I have a number of two year old 8"x8' red oak planks that were
rough-cut straight but have warped laterally about 4 inches. There's
no cupping, just bent like a banana. The oak tree this wood came from
was leaning over a boathouse on the river and the owner had the tree
cut down. The warping is apparently due to unrelieved lenghtwise
stress in the wood that came out during the drying.
My question is how can I trim the boards lengthwise straight to get
the first side straight? If I put the convex side against the fence on
a table saw, there'll be only one point of contact which will cause
the board to wobble. If I put the concave side against the fence, the
two points of contact will be constantly changing as the trailing
curved part of the board comes in contact with the fence (the distance
between the curved inside edge of the board and the fence will be
constantly changing).
The only thing I can think of is to snap a chalk line along one side
and hand feed the plank through a bandsaw, but that would still not
give me a true flush side.
Any help would be appreciated.
William
On Sat, 13 Dec 2003 21:10:03 GMT, [email protected] (Doug Miller)
wrote:
>The best use for this wood is in a fireplace or wood stove (as fuel, not as
>trim around it).
Why not use it for chair backs ? Saves steaming it to shape.
If "knees" are good enough for boatbuilding, why not chairs ?
--
What ? Me ? Evil Dictator of Iraq ?
Nah mate, I'm just a Hobbit, honest
In article <[email protected]>, [email protected] (William) wrote:
>I have a number of two year old 8"x8' red oak planks that were
>rough-cut straight but have warped laterally about 4 inches. There's
>no cupping, just bent like a banana. The oak tree this wood came from
>was leaning over a boathouse on the river and the owner had the tree
>cut down. The warping is apparently due to unrelieved lenghtwise
>stress in the wood that came out during the drying.
Correct diagnosis.
The best use for this wood is in a fireplace or wood stove (as fuel, not as
trim around it). No matter what method you use for making straight boards from
this lumber, there will still be internal stresses that will be partially
relieved by removal of some wood, and the boards will crook again. And
again. Further, if you do manage to get more-or-less straight boards out of
these, the grain won't be parallel to the edges either (which gives an
undesirable appearance).
This tree should never have been sawn for lumber. It should have been cut into
18" lengths and quartered with an axe.
If you're determined to use it as lumber anyway, read on...
>
>My question is how can I trim the boards lengthwise straight to get
>the first side straight? If I put the convex side against the fence on
>a table saw, there'll be only one point of contact which will cause
>the board to wobble. If I put the concave side against the fence, the
>two points of contact will be constantly changing as the trailing
>curved part of the board comes in contact with the fence (the distance
>between the curved inside edge of the board and the fence will be
>constantly changing).
Correct on all counts. The latter approach is the typical one when dealing
with slightly crooked stock, but it won't work for a crook of the magnitude
you're describing.
>
>The only thing I can think of is to snap a chalk line along one side
>and hand feed the plank through a bandsaw, but that would still not
>give me a true flush side.
Close enough, though, that you can use that side as a reference surface
against the tablesaw fence or on a jointer. Or you can bandsaw it as you
describe, and then handplane it straight.
>Any help would be appreciated.
If you don't need the full 8' of length in a single board, cut them shorter
first and then straighten them using any of the methods you suggested above.
That will substantially increase the yield, and substantially reduce the
magnitude of later changes in shape.
I still think this wood is best off in a fireplace, though.
--
Doug Miller (alphageek at milmac dot com)
How come we choose from just two people to run for president and 50 for Miss America?
> "John Grossbohlin" <[email protected]> wrote in message news:<[email protected]>...
> >"William" <[email protected]> wrote in message
> news:[email protected]...
> > I have a number of two year old 8"x8' red oak planks that were
> > rough-cut straight but have warped laterally about 4 inches. There's
> > no cupping, just bent like a banana...
> >
> > The only thing I can think of is to snap a chalk line along one side
> > and hand feed the plank through a bandsaw, but that would still not
> > give me a true flush side.
> I'd be inclined to cut it into shorter lengths and straighten an edge on the
> jointer. It's nice to have 8' lengths but with tension wood it is likely to
> move around a lot indefinitely. Cut into shorter lengths and used for
> smaller projects would likely yield better results.
