Wednesday, September 30, 2009
Bowsaw and Drawknife: Two Reasons You Don't Need A Bandsaw
"What about curves; don't you need a bandsaw for those?"
This question, or something similar, is one that often comes up when I discuss woodworking using only hand tools. It's a natural question, but there are at least two reasons why the answer is "Nope, you don't need a bandsaw."
Reason One: the bowsaw.
Reason Two: the drawknife.
This post is a casual exploration and comparison of these two reasons. I was not being scientific, or particularly picky about final finish. Just a quick, fun comparison of two different approaches to the same task.
First, I needed the curves. I chose to lay out an ogee curve as I though it might be more fair to compare making both concave and convex curves.
Then I grabbed the tools:
I decided to start with the drawknife. I clamped the stock in the vise, set a timer and had at it. Here's what it looked like after 4 1/2 minutes:
Next up was the bowsaw. Same procedure - vise, timer, and go. Two and a half minutes later:
At this point, just shaping the curve to the line, the saw was faster by two minutes. But both surfaces needed cleaning up with spokeshaves - both flat and convex sole. During this stage of the process the drawknife had a huge advantage, as the surface it left was much closer to a finished surface. Here's a chart of the total results:
Not too bad - probably not as fast as using a bandsaw, but certainly not slow - at least in my book.
And a shot comparing the final curves:
Not perfect by any means, but again, this was just a quick comparison of two techniques. To me the resulting ogees are the same - or close enough... That's not to say there are no differences in the two methods. For one thing, the drawknife produces a pile of waste chips while the bowsaw produces usable scraps:
Another difference is that if you don't have spokeshaves, careful work with a sharp drawknife can produce an acceptable surface. Also, the drawknife could produce a faceted surface, if that is what you wanted. Of course, using the bowsaw is a lot less scary than holding 10 inches of sharp steel between your hands. I've never hurt myself with a bowsaw, which is something I can't say about a drawknife.
So, to wrap up, both of these hand tool approaches will produce curves without resorting to using a bandsaw. Both take about the same amount of time. And both will allow you to say "Nope, you don't need a bandsaw."