My MIL had a friend with an heirloom crocheted wall hanging that had un-raveled. She asked if I could fix it. I was so intimidated after doing a Google search for instructions that I set it aside and forgot about it. Shame on me. Recently stumbled across it and decided that I felt bad enough to just try to fix it right.
Essentially, if anyone stumbles across this post looking for instructions on repairing crochet doilies and/or wall hangings, what I would say is just try. It can't hurt - the hanging was useless as it was. Also, you have to give up on perfection. I couldn't even mimic my own tension and style, let alone someone else's tension and crochet style. So just jump in. I started by un-raveling enough to be certain I'd found all the loose ends. It wouldn't do any good to repair if the piece came apart again. This took courage as I ultimately had to "cut" more thread off - you can't crochet with 3 inches of thread which is tangled because it's been like this for ages. Next, I tried to knot each loose end at an appropriately strong point - mostly at the double crochet points. Then it was a matter of tying on to the lowest point for repair - weaving my own loose ends and trying my best to minim to the tension and crochet style of the original. This was probably the most challenging for me because I use a significantly tighter tension. I ultimately ripped my own work out and re-crocheted sections multiple times. As I joined to the existing portion on each side I did a liberal amount of slip stitches to "climb" to the next row, again, trying to hide the knots I had to make on the loose ends.
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The repair spans the entire width of the "A" in "Came", pictured above. On the right, you can clearly see the heavy double crochets where I tied on. On the left, towards the top, you can see my error - adding a gap where one should not be as I joined to the original. I didn't realize this error until I was all fixed and I was too scared that I might do more damage fixing my error that everyone might not see.
I hope the owner is not disappointed. I'm pleased as punch to have fixed such a lovely work of art.