Incorporating live edge pieces into a project instantly gives it that hand-made, one-of-a-kind look. It shows a degree of control over the wild randomness of nature and brings the project to another level.
It’s relatively easy to take dimensional lumber from a store and make clean angled cuts which mate together seamlessly. However, most methods of measuring angles rely on the flat edges found on dimensional lumber. But how do we do this if we are using live edge material and do not have these perfectly planed edges to reference off of?
I do this through the use of a center line. A straight line connecting the center of each end of the slab provides a reliable reference from which angles can be accurately and repeatably measured. Of course, this is made easier if you have a set of cut plans which have all of the dimensions measured off of a center line. For an example, let’s look at the plans for the 4ft ship ladder I built.
Click the button below to download a free copy of the plans.
Though the overview on the first page contains all the info needed to make the stringers, it may be difficult to accurately mark out the dimensions if there aren't any flat edges to reference off of.
Now, let’s look at the plans for the stringer modified to reference the center line.
You may be thinking that the drawing using the dimensions based on the center line looks a lot more complicated than the edge-referenced one. One reason for that is because I also converted all of the angular measurements to linear measurements. I find it tedious to accurately measure angles with a framing square. By having everything in linear dimensions we can have a more mechanized process which requires us to think less.
I start by marking the center of each end of the slab. Then, snap a chalk line between the marks to make the center reference line.
mark the 0” point on the center line using a knife edge then highlighting it with a pencil. This point marks the center of the bottom edge of the ladder and I made a line across the bottom so it was easier to see which point it was. I use a tape measure which has 12” before the 0” point for doing these sorts of layouts. This type of tape measure avoids any errors from the end of the tape being loose or imperfections in the material edge.
Mark the length dimension of every feature relative to point O onto the center line.
Now, for each mark of the three steps, make a mark 1-5/16" away on both sides.
Next, from each of these new marks, measure out 3-1/2" and make a mark. I use a framing square with the long, thick arm (the 'blade') aligned along the center line and then measure 3-1/2" along the short, thinner arm (the 'tongue').
Now, use a straight edge to connect the dots and make the cut lines.
To finish marking the slots for the treads, I lay the tongue of the square along the line marked for the bottom of each slot and trace the top and end of the tongue, which is the same thickness as our treads.
Repeat the same procedure of using the square to measure out from the center line to mark the remaining dimensions then connecting the dots.
And that’s it! The hard part’s over. The rest is just cutting the lines.