I have just made a coffee table. The top is 1.5m x 0.55m, consisting
of three 1" pine boards glued edge-to-edge. I added some cross-brasing
underneath (glued + screwed).
The top is not fixed to the frame. It is designed so that it can be
lifted off.
Soon after assembly, the top has started to twist. Is there any remedy
for this? I am trying to correct the twist by laying the top on the
floor with a heavy weight on one end, and at the other end: a spacer
under the low corner and a weight on the high corner. That has
reversed the twist. But how long should I leave it with the weights in
place, and will it have any lasting effect?
Thanks for any advice.
Frank
Frank,
couple of questions:
1. Did you apply finish to both sides of the top?
2. When you prepared the top, did you sand and prepare only one surface?
3. Was the wood dry? ie kiln dried?
4. was the wood lying on one side for any period of time, particularly on
concrete?
5 Has it been in the sun?
Your answers may help to determine what the underlying cause is.
Greg
"Frank Watson" <[email protected]> wrote in message
news:[email protected]...
>
> I have just made a coffee table. The top is 1.5m x 0.55m, consisting
> of three 1" pine boards glued edge-to-edge. I added some cross-brasing
> underneath (glued + screwed).
>
> The top is not fixed to the frame. It is designed so that it can be
> lifted off.
>
> Soon after assembly, the top has started to twist. Is there any remedy
> for this? I am trying to correct the twist by laying the top on the
> floor with a heavy weight on one end, and at the other end: a spacer
> under the low corner and a weight on the high corner. That has
> reversed the twist. But how long should I leave it with the weights in
> place, and will it have any lasting effect?
>
> Thanks for any advice.
>
> Frank
I personally do not think all this stuff about laying it in the sun, weight
etc will work the comment about finishing both sides is though, it allows
equal absobtion of moisture .
My suggestion is to remove the x grain battans and put one diagonally that
is slightly convex so that it will pull the opposite corners down . It will
be a trial and error effort regarding how much covexisity [?] is needed
,keep trying clamp the ends each time until the twist is gone then remove
the clamps and use screws to attach the end of the batten to the top ....mjh
--
mike hide
"Frank Watson" <[email protected]> wrote in message
news:[email protected]...
>
> I have just made a coffee table. The top is 1.5m x 0.55m, consisting
> of three 1" pine boards glued edge-to-edge. I added some cross-brasing
> underneath (glued + screwed).
>
> The top is not fixed to the frame. It is designed so that it can be
> lifted off.
>
> Soon after assembly, the top has started to twist. Is there any remedy
> for this? I am trying to correct the twist by laying the top on the
> floor with a heavy weight on one end, and at the other end: a spacer
> under the low corner and a weight on the high corner. That has
> reversed the twist. But how long should I leave it with the weights in
> place, and will it have any lasting effect?
>
> Thanks for any advice.
>
> Frank
On Thu, 04 Sep 2003 12:12:37 GMT, "Groggy" <[email protected]>
wrote:
>>1. Did you apply finish to both sides of the top?
Hi Greg - No - only one side.
>>2. When you prepared the top, did you sand and prepare only one surface?
The wood was so flat that I didn't do any preparing except with an
electric plane to make the joins flush - then a little bit of belt
sander sanding.
>>
>>3. Was the wood dry? ie kiln dried?
No - not terribly dry.
>>
>>4. was the wood lying on one side for any period of time, particularly on
>>concrete?
I dodn't know. It was stacked on end indoors when I bought it.
>>
>>5 Has it been in the sun?
I don't knw about before I bought it, but not since the twist started.
Frank
>>"Frank Watson" <[email protected]> wrote in message
>>news:[email protected]...
>>>
>>> I have just made a coffee table. The top is 1.5m x 0.55m, consisting
>>> of three 1" pine boards glued edge-to-edge. I added some cross-brasing
>>> underneath (glued + screwed).
>>>
>>> The top is not fixed to the frame. It is designed so that it can be
>>> lifted off.
>>>
>>> Soon after assembly, the top has started to twist. Is there any remedy
>>> for this? I am trying to correct the twist by laying the top on the
>>> floor with a heavy weight on one end, and at the other end: a spacer
>>> under the low corner and a weight on the high corner. That has
>>> reversed the twist. But how long should I leave it with the weights in
>>> place, and will it have any lasting effect?
>>>
>>> Thanks for any advice.
>>>
>>> Frank
>>
>>
On Thu, 04 Sep 2003 19:09:51 GMT, "Mike Hide" <[email protected]>
wrote:
>>I personally do not think all this stuff about laying it in the sun, weight
>>etc will work the comment about finishing both sides is though, it allows
>>equal absobtion of moisture .
>>
>>My suggestion is to remove the x grain battans and put one diagonally that
>>is slightly convex so that it will pull the opposite corners down . It will
>>be a trial and error effort regarding how much covexisity [?] is needed
>>,keep trying clamp the ends each time until the twist is gone then remove
>>the clamps and use screws to attach the end of the batten to the top ....mjh
Mike, that sounds like a workable plan - thank you!
Frank
On Thu, 04 Sep 2003 19:00:59 GMT, "Dave A." <[email protected]>
wrote:
>>How much twist?
