Dap 12278 Elastopatch Pro Grade Elastomeric Patching Compound, 32 Oz.

Have been using this product for 40 years. In Ft. Laud. we used it mainly for stucco and concrete repairs. It lasted over 20 yrs on some of the jobs. Use it here in Jacksonville for wood repair. Big holes small holes cracks-makes no difference. Use membrane if crack or hole is too big.

Used this for many hairline cracks in old plaster wall and some cracks up to 1/8th of an inch - in cases where the plaster is still attached to the lath (meaning it does not move in when you push the wall). The product works very well for these kinds of cracks. Be sure to follow the instructions carefully. It has 10 minutes of tooling time, and it gets hard to work after 10 minutes. Just use small batches. There’s a good This Old House video on plaster crack repair that shows well how to use this stuff. A tip: the textured version is just a little easier to work with than the smooth, so if you find you are not a trowel artist, you might start with that.