Fix this warp help.

Re: Fix this warp help.

john lucas

>There are two possibilities. one is to wet the concave side. This swells the wood and makes this side want to stretch which makes it straighten out. I've had some success straightening warped table leaves this way.

The other would be to steam bend it. I've done a little cherry and it was green to start with. You'll have to guess at how much spring back to allow for so you'll need to make the form curve in the opposite direction a little. You can make a good steam box out of PVC pipe or just build a wooden box. There was a good article on steam bending in the latest issue of Woodmagazine. They did it like I do with a steam kettle. I run a piece of hose from the nozzle to the PVC pipe and use a small electric burner to produce the heat.

There is a 3rd solution. These legs will be maybe 16 to 18 inches apart. Do you think anyone but you will notice? If not proceed with the construction. If you think they will then look at my first two suggestion.

Re: Fix this warp help.

Don Evans

>Well, John is right in how it can be done, but I fear they would only be temporary with this particular piece off wood.

Note the grain in the side of the piece, no matter what you do it will always try to return to where it is now.

If you are building a rocker to last many years, you'll be time and pride ahead to find another piece of wood for the chair.

Save and use smaller cuts of this piece for something else.

Don

Re: Fix this warp help.

Dave Mount

>Depends on why the pieces moved. Sometimes pieces like this spring because of internal stresses that developed during the original drying. That tension will not be correctable short of steam bending. By doing that, you basically make the wood fibers plastic enough to slip and relieve the stress. The bad news here is, besides the effort to build a steamer big enough to do the job, is that you will likely have to overbend the other direction to allow for some springback, and the likelihood that you will end up at dead straight is slim (better probably, but not dead straight). On the other hand, in this app, a little bow probably won't be noticeable.

On the other hand, if the pieces moved because they were not equilibrated with their new environment, which is not unusual during the heating season and with thick stock, then the bend may be at least partially correctable. Clamp the pieces together so their concave faces are together and clamp them tightly enough to bring those faces together. Then move the whole business to your heated room and leave it for a week. Unclamp them and see if you've made any progress. When/if you get them to close to straight, unclamp them and insert some small spacers (e.g., short pieces of 3/4x3/4 stock) along the length every 12" or so and reclamp them together, now presumably close to straight but held apart so air can circulate to the inside faces. Leave it another week in the heated space and see where you're at.

The idea behind this is the possibility that there was a moisture gradient in the pieces you milled. If so, the wood will move to the dry side when you remove the other side of the stock which was counteracting it. By clamping the pieces together initially, you don't straighten them with clamping per say, but you slow moisture transfer on the already too dry faces by removing their contact with the air, and you encourage it on the too moist (convex) faces. The second step is to let everything come to equilibrium with the ambient air so there isn't a significant moisture differential. Might or might not work, hard to say.

If it does work, when you move the pieces back to your shop (presumably higher relative humidity from your description), store the pieces clamped with the stickers as above so they reacclimate evenly.

Good luck,

Dave

Re: Fix this warp help.

john lucas

>Good thought Dave. I agree with the equilibrium concept as a possibility.

Brilliant idea!

DeanG

>Using such a method would never have occurred to me, but now I`ll be able to remember it should I ever need it. Thanks!