Repairing a Warped Table Top

[astrid]

I have had success with this procedure.May sound drastic but it works. remove the top from its base,place it in a sheet of plastic,outside with the bottom of the table top facing up (the finished side to the plastic) and leave it for several days or until the top has corrected.Once level, coat the bottom with a sealer and secure it to the base.Remember do not glue it to the base,it must be able to move also when placing it outside be sure it is not in the sun but in a position where it can receive the morning dew and cover it if rain is expected.Good luck

what he said

astrid

[Cruzi]

From the picture the bottom side already has to much moisture, you need to dry it, not wet it. The strange way in which it has done so seems to have been caused by your fixing points, it has only allowed movement arcoss non-fixed areas.

To put it simply, the underside has been able to absorb more moisture than the finished topside which made it expand further than the top causing it to warp.

If you follow the suggested method of placing unsealed side in dew and/or rain your problem is going to get worse, not better.

Remove the top and place it unsealed side up in an airconditioned room.

It may take some time but since air-con removes a lot of moisture from the air it should flatten out, once flat then seal both faces.

If it doesn't flatten, unseasoned timber is your problem and drastic solutions are needed.

[Pinex]

Tried the leave outside method and found it cupped more but when dry came back to original cupped shape,I guess it had been warped for to long.Finished up breaking down join,planing and re-gluing,not perfect,but better than before,not as noticeable anyway.I am sure it would have worked on a recently warped piece of timber.Thanks for all the help.Martin

[Chipman]

Tried the leave outside method and found it cupped more but when dry came back to original cupped shape,I guess it had been warped for to long.Finished up breaking down join,planing and re-gluing,not perfect,but better than before,not as noticeable anyway.I am sure it would have worked on a recently warped piece of timber.Thanks for all the help.Martin

I think you have done the best thing.... Given it seems to have a twist (diagonally cupped across the grain) rather than a simple cup, there really was no other way. Post a pic when you are finished?

Chipman

[Pinex]

I have put in a pic. of the finished article.Hoping to put in two pics.before and after,I,ll see what happens.Martin

[Chipman]

Pinex, you have done an excellent job.... We will be coming to you for advice next time!

Cheers,

Chipman

[jhaiii]

Sorry for opening an ancient thread, but I came here looking for a solution but ended up trying something else using some of the suggestions for inspiration. Hopefully my suggestion will help others.

The idea is that warping is due to water being taken into the wood on one side more than another.
We need to get it out by drying in a non-humid environment. I live in Sydney which is really humid and caused my lovely homemade spotted gum outdoor table to warp significantly which I mistakenly only varnished on the top side. My table is quite large at 2400 x 950mm
I don't have access to a suitable air conditioned environment for drying so I came up with this:

1. buy 4kg of silica gel kitty litter ($6) (looks like white crystals like rock salt with blue chunks)
don't use any of the enviro/cat friendly natural options.
2. put in old pillow case
3. take table top off base and flip over
4. wrap entirely in clear plastic with kitty litter pillow case inside.
5. seal with duct tape so air tight (we don't want any fresh air inside)
6. leave outside in sun/heat (we had a week of 30C days). The position I had it only got the morning sun.
7. watch your table straighten out over a week in my case

The pillow case of kitty litter is effectively a huge one of those "DO NOT EAT" sachets that you find in shoe boxes and stuff.

In my case the table warped more on the first day which scared me, but then over the following days it straightened steadily. (I was measuring the curvature my measuring the depth of the 'cup' most days)

Out of interest I weighed my pillow case of kitty litter before and after.
- before: 3.782kg
- after 3.833kg
which essentially says that the silica gel took on 50g of moisture over 7 days.


Anyway, Hopefully this is useful to others...

[dr4g0nfly]

jhaiii,

That's an interesting concept, using a desiccant (the Kitty Litter) to extract the moisture.

I have some left over from the Sister-in-Laws Christmas stay (She brought her cat) and a freshly green turned small bowl. I can see an experiment coming on!

[jhaiii]

Dr4g0nfly, keen to hear the results of your experiment...