Epoxy is an ideal material that can be used to make permanent repairs on rotting window sills, door jambs, and rotted exterior molding etc. Typically the rotted exterior molding is difficult to remove and very expensive to replace. However, epoxy is very easy to handle and you can mix it like cookie dough, mold it like clay and use it to repair rotted surface. You can apply epoxy on rotted area and when it hardens you can carve and sand it just like wood.
Epoxy sticks well and can be formulated to flex and move with the wood. This is not going to crack and fall out like so other ordinary wood fillers.
Mentioned below are the steps how to use epoxy to repair rotted surface:
The first step is to find and prevent the cause of the rot. If you have located and corrected the cause of the rotted wood, you need to strip off the old paint and clean out all the decayed wood. You need to remember that old paint may contain lead and this is the reason why you need to use lead-safe paint removal techniques.
You should mix the epoxy by scooping two equal sized parts of the epoxy wood filler onto a scrap of hard paper or plywood. You need to mix the two parts of epoxy with a hard knife until they are completely blended. It is also important to shape the epoxy with your fingers and by handling it with a scrap of wood.
Once the epoxy is shaped properly, you can start filling the rotted wood. In order to check whether the epoxy is shaped properly, press it with your fingernail. If you can’t dent the epoxy with your fingernail, it is the ideal state to start filling. If the epoxy is hardened well, it is easy to shape and sand with standard wood repairing tools.You can use the epoxy filler to rough out the basic contour. While repairing the rotten wood, you need to follow the shape of the surrounding wood.
If you want a coarse filing material that is easier to apply on rotten wood, you can mix a little amount of consolidant with the epoxy. The consolidant helps you to make the filler consistent. Once you are done with the final sanding, rough up all hardened consolidant the surface.