When I sat down to write this blog, my PC was asleep. I pressed a key and it immediately sprang into life so that I could begin typing. I tend to write my blogs in MS Word before pasting them into LJs and as I type, I receive feedback on my grammar and spelling and change my text accordingly. Hand tools are no different to MS Word really. Lying on a bench or hanging in a tool cabinet, they are nothing more than inanimate objects. Pick them up and use them for their intended purpose and they provide us with constant feedback. We receive and assimilate that information through our senses. We can feel, hear and see when a tool is cutting well and in a split second, respond by making the necessary adjustments. To me, it is a wonderful circle of creativity. We supply power, they respond, we listen and adapt and so it goes on with each revolution of the circle, until at last we move together in harmony towards a shared goal.
I predominantly work wood with hand tools because I really enjoy acquiring and honing the skills they demand. In fact, if truth be told, I probably enjoy the act of refining my skills more than the end products I produce with my tools. It is important that you understand that about me, in order to appreciate why I had to embark on this journey. Now, I’ve often thought that hand tool woodworking really comes down to four core skills. They are sawing, chiseling, planing and drilling. If you master the tools that perform these four tasks, you can do a hell of a lot with wood. However, as we all know, hand tools are useless if they’re not sharp. As Paul Sellers once said:
“Master sharpening and you master your tools. Master your tools and you master wood.”
Whilst I could sharpen chisels, plane irons and augers, saws intimidated me and I had to put that right. What I had not appreciated at the time though, was just how much I was going to learn along the way.I started to list everything I’d learnt on this journey and these are the tangible things I came up with:
- How to clean up a saw plate.
- How to shape and re-finish a saw handle
- How to straighten a wavy saw plate
- How to straighten a bent saw back
- How to select the right file for the number of teeth
- How to change the TPI of a saw by removing the old teeth and filing new teeth
- How to joint, shape, set and sharpen teeth
- How to correct various sharpening problems
- How to reduce the set on a saw
- How to assess the amount of work a saw needs.
- What to look for when buying a secondhand saw that I intend to turn into a user.
- I’ve developed a feel (touch) for how much filing pressure is enough and how to bias the file to correct certain issues with particular teeth.
- I’m getting better at applying a consistent amount of set to each tooth so that I don’t need to dress the teeth afterwards with a stone.
- I’m beginning to understand from a practical standpoint, how the hang angle, length of plate, plate thickness, TPI and the weight of the back work together and how adjusting one of these factors influences the other factors.
- I’m starting to favour certain tooth geometries for rip and crosscut saws.
- I’m developing a better understanding of how to use my saws, i.e. which saw to select, how to stand, how to start each saw, the angle I should approach the cut, etc.
I could go on, but I hope you can begin to see how valuable this journey has been to me in terms of increasing my understanding of saws, what makes them work well and how to use them in different situations.
NOW FOR THE CONTROVERSIAL BIT
I’ve mentioned in previous posts that I would share some controversial opinions that I was beginning to form about saws. Let me say right at the start of this section that what follows is JUST MY OPINION. I can only speak as I find. If you have a different opinion, that’s fine by me. I respect that.
Saw filing is not that difficult and most woodworkers could do it. To me, knowing how to sharpen your own saws and being able to do it is a fundamental skill for any hand tool woodworker. You wouldn’t send your plane irons or your chisels out to be sharpened would you, so why send out your saws? Once you have a saw that is sharpened and set correctly, it should take no more than 10-15 mins to touch up the teeth occasionally. After you’ve sharpened a saw 3-4 times, you will need to re-apply some set (add 5 minutes). You can either do what I did and buy a load of old saws, restore them and use them to learn to sharpen, or you can buy one old saw and just keep practicing on that. Try re-shaping the teeth, changing the rake and fleam angles, joint all the teeth off and try filing new teeth at a different TPI. I can guarantee that after you have jointed, shaped, set and sharpened a saw ten times, you’ll wonder what all the fuss was about.
Fancy shmancy tooth geometries exist because people either don’t know or can’t be bothered to learn how to use a saw properly. Today you hear things like:
“I like to add a touch of fleam to the rip teeth on my dovetails saws”
“I file the first 1” of teeth on my dovetail saw with 8 degrees of negative rake, the next 2” with 4 degrees of negative rake and the rest of the teeth with 0 degrees of rake.”
“The first two inches of my dovetail saws have 20TPI, the next 2” have 18TPI and the rest of the teeth are 16TPI.”
“I file my saws with progressive teeth (small at the toe and gradually getting bigger towards the heel)”
Although some of these filings are historical, in my opinion they are just saw makers ensuring they can still sell their wares to woodworkers who can’t saw. Of course they will all cut beautifully, but anyone can start a dovetail saw with 15TPI and 0 rake along the entire length of the saw if they practice. Hell, it doesn’t even take that much practice to master it. I personally prefer 18TPI on a dovetail saw, but I’m just making the point that if you buy a dovetail saw with one of these fancy filings, you’ll be making more work for yourself when you come to sharpen it. They aren’t necessary and they won’t make your dovetails fit any better.
