear plank (at the bow)on this boat shows , what I thought to be, grain run-out, that oval pattern. Anyone have an example?

Jim H
10-28-2003, 04:41 PM
What is grain run-out? I thought it was what I saw in the planking on the boat posted by HS in the Turkey thread.
http://users.tpg.com.au/imp517/fethiye/fethiye_3.jpg

The shear plank (at the bow)on this boat shows , what I thought to be, grain run-out, that oval pattern. Anyone have an example?

Jim H
10-28-2003, 04:41 PM
What is grain run-out? I thought it was what I saw in the planking on the boat posted by HS in the Turkey thread.
http://users.tpg.com.au/imp517/fethiye/fethiye_3.jpg

The shear plank (at the bow)on this boat shows , what I thought to be, grain run-out, that oval pattern. Anyone have an example?

Bob Smalser
10-28-2003, 05:11 PM
Not quite in the typical use of the term.

You're merely looking at cone-shaped growth rings sliced on a flat plane...."flatsawn" boards....in a sense, that is "grain runout" when cut by most mills...but in the third dimension or thickness.

"Grain runout" is when the board ain't cut true to the log along it's length (or thickness in the less-common case of twist) for whatever reason...the growth rings (really cones when looking at them in three dimensions) disappear off the edge of the board along it's long dimension rather than run the full length of it.

Crooked or twisted log growth, drunk or blind sawyers...all contribute. Any tapered log cut into a cant will have some runout over a flatsawn board's thickness or a flitchcut board's edge until you get close to the pith. That's why riven boards are superior in strength for their size and some modern mills are made to cut from bark-to-bark w/o having to make a cant first...the waste or excess because of the log's taper taken out at the pith....which is the worst wood in the log usually relegated to thick stock.

The board-grading criteria includes the percentage of grain runout allowed.

When not obvious, you test for grain runout by running a dull awl down the grain so it catches and follows it....or touch a Magic Marker to the wood and watch which direction the ink seeps toward.

Or, you can use my more scientific method....when milling twisty Madrone logs into stair treads I whack each board real hard on the edge of the stack before I place it on the stickers...if it breaks, it goes into the pile for blocking.

[ 10-28-2003, 05:18 PM: Message edited by: Bob Smalser ]

Bob Smalser
10-28-2003, 05:11 PM
Not quite in the typical use of the term.

You're merely looking at cone-shaped growth rings sliced on a flat plane...."flatsawn" boards....in a sense, that is "grain runout" when cut by most mills...but in the third dimension or thickness.

"Grain runout" is when the board ain't cut true to the log along it's length (or thickness in the less-common case of twist) for whatever reason...the growth rings (really cones when looking at them in three dimensions) disappear off the edge of the board along it's long dimension rather than run the full length of it.

Crooked or twisted log growth, drunk or blind sawyers...all contribute. Any tapered log cut into a cant will have some runout over a flatsawn board's thickness or a flitchcut board's edge until you get close to the pith. That's why riven boards are superior in strength for their size and some modern mills are made to cut from bark-to-bark w/o having to make a cant first...the waste or excess because of the log's taper taken out at the pith....which is the worst wood in the log usually relegated to thick stock.

The board-grading criteria includes the percentage of grain runout allowed.

When not obvious, you test for grain runout by running a dull awl down the grain so it catches and follows it....or touch a Magic Marker to the wood and watch which direction the ink seeps toward.

Or, you can use my more scientific method....when milling twisty Madrone logs into stair treads I whack each board real hard on the edge of the stack before I place it on the stickers...if it breaks, it goes into the pile for blocking.

[ 10-28-2003, 05:18 PM: Message edited by: Bob Smalser ]

Bob Smalser
10-28-2003, 05:11 PM
Not quite in the typical use of the term.

You're merely looking at cone-shaped growth rings sliced on a flat plane...."flatsawn" boards....in a sense, that is "grain runout" when cut by most mills...but in the third dimension or thickness.

"Grain runout" is when the board ain't cut true to the log along it's length (or thickness in the less-common case of twist) for whatever reason...the growth rings (really cones when looking at them in three dimensions) disappear off the edge of the board along it's long dimension rather than run the full length of it.

Crooked or twisted log growth, drunk or blind sawyers...all contribute. Any tapered log cut into a cant will have some runout over a flatsawn board's thickness or a flitchcut board's edge until you get close to the pith. That's why riven boards are superior in strength for their size and some modern mills are made to cut from bark-to-bark w/o having to make a cant first...the waste or excess because of the log's taper taken out at the pith....which is the worst wood in the log usually relegated to thick stock.

The board-grading criteria includes the percentage of grain runout allowed.

When not obvious, you test for grain runout by running a dull awl down the grain so it catches and follows it....or touch a Magic Marker to the wood and watch which direction the ink seeps toward.

Or, you can use my more scientific method....when milling twisty Madrone logs into stair treads I whack each board real hard on the edge of the stack before I place it on the stickers...if it breaks, it goes into the pile for blocking.

[ 10-28-2003, 05:18 PM: Message edited by: Bob Smalser ]

Jim H
10-28-2003, 05:28 PM
Bob, thanks that makes sense.

Jim H
10-28-2003, 05:28 PM
Bob, thanks that makes sense.

Jim H
10-28-2003, 05:28 PM
Bob, thanks that makes sense.

Bob Smalser
10-28-2003, 11:38 PM
Oh...forgot...that oval grain shape in that flatsawn port sheerstrake near the stem was a crook or bump in the log that was sliced off in milling the board.

