I Cant…

 

 

 

 

 

 

 

Ever since I first saw the hand saws pictured in Joseph Smith’s ‘Key to the Various Manufactories of Sheffield’ I have been obsessed with them. A copy of the plate adorns the wall above my desk. The logo for my business is an image of the full size handsaw atop the plate. And I constantly refer to the entire book for inspiration and reference for any old tool.

One of the most striking elements of the saws shown in Smith’s Key is the cant, or tapering along the depth of the saw plate, shown in the backsaws. There is much speculation about this taper, including if it was a purposeful design feature, or the result of sharpening over time. (For more on this discussion, see Ray Gardiner’s writings at backsaw.net) I think the fact that Smith’s Key was a catalog of new tools is evidence enough that the taper was intentional on the part of saw makers. So the real question is what was its function?

Someone asked me this very question last weekend while I was giving a presentation on hand saws at the New England chapter meeting of the Society of American Period Furniture Makers. I have a number of opinions on the matter and they all relate to the function of the saw. It aids in cutting joinery, it makes the saw lighter and improves balance, and it changes the aggressiveness of the cut, just to name a few effects. Plus, it looks damn cool.

But what about the extreme cant shown in Smith’s saws? Especially the carcase saw??? That thing looks as slanted as a ski slope…would it really be helpful? A ‘normal’ amount of cant for a 12 inch backsaw seems to be around 1/8 to 1/4 of an inch along the length of the plate. By my calculations, Smith’s carcase saw shows well over 1/2 of taper….that’s extreme man! Is it exaggerated? Was the engraver drunk? Stoned? Blind? All three? Or perhaps he was the same guy that Moxon hired to make the plates for his book? (Don’t you love historical tool humor?) ;)

Well I’ve been asking myself all of these questions for a while and I finally decided to seek an answer. So, I’m building the carcase saw from Smith’s Key. I was laying out the cut on the saw plate for the cant the other night and had to take a step back…it really is wild. This thing could turn out to be a 12 inch paint scraper!

 

 

 

 

 

Anyway, to me, resurrecting long forgotten tool forms is about as exciting as it gets, and this is a project I’ve wanted to tackle for a while, so I’m super pumped about it. I’ve got a crazy travel and teaching schedule coming up in the next couple of months, so I’ve got to get this little lady on the dance floor soon….

I can’t wait.

;)

-Matt

13 Responses to “I Cant…”

  1. Mitch Wilson says:

    You forgot to mention that your talk was extemporaneous, enlightening, and nearly unending. You are bringing this little lady with you tomorrow to CVWS, right?

  2. Jesse says:

    That plate started a bit of an obsession for me as well. I’ve got a dovetail saw kit that I’ve been trying to decide just how much cant to put on the blade and still balance function with aesthetics. I’m looking forward to see what you have to say about this extreme degree of…cant-edness? cant-tery? cant-eslope?

  3. Jamie Bacon says:

    Looking forward to this. I’ve always loved the Smith’s Key saws. I have a file very similar to yours in the last picture of scans blown up to actual size from the picture.
    I noticed the saw you were shown with at the SAPFM event and the one from your 2/14 blog entry (probably the same saw) has a steel back. Looks folded. Did you do this back yourself? Do you notice much difference between the steel back and the brass back in the way the weight affects the cutting speed of the saw? She’s a looker for sure. Sorry to read you won’t be producing saws but if it’s teaching and sharpening that’s your passion, then that’s what you should pursue.

    • matt says:

      Jamie

      There are certainly differences between steel and brass backs….but to compare one to another is difficult. Its apples and oranges…unless two backs were exactly the same gauge, size, etc, I don’t think a weight comparison would be very telling.

      Matt

  4. Kalon says:

    Matt, I’m also intrigued by Smith’s key
    Can’t (excuse the pun) to see what you come up with… besides how many scrapers can you have?

  5. Pedder says:

    Hi Matt,

    following the plates, the spine has to be tapered, too. We did this on a few saws and the came out great performer!

    Cheers
    Pedder

  6. Brad says:

    Well Matt, paint scraper aside, what you’re doing is referred to as experiential archaeology. You’re testing the historical accuracy of texts by building what’s pictured. And I look forward to hearing what you discover from this process.

  7. Toby says:

    Handsaws and panel saws taper down towards the toe, why not back saws? Lighter on the toe, stiffer (stronger) on the heel.

    Toby

    • Wesley Tanner says:

      I would have to agree. If saws made before backing were canted, then at the first instance of a maker backing a saw, wouldn’t he just put the back on an already existing saw? After that trade habit would just continue in making them thus.

      Wesley

  8. Rob Porcaro says:

    Matt,

    Here is my view of the reasons for cant in a saw. I would appreciate your comments.

    While it is true that the cant lightens the distal end of the saw, its main function is to naturally present a skewed approach of the tooth line into the cut. Note that all Japanese pull saws are canted in the opposite direction and so serve the same main function. Using a non-canted saw, I think most people would naturally maneuver it to produce a skewed entry of the tooth line into the cut to make the sawing feel smoother. The cant assists this.

    This skewed push of the tooth line also can help a bit to reduce fringes on the exit side of the kerf.

    I suspect that the carcase saw in the picture has a lot of cant because that saw is fairly long and is likely to be used at bench level, such as with a bench hook, where there is not much room to induce a skew by dropping the handle.

    For me, a canted saw just feels like the intuitively natural way to saw.

    Thanks for a very informative blog, Matt. I learn from it.

    Rob

    • matt says:

      Rob

      Your reasoning appears sound, but I’ve got a lot of experimenting to do before I know for sure. I don’t think we’ll ever really know why makers canted their saw plates.

      Matt

  9. Rob says:

    Hi Matt,

    Your post inspired me to measure a couple of my old backsaws. For some the tooth line is so up and down the measurements might be meaningless but these two look straight:

    Thos Turner 10 inch dovetail, tapers from 2 3/16 in down to 1 13/16 in;

    Richard Ibbotson 12 inch tenon, barely any taper at all – 2 1/2 down to 2 7/16 in.

    Interesting stuff – thanks. Rob

  10. Dan Murphy says:

    As Rob Porcaro pointed out, it’s natural to tip a noncanted (uncanted?) saw back a bit for a smoother cut. This is probably why the handles on noncanted saws generally have a more relaxed hang. So to some extent, the cutting geometry evens out. But as Matt says, canted saws still have several advantages:

    1. You’re less likely to oversaw your baseline on the far side of the cut.

    2. The cant (and extremely relaxed hang) on dovetail and carcase saws make it easy to saw into the near corner of a board – very helpful when cutting dovetails.

    3. A canted saw is lighter, and its centre of gravity is closer to the heel. This gives a smoother cut with more control.

    These three advantages get mentioned frequently, but I think there might be a couple more (these are just my own thoughts and I’d appreciate some feedback):

    4. It’s good practice to lift your saw slightly on the return stroke: it helps clear sawdust and saves wear on the teeth. With a canted blade, just pulling the saw straight back automatically incorporates a lifting action.

    5. The heel of the blade receives more support than the toe (since the heel is braced by the handle as well as the spine). So a canted blade might help to equalize support over the length of the blade.


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