I just received an oil painting that was not packaged/rolled securely and folded/compressed during transport. Now it has creases. Is there any way to remove these without damaging the painting?
Stretching it properly on the right sized frame should be enough to remove the creases, no water required. Properly is:
- Procuring a support of the right dimensions. The original frame on which the work was painted would be the best.
- Centering the painting on the support, and tacking (stapling) the work to the frame at the midpoint of each edge. This will be on the back of the work so put something on the table to protect the painting. Or, more challenging, do not place flat on table at all instead keeping in on the edge of the frame and only resting on the unworked edge of the painting under it on that side.
- Stretch and tack (staple) the painting outward from the centers balancing the tension by working one center to edge, then the opposite side center to edge, and so on...
It may require some force to get the right tension but do not use too much or you will twist the frame. When stretching raw canvas water does help loosen the fibers and will dry much tighter and smoother. However it would be best to avoid water of any type on the finished piece. It could cause damage possibly staining the work, separating the paint from the canvas, encouraging mold and so on.
You should stretch it on a frame. That way, in time, it will readjust itself.
Do not force the stretching (which is something the word 'stretching' implies). Allow the canvas to flatten itself.
With heavy creases you might have to stretch the canvas several times for all wrinkles to disappear. Be patient.
A completely safe and archival way (no force involved), is to mount the artwork on a vacuum table:
Snapshot from video by Baumgartner Restoration
On the table it can be sealed in, and while the table (if desired) warms up the canvas in a controlled way (usually in combination with heat-activated archival adhesives), the air will get sucked out from the envelope, allowing the user to smooth out remaining creases and wrinkles.
Obviously, a vacuum or hot table is not something everyone has access to, but I'm mentioning it since it seems the safest and most effective option.