I have a fence which I would like to raise by 1ft. The posts are 4×4'' pressure treated wood. I would like to cut a new 4×4 post into 1ft pieces and put on top of existing ones.
What's the best way to attach the new 1ft pieces to the existing posts without the hardware used to hold it being visible? I saw a couple of neighbors used caps, angles or ties for that, but it visually sticks out — metal on wood is too much contrast.
Best Answer
Unless you stain or paint the fence, you will see the joint no matter what since the grain will not line up.
For this type of project I would recommend using a scarf joint.
This provides a much stronger connection than a simple butt joint. You get an increased glue area and the fastener geometry combined with the scarf will prevent the two pieces from bending apart. (You can use dowels or carriage bolts or screws. Dowels would be the least visible.)
A square scarf joint (as pictured) is pretty easy to make and very strong, but if you really want to hide the glue line as much as possible, you can make a diagonal joint.
That's a bit more work, though, especially if you have to do a lot of posts. The square scarf will tolerate a little less cutting precision as well.