The top is about 5ft x 2ft.when you lay in on a flat surface, with one
end weighted down, one of the far corners will rise off the ground
about 1" It's enough to be noticeable and irritating.
>>
>>Could be any of these or just bad luck. As for solutions...
>>
>>1. Your method may work or help
>>2. Remove support and rip back to 3 boards and replane flat and reglue
>>3. Take to a wide belt sander shop and pay someone to sand thinner
>>4. #3 with hand tools, plane, scraper, belt sander.
Greg - thanks for the suggestions. I'm not sure if I can face tthat
much effort though. If all else fails, I may just make a fresh top
using seasoned timber..
Frank
How much twist?
Could be any of these or just bad luck. As for solutions...
1. Your method may work or help
2. Remove support and rip back to 3 boards and replane flat and reglue
3. Take to a wide belt sander shop and pay someone to sand thinner
4. #3 with hand tools, plane, scraper, belt sander.
"Groggy" <[email protected]> wrote in message
news:[email protected]...
> Frank,
>
> couple of questions:
>
> 1. Did you apply finish to both sides of the top?
>
> 2. When you prepared the top, did you sand and prepare only one
surface?
>
> 3. Was the wood dry? ie kiln dried?
>
> 4. was the wood lying on one side for any period of time, particularly
on
> concrete?
>
> 5 Has it been in the sun?
>
> Your answers may help to determine what the underlying cause is.
>
> Greg
>
>
> "Frank Watson" <[email protected]> wrote in message
> news:[email protected]...
> >
> > I have just made a coffee table. The top is 1.5m x 0.55m, consisting
> > of three 1" pine boards glued edge-to-edge. I added some cross-brasing
> > underneath (glued + screwed).
> >
> > The top is not fixed to the frame. It is designed so that it can be
> > lifted off.
> >
> > Soon after assembly, the top has started to twist. Is there any remedy
> > for this? I am trying to correct the twist by laying the top on the
> > floor with a heavy weight on one end, and at the other end: a spacer
> > under the low corner and a weight on the high corner. That has
> > reversed the twist. But how long should I leave it with the weights in
> > place, and will it have any lasting effect?
> >
> > Thanks for any advice.
> >
> > Frank
>
>
I had a twisted pine board. The humity in my garage went from like 0% to
190% in a day. I brought it inside my house where the humity was normal and
I flattened it out with weights. It worked.
My understanding is that you need to finish wood on all sides. That doesnt
mean stain and stuff but at least seal with poly or whatever the finish is.
This makes it so water vapor is absorbed equally. I also believe that boards
expand lenghwise more than width wise so maybe your supports played a role
in the twist?
Sam
"Frank Watson" <[email protected]> wrote in message
news:[email protected]...
>
> I have just made a coffee table. The top is 1.5m x 0.55m, consisting
> of three 1" pine boards glued edge-to-edge. I added some cross-brasing
> underneath (glued + screwed).
>
> The top is not fixed to the frame. It is designed so that it can be
> lifted off.
>
> Soon after assembly, the top has started to twist. Is there any remedy
> for this? I am trying to correct the twist by laying the top on the
> floor with a heavy weight on one end, and at the other end: a spacer
> under the low corner and a weight on the high corner. That has
> reversed the twist. But how long should I leave it with the weights in
> place, and will it have any lasting effect?
>
> Thanks for any advice.
>
> Frank
Always a bummer when this happens. The weights will likely have little
to no effect. It can help sometimes when you get cupping across a gue
up that is do to tension at the joints but once the wood moves it is
very hard to undo it.
One possible "fix" is to bread board the ends, if you can live with
the look. This is how I would do it, following some of the rules to
allow for movement.
First create one big tenon across each end of the glue up. You might
have to make some strong feather borads or otherwise fanagle the glue
up through the router or table saw to rabbit it top and bottom.
Then trim the one big tenon to be one tenon on each board with about
an inch between each tenon.
Then, using a very flat board, 2-3" wide, make an end piece with a
single mortise all the way across stopping 1/2" from the end.
Flatten the glueup with weight or whatever and bang the new end piece
onto the tenons. Clamp it, drill it at the center of each board for a
peg. Knock it off and using a rattail file, slot the holes in the
tenons across the grain. Be careful not to oversize then in the other
direction or the new end board can pull away from the shoulder and
leave a gap.
Use yellow glue when you put it back together for good. It will
stretch enough during movement.
Finally (this won't help this time) I have been learning that glueups
are a lot more stable when I mill from rough stock myself. Also, Pine
is probably one of the worst for movement (that I have worked with).
They gorw and harvest this stuff so fast now it migght sprout leaves
if you spill water on it.
[email protected] (Frank Watson) wrote in message news:<[email protected]>...
> I have just made a coffee table. The top is 1.5m x 0.55m, consisting
> of three 1" pine boards glued edge-to-edge. I added some cross-brasing
> underneath (glued + screwed).
>
> The top is not fixed to the frame. It is designed so that it can be
> lifted off.
>
> Soon after assembly, the top has started to twist. Is there any remedy
> for this? I am trying to correct the twist by laying the top on the
> floor with a heavy weight on one end, and at the other end: a spacer
> under the low corner and a weight on the high corner. That has
> reversed the twist. But how long should I leave it with the weights in
> place, and will it have any lasting effect?
>
> Thanks for any advice.
>
> Frank