Chris Schwarz's Blog

Rethinking Carcase Saws

We’ve been testing six carcase saws for the Autumn 2009 issue of Woodworking Magazine. And while I can’t share the results of the test with you just yet, I want to share some of the interesting stuff we dug up that didn’t fit in the printed edition.
 
My goal was to answer the simple question: Should carcase saws be filed for ripping or crosscutting? I’m not sure I even accomplished that. So let’s take a look.

The carcase saw from Joseph Smith’s “Key.”

The term “carcase saw” is one that appears fairly early in the literature of English woodworking. Though Joseph Moxon doesn’t mention it in 1678, tool inventories in the late 18th and early 19th centuries mention it by name. And the earliest illustrated woodworking catalog I have , “Explanation or Key to the Various Manufactories of Sheffield” , says carcase saws are 12″-long open-handed saws that are available with iron, steel or brass backs.
 
But not much is ever said about the teeth of the tool. And that’s frustrating because the teeth tell the story of what the saw was used for.
 
Benjamin Seaton’s carcase saw (a well-preserved early 1800s example) is a 14-point saw and has a handle that is angled like his dovetail saw. But we don’t know how much rake was on the teeth when the saw was made or if there was any fleam.
 
(Rake is how much the teeth lean back from the perpendicular, which controls how aggressive the saw is. Fleam is the bevel on the front of each tooth. It controls how smoothly the saw cuts, plus how fast it is.)
 
The question of fleam on a carcase saw is a significant one. Add enough fleam and the saw is optimized for crosscutting only. Some (but not all) scholars contend that there is no evidence that early woodworkers used significant amounts of fleam on their saws , which is why all the saws at Williamsburg are filed with a ripping tooth.
 
So how did early woodworkers crosscut, according to the scholars? With rip saws. You can crosscut or rip with a rip saw. You just have to take care or extra steps to ensure the cut is clean.

Teeth with fleam (at top) and without (below).

By the middle of the 19th century, fleam was everywhere. All the major writers of the time comment on it and it is available on many saws. Charles Holtzapffel’s seminal work on the craft has a fantastic chart of all the saws available for woodworking (download it here). He lists the carcase saw as being 10″ to 14″ long, having 12 ppi and a form of tooth that could be crosscut or rip.
 
Modern carcase saws are typically filed crosscut, though rip versions are available from some makers.
 
But none of this answers the question: What are they used for?
 
The name “carcase” implies that they are used for cuts in casework, but that can be anything. I have always used a crosscut-filed carcase saw for trimming rails, stiles and boards 6″ wide or narrower to length. Plus all manner of notching, cutting pins and muntins to length, and removing waste to install locksets. I usually use my carcase saw with a bench hook (as shown in the magazine pages atop this entry).
 
But what if the carcase saw is supposed to be filed rip?
 
Adam Cherubini, the writer of Popular Woodworking‘s Arts & Mysteries column, and I got into an e-mail chat about this topic.
 
“I always thought of carcase saws as the dovetail saw used to saw out the larger dovetails on carcases,” he writes. “London drawer components got thinner and thinner as the 18th century wore on. At its dawn, drawer sides were often quite thick as side-hung drawer runners were used.  When that design was put aside, early in the century, drawers got substantially thinner.
 
“London drawer sides got down to about 3/8″ thick with big drawers and were as small as 3/16″ for little drawers. Most folks point to a lumber shortage in London as the cause, but I find thinner stock significantly easier to deal with.
 
“It could be that ease of use and reduced cost of sawing associated with mechanized lumber mills or just improved saws (steel!) and business practices made thin stock preferable. The drawer stock thickness of course affected the sort of saw required. Thin stock really requires fine teeth while the 7/8″ carcase sides were better done with another.
 
“I don’t think the name (carcase saw) means much to modern woodworkers. But it should.  For if a carcase saw is designed for cutting carcase dovetails, it should be optimized for its purpose with nicely raked rip teeth and a long narrow (and thin) blade. I think some sawmakers are hanging too much steel under their spines for these saws.”
 
To me, this implies we should continue to call the smallest backsaw a dovetail saw and rename the carcase saw as the condortail saw.
 
It sounds like I need to start using a rip carcase saw , sorry, condortail saw ,  for carcase dovetails and see how it works.
 
- Christopher Schwarz

15 thoughts on “Rethinking Carcase Saws

  1. Sean

    I always look forward to what Chris learns about most anything. You too.

