Warped wood

This message is posted on behalf of Rogier Smelt.

    I have recently been investigating methods of straightening
    warped timbers and came across a response to a question posted
    in the DistList archives in CoOL, entitled 'Water damage to wood
    floors'.

    The problem that I am faced with involves the warped sides of a
    Seaweed Marquetry Longcase clock. In most cases a slight cupping
    is usually acceptable, however with this particular example, the
    movement is so extreme that is has distorted the aperture that
    houses the door thus rendering the locking mechanism
    dis-functional.

    The substrate of the sides is oak with cross-grained walnut
    veneer on the external areas, this has resulted in different
    coefficients of expansion and contraction between these
    surfaces.

    I am aware that many processes have been used in the past ie:
    the introduction of moisture, heat, PEG etc into the timber or
    even the use of non-hydroscopic 'sealers' to trap moisture
    within the cells of the timber. On certain occasions more
    interventive mechanical methods have been employed in the past.

    To date I have chosen the caution approach and opted to use
    moisture. This I have done by laying strips of fabric along the
    length of each internal surface and introducing water to this
    material. Periodically I have heated the damp fabric locally to
    produce steam. The result was successful and the surface was
    allowed to dry naturally. However, as the moisture evaporated
    from the substrate the timber recovered to its original form.

    Finally, time is now a constraint because the job has to be
    completed within 4 weeks. I would be grateful for any advice.
    Many thanks.

    Rogier Smelt.
    Student of West Dean College, England

                                  ***
                  Conservation DistList Instance 13:2
                   Distributed: Monday, June 21, 1999
                        Message Id: cdl-13-2-011
                                  ***