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."


9 comments:

  1. Great post! That was fun. As for me, I've never used a drawknife but after reading this I'll keep my eyes out for one at the flea market I'm going to on Friday!

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  2. Dan, great post and something I certainly wouldn't have thought of as I have only used a draw knife for cylindrical items. I don't have a bow saw, been looking at them on-line, but haven't made the choice. Though you and I discussed getting rid of the table saw, I think the band saw would stay, that would be hard to let go. However, if I were just starting out, what you propose would be a viable option. Hope all is well up north

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  3. Eric - I highly recommend drawknives - fast, powerful, subtle, and versatile. Just remember, it's next to impossible to cut yourself if both hands stay on the handles. It's when one hand leaves and then comes wandering back that the trouble begins!

    Rick - All is well up here - I've dodged the H1N1 virus so far, but a lot of my students have been out sick (well, some have been out hunting). Snow is very low on the mountains, and getting thick on top. Regarding the bowsaw, there are nice one's for sale, but you can also make your own no problem. I cut up the blades from my bandsaw to make mine :) Of course, you could just buy some extra blades to cut up...

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  4. Dan,
    Another great post! As a hand tool user the draw knife is a tool I still haven't gotten 'into' but
    I think it's now on my short list!
    Having a back ground in wooden boat building spokeshaves were always a tool I'd get a ton of use from...the mechanical process and the physical action is something I really enjoy...almost relaxing in use. So yeah, a draw knife is one I need to get into.
    As for bow saws, I have the one by Gramercy Tools and it's a really well made saw. (for anyone that was curious about purchasing one)
    There's a big vintage tool sale this week here in Ontario, Tools of the Trade Show...I'm going to be looking for a drawknife!
    Keep well.
    Tom

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  5. Tom - Yeah, if you like spokeshaves I think you will love the drawknife - not as refined, but a whole lot of fun! I'm pretty jealous about that Tools of the Trade Show - I'd love to go to something like that sometime. Thanks for the comment.

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  6. I learned another technique for cutting curves at the Center for Essential Education's Woodworking School near Waco Tx. To cut the curves in aprons for a small table, we simply made a series of perpendicular saw cuts down to about 1/8" away from the line, then used a chisel, bevel down, and a mallet to chop out the waste. To avoid tearing out wood below the curve, you have to work one side from the top down to the deepest part of the curve, then start at the other side and do the same. The last step is to clean the curve with a spokeshave. The technique is surprisingly quick.

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  7. Todd - Thanks for sharing that technique - it sounds like a good option. I think it's interesting how many different paths there are to the same destination.

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  8. Just stumbled across your site trying to find a draw knife comparison. know they are something I need to get into. Love using hand powered tools. Have Hirsh chisels, several Veritas planes. Not much money, but don't mind saving for something worth while. Any suggestions where to look for info? How about brands that you (or others) think are really good. THANKS
    MONKEY WITH AXE

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  9. Monkey - Yeah, drawknives are great, as long as you remember to respect that blade!

    As far as finding them - I think about half of mine came from eBay and the rest from antique stores. The only new ones I've seen are either junk or crazy expensive. As long as the handles are tight, and there is life left in the blade, you can't really go wrong. Each drawknife has its own feel created by blade length and curvature, handle angle and shape etc., and I definitely have my own preferences, but really, you can do good work with just about any of them. Good luck!

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