And notice it's mate on the starboard sheer was cut just above it....closer to the bark side of the log.

[ 10-28-2003, 11:40 PM: Message edited by: Bob Smalser ]

Bob Smalser
10-28-2003, 11:38 PM
Oh...forgot...that oval grain shape in that flatsawn port sheerstrake near the stem was a crook or bump in the log that was sliced off in milling the board.

And notice it's mate on the starboard sheer was cut just above it....closer to the bark side of the log.

[ 10-28-2003, 11:40 PM: Message edited by: Bob Smalser ]

Bob Smalser
10-28-2003, 11:38 PM
Oh...forgot...that oval grain shape in that flatsawn port sheerstrake near the stem was a crook or bump in the log that was sliced off in milling the board.

And notice it's mate on the starboard sheer was cut just above it....closer to the bark side of the log.

[ 10-28-2003, 11:40 PM: Message edited by: Bob Smalser ]

NormMessinger
10-29-2003, 08:27 AM
Nice. I hope they finished those two beautiful boards bright.

NormMessinger
10-29-2003, 08:27 AM
Nice. I hope they finished those two beautiful boards bright.

NormMessinger
10-29-2003, 08:27 AM
Nice. I hope they finished those two beautiful boards bright.

Bruce Hooke
10-29-2003, 11:48 AM
Here's a nice picture that illustrates grain runout:

http://www.frets.com/FRETSPages/General/Glossary/Runout/RunoutViews/runout7.jpg

It's from this website, which discusses the topic in detail (from the perspective of a guitar builder):

http://www.frets.com/FRETSPages/General/Glossary/Runout/runout.html

I would argue that grain runout could look pretty similar to the picture at the start of this thread, but the amount of runout on such a board would be quite small. However, in looking for grain runout it is best to look at the face (or edge) of the board that the growth rings are closest to perpendicular to. The face of the board that the grain is parallel to (such as in the top strake on the boat shown) can show quite "wild" grain even when there is very little runout and so can be quite misleading.

Boards that show runout on the narrow edges (which means they would be flat-sawn boards) are generally much more of an issue than quartersawn boards with runout on the faces, because the width of the board will reduce the impact of the runout on the quartersawn board.

Bruce Hooke
10-29-2003, 11:48 AM
Here's a nice picture that illustrates grain runout:

http://www.frets.com/FRETSPages/General/Glossary/Runout/RunoutViews/runout7.jpg

It's from this website, which discusses the topic in detail (from the perspective of a guitar builder):

http://www.frets.com/FRETSPages/General/Glossary/Runout/runout.html

I would argue that grain runout could look pretty similar to the picture at the start of this thread, but the amount of runout on such a board would be quite small. However, in looking for grain runout it is best to look at the face (or edge) of the board that the growth rings are closest to perpendicular to. The face of the board that the grain is parallel to (such as in the top strake on the boat shown) can show quite "wild" grain even when there is very little runout and so can be quite misleading.

Boards that show runout on the narrow edges (which means they would be flat-sawn boards) are generally much more of an issue than quartersawn boards with runout on the faces, because the width of the board will reduce the impact of the runout on the quartersawn board.

Bruce Hooke
10-29-2003, 11:48 AM
Here's a nice picture that illustrates grain runout:

http://www.frets.com/FRETSPages/General/Glossary/Runout/RunoutViews/runout7.jpg

It's from this website, which discusses the topic in detail (from the perspective of a guitar builder):

http://www.frets.com/FRETSPages/General/Glossary/Runout/runout.html

I would argue that grain runout could look pretty similar to the picture at the start of this thread, but the amount of runout on such a board would be quite small. However, in looking for grain runout it is best to look at the face (or edge) of the board that the growth rings are closest to perpendicular to. The face of the board that the grain is parallel to (such as in the top strake on the boat shown) can show quite "wild" grain even when there is very little runout and so can be quite misleading.

Boards that show runout on the narrow edges (which means they would be flat-sawn boards) are generally much more of an issue than quartersawn boards with runout on the faces, because the width of the board will reduce the impact of the runout on the quartersawn board.

Stephen Hutchins
10-29-2003, 12:20 PM
When bending wood with grain run out or knots, bend it so the grain run out (or knot)is on the inside of the bend. You'll break alot less wood this way. This technique works well with frames and planks- especially northern white cedar. Sometimes when I was building I couldn't avoid putting run out on the outside of the bend and was still able to keep the wood in one piece by backing up the outside of the bend with another piece of wood. (Old news I know for most here but someone will benifit I hope.)

Stephen Hutchins
10-29-2003, 12:20 PM
When bending wood with grain run out or knots, bend it so the grain run out (or knot)is on the inside of the bend. You'll break alot less wood this way. This technique works well with frames and planks- especially northern white cedar. Sometimes when I was building I couldn't avoid putting run out on the outside of the bend and was still able to keep the wood in one piece by backing up the outside of the bend with another piece of wood. (Old news I know for most here but someone will benifit I hope.)

Stephen Hutchins
10-29-2003, 12:20 PM
When bending wood with grain run out or knots, bend it so the grain run out (or knot)is on the inside of the bend. You'll break alot less wood this way. This technique works well with frames and planks- especially northern white cedar. Sometimes when I was building I couldn't avoid putting run out on the outside of the bend and was still able to keep the wood in one piece by backing up the outside of the bend with another piece of wood. (Old news I know for most here but someone will benifit I hope.)