That's what I decided to do. That way the curvature is minimal on each
section. I wouldn't have used this wood as you and Doug Miller
mentioned except that it's a small project "for my eyes only" and the
wood is what's available.
> On the other hand, if you are determined to use the 8' lengths and have a 6"
> or 8" jointer, do as you suggest, then rip the opposite edge on the table
> saw. At this point don't worry if both edges are perfect... you're just
> trying to get it straight enough and narrow enough for the next steps. The
> next step is to face joint one side, thickness plane, then edge joint one
> edge, then rip the other edge on the table saw and finish the sawn edge by
> taking a light pass on the jointer. Now that it is straight, flat, and
> dimensioned, glue it to a 1/8" or 1/4" steel plate with epoxy to keep it
> that way. ;-) Seriously, it is unlikely to stay that way at 8'...
>
> John
I do like overkill. A 1/4" steel plate behind each piece is a nice
touch. After factoring in the cost of buying the steel and having it
cut to size, I could probably buy 1000 board feet of straight red oak
for the same price. But I do like the way you think! :)
Thanks to all for your replies.
Regards,
William
Check out the Joint'R Clamp.
Woodcraft sells em
Product number: 15J50
"William" <[email protected]> wrote in message
news:[email protected]...
> I have a number of two year old 8"x8' red oak planks that were
> rough-cut straight but have warped laterally about 4 inches. There's
> no cupping, just bent like a banana. The oak tree this wood came from
> was leaning over a boathouse on the river and the owner had the tree
> cut down. The warping is apparently due to unrelieved lenghtwise
> stress in the wood that came out during the drying.
>
> My question is how can I trim the boards lengthwise straight to get
> the first side straight? If I put the convex side against the fence on
> a table saw, there'll be only one point of contact which will cause
> the board to wobble. If I put the concave side against the fence, the
> two points of contact will be constantly changing as the trailing
> curved part of the board comes in contact with the fence (the distance
> between the curved inside edge of the board and the fence will be
> constantly changing).
>
> The only thing I can think of is to snap a chalk line along one side
> and hand feed the plank through a bandsaw, but that would still not
> give me a true flush side.
>
> Any help would be appreciated.
>
>
> William
"William" <[email protected]> wrote in message
news:[email protected]...
> I have a number of two year old 8"x8' red oak planks that were
> rough-cut straight but have warped laterally about 4 inches. There's
> no cupping, just bent like a banana. The oak tree this wood came from
snip
> The only thing I can think of is to snap a chalk line along one side
> and hand feed the plank through a bandsaw, but that would still not
> give me a true flush side.
I'd be inclined to cut it into shorter lengths and straighten an edge on the
jointer. It's nice to have 8' lengths but with tension wood it is likely to
move around a lot indefinitely. Cut into shorter lengths and used for
smaller projects would likely yield better results.
On the other hand, if you are determined to use the 8' lengths and have a 6"
or 8" jointer, do as you suggest, then rip the opposite edge on the table
saw. At this point don't worry if both edges are perfect... you're just
trying to get it straight enough and narrow enough for the next steps. The
next step is to face joint one side, thickness plane, then edge joint one
edge, then rip the other edge on the table saw and finish the sawn edge by
taking a light pass on the jointer. Now that it is straight, flat, and
dimensioned, glue it to a 1/8" or 1/4" steel plate with epoxy to keep it
that way. ;-) Seriously, it is unlikely to stay that way at 8'...
John
[email protected] (William) writes:
[...]
> My question is how can I trim the boards lengthwise straight to get
> the first side straight? If I put the convex side against the fence on
Attach somehow to a straight board/post, and run that post against the
tablesaw fence. This way you have a straight side to run against the fence.
--
Dr. Juergen Hannappel http://lisa2.physik.uni-bonn.de/~hannappe
mailto:[email protected] Phone: +49 228 73 2447 FAX ... 7869
Physikalisches Institut der Uni Bonn Nussallee 12, D-53115 Bonn, Germany
CERN: Phone: +412276 76461 Fax: ..77930 Bat. 892-R-A13 CH-1211 Geneve 23