The quest to find the perfect rake and fleam angles is over-rated. Outside certain parameters, all this talk about adjusting the rake and fleam angles to suit certain woods has been blown out of all proportion. Sometimes you hear people who have had a go at sharpening their own saws say things like “the teeth don’t look very pretty, but the saw cuts beautifully.” Well you know what, they’re absolutely right! Rake, fleam and slope angles are NOT the most important things in saw sharpening. Assuming the back of your saw is straight and you don’t have a wave in the plate, here is what I consider makes a sweet saw in order of importance:
1) Sharp teeth.
2) A straight toothline.
3) Equal amount of set either side of the plate.
I’ve said it before in this blog series and my opinion hasn’t changed as my saw filing has improved. SHARP TEETH WILL CUT WOOD. I’m not saying that adjusting the rake and fleam angles won’t have an effect, but it is nowhere near as important as the teeth being sharp.
Ensuring that the toothline is straight is important on a backsaw. If you can feel some judder or vibration on the return stroke when using a backsaw, then the chances are the toothline isn’t perfectly straight. You will find it easier to keep the toothline straight as you get more confident at saw filing and develop a ‘feel’ for using the file, but to start with, try standing the saw teeth down on a sheet of plate glass or a granite slab and seeing if you can get a cigarette paper under any of the teeth.
Having an equal amount of set either side of the plate is important to ensure that the saw doesn’t drift to one side. When applying set to a tooth, regardless of its size, the tooth should bend from approximately halfway down the tooth, not from the gullet, as that puts undue stress on the metal and you might break a tooth or crack the plate.
Filing slope on backsaw teeth is an unnecessary waste of time. Slope might make a difference on a big 5TPI or less rip saw intended for sawing wet wood, but common sense tells me that the difference would be so small for backsaws that it simply isn’t worth bothering with.
Thinner saw plates aren’t always better. It makes me laugh when saw makers today rave about how their tenon saws have thin plates and therefore cut faster because you are removing less wood. Thinner plates also bend easier and get very hot if you’re cutting tenon cheeks on workbech legs in hard maple. Hot enough that you can’t touch the plate for more than a second. In these situations a thicker plate with a heavier back is better. Thin plates have their place, but they’re NOT always better. It depends on the size and depth of cut and the type of wood you’re cutting.
Not all saw files being made today are equal. As far as I know saw files are currently being manufactured by Grobet, Vallorbe, Bahco and Nicholson. Grobet are the best quality, but hard to get outside the US and Canada. Vallorbe are a close second and are avialable in Europe. Bahco can be good if you get a good one, but they are a bit hit and miss. I’ve had more than one Bahco file where the teeth have crumbled away as soon as I started filing. Nicholson are no longer worth buying. Until they get their act together, they are best avoided.
Having said all that, I don’t want to discourage anyone from experimenting with tooth geometry themselves and forming their own opinions. After all, that’s what I did. Just don’t let it intimidate you and put you off having a go at sharpening your own saws.
Here are my favourite rake, fleam and slope angles for rip and crosscut backsaws.
0-5 degrees of negative rake, 0 degrees of fleam, 0 degrees of slope.
15 degrees of negative rake, 25 degrees of fleam, 0 degrees of slope.
I’ve decided that combination filings aren’t for me. If I had to carry my tools around with me from job site to job site, then a saw filed for both rip and crosscutting might interest me, but I don’t. Since I don’t consider it a problem to put one saw down and pick another one up, I would rather work with two saws; one optimised for ripping and one optimised for crosscutting.
In conclusion, if you’re lucky enough to own a high-end saw like a Wenzloff, Gramercy, Bad Axe, Adria, Blackburn, LN, etc., then you’ll already know what a pleasure it is to use a nice sharp saw. Eventually though, they all require sharpening and it is then that you have to take the decision to either send them out to be sharpened and swallow the cost and the waiting time, or learn to do it yourself and put the saw back on the rack ready for tomorrow.
I find it encouraging that more and more woodworkers today are trying their hand at saw sharpening. I believe it would be a travesty if we let this important skill die and I hope you will all at least give it a go. Don’t expect too much from the first few saws you sharpen, but if you stick with it, I promise you that you will ‘get it’ and you’ll be glad you did.
I’ll leave you with some photos of the saws that taught me about backsaws. When I bought them, they all had their own issues caused by years of neglect, improper storage and/or use, but today they all cut beautifully (except for the leftmost saw in the last photo which is a 10” dovetail saw made by C. Garlick & Sons. I only got that one a couple of days ago and haven’t touched it yet).
So has restoring and learning to sharpen all these saws been worth it? Hell yeah! I wouldn’t have missed it for anything and I’d recommend it to anyone. I will be using and building on these skills for as long as I’m able to work wood. Saws no longer intimidate me.
The next post in this series will be a video post, covering the theory of saw sharpening and will take you step by step through the process. I hope you’ll all stay tuned for that.
-- Andy -- Old Chinese proverb say: "If you think something can't be done, don't interrrupt man who is doing it."