    I don’t mean to say I know better by any means, but only to report my first hand personal experiences for what little they may be worth.

    As far as being a great craftsman, that is certainly not the case. I’m just a hobbiest with high hopes.

    If you want a giggle, take a look at this goofy 1:30 video I made when I got my Flip mino HD (a great toy by the way) – it’s mostly playing with the sound effects pre-loaded on my Macbook, but you’ll get to see me saw, and that should quickly dispell any thoughts about great skill or crafstmanship on my part!

    http://www.flickr.com/photos/chevy_chase_hughtos/3496155520/

  2. Adam Cherubini

    Tiny bit of carving is left. I’ll start the finish this weekend.

    I see two schools of thought related to this subject. One side says find a tool that works and stick with it. You may be sympathetic to that approach. But that’s not Chris’ job.

    My concern is always that the devil is in the details. So I can talk about all the great work I do. You Sean, certainly do beautiful work. But how we got there is often more complicated than either of us may perceive. It’s important to find out what is it about this tool that makes it well suited to it’s job? A great craftsman, you may be one, can saw dts with a Crown Gent’s saw, new out of the box. But that doesn’t help the guy who doesn’t have tons of experience. Or the guy who wants to do more than you have done. Or wants to work faster than you’ve worked.

    I’m looking forward to what Chris learns.

  3. Sean

    Adam, your points make sense. I will say that in my experience cutting dovetails in large carcases or chests, the sawing is the least of it and goes very fast. I have used LN and Gramercy DT saws, along with a rip dozuki in these applications and found all did the job well and quickly. A 12" carcase saw with a few less teeth per inch or less rake wouldn’t have bought me much time savings unless it could have chopped out waste and pared to the base lines. Here’s a pic of a test fit of one set:

    http://farm4.static.flickr.com/3095/2864599314_94da5d121b_o.jpg

    Glad to hear from you. Is your chair done?

  4. Adam Cherubini

    What I think is at stake here is that 2 dovetail saws are required for period work. One saw, let’s call it a dovetail saw) might be optimized for sub 1/2" stock. It should be short, have a shallow depth of cut and should have very fine teeth so as not to bend and split thin stock and to allow for a controlled depth. The other, hmm, let’s call is a carcase saw, could be set up for the only other place we see lots of dovetailing in a period shop; carcase dovetails on cases. Since carcass are almost always 4/4 stock, this saw should be longer with coarser teeth,

    Yes, you could use the finer toothed saw for both operations. Heck, I can cut dt’s with a hack saw. The issue is, guys in period shop optimized their tools for their work. I can spend a day or more making nothing but drawers. I could be using my dovetail saw for hours and hours in a single day. When making a carcass, I’m cutting 100-200 dts. That can take me 4-6 hours (not all of the time sawing). Having saws optimized for these uses makes sense to me.

    My opinion is that saw makers, worried folks are too cheap to buy 2 dovetail saws are detuning their saws to function for thin and thick stock. They have coarse teeth, but then add gobs of rake to make the cut less effective, more palatable in thinner woods.

    Remeber that aha! moment when you first used a good plane or a decent saw? You’ll get that again when you use a saw that’s been set-up specifically for the job at hand. And you’ll be glad you have it when you are staring down a 22" piece of walnut you want to make a chest of drawers out of.

    Adam

  5. Mike

    Hey Dean–right on!

    A small panel saw is great for larger tenons. As a bit of poking fun at people thinking fine-toothed saws are needed for joinery in 3/4" boards, I lastly used a 26" 5 ppi rip for some larger dovetails at an event. Certainly they were not single-entry DTs, but starting the saw and sawing to the lines wasn’t an issue.

    But I agree, Dean. A largish tenon saw makes for a more controlled experience in sawing tenons. My favorite vintage saw is a 21 1/2" 8 ppi tenon saw. Mostly for the size of tenons I use to make (time is a killer these days), I use alternately a 14" sash saw or a larger tenon saw.

    Take care, Mike

  6. Ray Schwanenberger

    As a person who enjoys collecting and using well made tools I see this as an opportunity to acquire not one but two fine tools. There is nothing like trying to do a job with the wrong tool. So in the spirit of my Boy Scout days, I like to "Be Prepared".

