How to mend a Picasso painting.

By Aussiegirl

For those of my readers who may be worrying about their own Picassos, here is an interesting article on how to repair a painting. As far as I'm concerned, though, you could set fire to this ugly thing, after first jumping up and down on it with dirty shoes. Believe me, if this monstrosity had turned up in an auction house with "Capisso", rather than "Picasso", as the name of the artist, it would have been hurled out the door!
(Here is some information about this "thing" that I found elsewhere: The Spanish artist's famous "The Dream" turned into a nightmare for Las Vegas casino magnate Steve Wynn when he accidentally put his elbow through the 1932 portrait of Picasso's mistress Marie-Therese Walter.)

How to mend a Picasso painting. - By Daniel Engber - Slate Magazine

I Punched a Hole in My Picasso!
Now what do I do?
By Daniel Engber

Casino mogul Steve Wynn ripped a hole through his $139 million Picasso painting while gesticulating at a cocktail party, reports the New York Post. Nora Ephron gave her own first-person account of the damage: It was "a black hole the size of a silver dollar … with two three-inch long rips coming off it in either direction." Wynn had just agreed to sell the painting; now, the deal is off. Is there any way to fix the ripped Picasso?

Yes, but it will be slow and tedious work. The torn ends of the canvas can probably be lined up, and conservators can identify matching fibers on either side of the rip by inspecting them under a microscope. In general, you can expect the wefts in the fabric—that is, the crosswise yarns of the weave—to split at the site of the impact. The lengthwise warps tend to get stretched out, but they may not break.

The rip itself can be mended in a few different ways. First, the conservator can line up the torn ends and affix them to a new piece of fabric that lines the back of the painting. She might also try to attach the torn ends to each other using a method called Rissverklebung, in which individual fibers are rewoven back into place.

To reweave the warps and wefts, you have to figure out the proper placement of each individual fiber. Bits of paint that are stuck to the fibers must be glued in place or removed until the reweaving is complete. (Conservators map out the location of each paint flake they remove so it can be replaced in precisely the right spot.) Because an accident will stretch out some fibers and fray others, you sometimes have to tie off and shorten some threads while attaching new material to lengthen others. Threads attached to the back of the canvas will reinforce the seam.

Closing the tear is only the first part of the process. An accident like Wynn's can damage the painting in other places by stretching the fabric and distorting the image. To correct for these planar distortions, the conservators try to change the lengths of individual fibers or small patches of the canvas. Applied humidity can make a fiber expand across its diameter and shrink across its length—and tighten up distended parts of the weave.

Bits of paint that have fallen off the painting must also be replaced. Wynn might have surveyed the scene of the accident and saved any stray bits of paint for the conservators in a petri dish. (Chance are he didn't strip much off the canvas—Ephron says he was wearing a golf shirt, which suggests a bare-elbow blow. An elbow covered with rough fabric would probably have done more damage.) Conservators have to touch up spots of missing paint with fresh material, color-matched to the surrounding area.

One more thing: Conservators always try to make their repairs reversible. That way, you won't cause any permanent damage to the work if you screw up, and someone can always try to improve on your work in the future.