    Chris allow me to say that I quite enjoy your thinking outloud. As a result of your thinking, through this blog, I have found myself looking at the way I do my work, the tools I use for a particular task, and exploring different methods with different tools. Sometimes the results are very pleasing, others raise more questions (what the heck is "The Schwarz" talking about). No matter, I believe this is how we learn and expand our skills, discover what works for us and what does not. I look forward to your next cerebral voicing and the Autumn 2009 issue of Woodworking Magazine.

  7. Mike Cundall

    I think the research aspect that Chris is onto, and of which I am a friend as an academic, is to answer basic questions as to the function of the saw. But then related questions as to why person X thought the way that they did can pop up and be enlightening. If there is a reason Person x believes carcase saws made in a perticular fashion worked well for thus and such job, why did she believe it? Person X may be wrong, or they may have found something we haven’t seen or appreciated as yet.

    Sometimes figuring out why a person believes in the way that they do makes a larger problem more tractable or at least gives us an entry point into the discussion. But hey I’m a philosophy prof. so esoterica is part of the trade. Good day all and thanks for the postings.

  8. Dean Jansa

    Funny, I just cut some tenon cheeks with a full-size handsaw this weekend — right Mike? :)
    They work, but I still think a full sized tenon saw is a better tool, perhaps because its weight helps speed the cut along and the hang is better suited. But I don’t want to add more fuel to your mind’s fire!

    FWIW, I use my carcase saw for "condortails" as well. I tend to lean on my sash saw for smaller scale tenons, etc.

    Dean

  9. Christopher Schwarz

    Sean,

    I’m not trying to be evasive. Promise. Truth is there is a lot about saws that I just don’t know.

    I’m not having trouble with my saws. I’ve been handsawing since I was 11 so there’s no mystery to the act.

    But I keep finding filings and saw characteristics that are better than the ones I used to use. And I find that you can use different combinations of saws to build furniture.

    I guess I’m trying to understand saws in the same instinctual way I know handplanes.

    On the historical stuff. Peter Nicholson says tenon saws are for crosscutting shoulders — not for cheeks. And George Ellis shows typical tenon cheeks being cut with a full-size handsaw. To me, that makes me think (out loud, apparently).

    Chris

  10. Samson

    No no, do keep on. I like your blog. I’m just confused as to the aim here. In my expereince, you inevitably come up with good practical advice and insights. Perhaps I’m just impatient with all the sort of mystery of "Peter doesn’t think so" and "George nods" and "When Adam stepped out of his time machine …" ;-) What problem are you hoping to solve? I hear you saying your looking for new insights into saws. Do you find that your saws routinely let you down? If so, when doing what exactly?

    My problem is most likely that I’m not enough of a saw afficionado to appreciate the subtle differences – like asking a hack violinist to appreciate the differnces between a Stadavarius and a middle of the road modern production model.

  11. Christopher Schwarz

    Sean,

    You might want to delete me from your RSS feed.

    This carcase saw post is just the beginning of some posts I’m working on that challenge what I know about saws.

    Sure, it all comes down to the simple "whatever works," but what is surprising is that what works is a wide range of saws and filings.

    And it might lead me to use my saws in different ways. Are tenon saws for tenon cheeks? Peter Nicholson doesn’t think so. And George Ellis seems to agree with him.

    And finally, my apologies. This blog is my petrie dish (usually infected with stupid animal idioms) that I use to work out my ideas. That’s probably not how you should use a blog, but oh well.

    Chris

  12. Samson

    Forgive me, as I thought I thought I had a strong stomach when it comes to extreme woodworking esoterica, but I think I’m reaching my limit here. Do you find in your experience that the conventional modern conclusions — that rip performs best with the grain and cross-cut, across the grain — are faulty? If not, are you simply interested in the issue as an historical aside?

    Rip filed carcase saws are most useful for tenon cheeks in my experience. While a smaller carcase saw – around 12" – is fine for dovetails in up to 1" stock, it’s not much slower to use a 9" dovetail saw for the same application. With tenons, the larger saw earns its keep as its size allows it to cut through the width of the cheek more efficiently and to go much deeper as is often required for larger tenons.

    My dos pesos. As always, your milage may vary.

    Best,

    Sean

  13. Bob Demers

    For a deceptively simple looking tool, there is a lot going on ‘in’ a saw! No wonder thee are so many permutations of this ‘simple’ tool.

    Fascinating topic isnt it?

    Bob

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