slip stoning a saw

[jim goddard]

Has anyone experimented with stoning a saw after sharpening w/ a file? How did that turn out? Was it worth the time/effort?

[Chris Griggs]

I do it every time. Lightly if I'm happy with the set, and little heavier if the set is a little too much or a little uneven. Removes the burrs and will even out the set a little (won't fix totally out of whack set).

If you want to remove the filing burrs and not impact the set at all, you can take a piece of 400 or 600 grit sandpaper, fold it in half over the line so that it is just hitting the sides (and not the cutting edge, obviously), and just run it down the toothline...does a nice job removing any burrs.

Neither is a necessity, the burrs with come off in use, but it doesn't really take any time or effort. Give it go, it makes the cutting a little smoother when the saw is freshly filed.

[David Weaver]

Same here, fairly fine tooth file and very light touch. Either a file or a medium grit stone (also very lightly). The stone works in some cases where a file doesn't (e.g., for an induction hardened saw).

[jim goddard]

I wasnt concerned about burrs. As you said they disappear in use. My thought is to refine the cutting edge thereby giving it a longer working life which makes for less sharpening and better cut quality. When you stone do you sharpen as often vs a saw thats simply filed?

[Christian Castillo]

I've never refined the cutting edges of a saw with a stone, I don't know anyone who has either.

[Chris Griggs]

I've never noticed any different in sharpness or edge life, but as a weekend warrior I probably don't use my saws to notice a difference even if there is one. I just do it to smooth out the cut via removing burrs and smoothing out the set...or like Christian said, if the saw is pulling to one side I use it to remove a little set on the side that is causing the drift.

[David Weaver]

I wasnt concerned about burrs. As you said they disappear in use. My thought is to refine the cutting edge thereby giving it a longer working life which makes for less sharpening and better cut quality. When you stone do you sharpen as often vs a saw thats simply filed?

Ditto to what the other guys said, working the sides of the teeth is a burr removal and set mitigation/evening process and not something done to improve tooth life.

I have, however, seen old rip saws that had the teeth filed secondarily either as a quickie refresh or to provide more support to the back of the tooth. I have seen paul sellers say that he does the same thing to make the sharpening job last. It is around 26:00 in this video. The nicest carpenter saw I have, an old groves saw that was not marked for export, had the teeth filed expertly and they were finished off this way. Obviously, this is not a job to do on crosscut teeth, but it is somewhat interesting to note that if you did manage to do it on crosscut teeth and then clean up the job and bring the teeth to a point again, it would be the same type of thing that is done to strengthen tall japanese saw crosscut teeth.


http://www.youtube.com/watch?v=UA5DixEaaUo

[jim goddard]

Right, my goal here is to refine the cutting edge. Its the same thing as not using a chisel or plane iron right from the grinder.

[David Weaver]

Oh, the wear on a saw occurs at too high of a rate to do anything to refine the edge the same way we would with harder plane or chisel steel. The burrs themselves aren't really a problem, but a tooth that's set outside the toothline can cause the back side of a cut to be nasty and broken out. if you mitigated the set with another method (by clamping the teeth in a vise or hammering the set out like paul shows in the video above) you can forgo the stoning. Or you can ignore uneven set for practical purposes and not do any of it.

It is good to do a good even job on a saw and get it straight cutting and cutting fast, but I think a lot of the "perfect the job" notion that exists is because the guys who file the saws professionally need to do that neat of a job to stand out and get paid. It's sort of like if I were making planes and I sold you a new plane with pitting in the cheek. It would never make a difference in use, but you wouldn't tolerate it if you were paying full price, you expect an attractive job. You can see from paul's saw that the toothline isn't even perfectly jointed and from experience as you go along you can decide (all goes back to trusting your hands, eyes and minds) how important total neatness is when you do a job sharpening your saws vs. time efficiency and adequacy of the job itself.

You'll find a lot of the saws that professionals use are not filed as perfectly as Daryl Weir would do it, but it doesn't cost the user time or quality of work in the end. Daryl does file the best teeth that I have seen, though, the quality of the job is stunning.

At any rate, have a look at the points on the next crosscut saw you file after you've done a project. You'll notice that they begin to wear on the tips and surfaces that touch the wood very quickly, and that the speed of the cut isn't necessarily affected adversely for quite some time after that. The geometry of the tooth is much more important than the perfection in finish. I've gotten some vintage saws that were filed crosscut, and still sharp enough to use, but I couldn't use them well because they had been filed with so much fleam that they displayed what disston calls rasping in the cut. I never really saw that descirbed until Wiley Horne pointed out at one point that disston had described that in their manual.

Rose antique tool provides that manual as a PDF, it is free (I have no affiliation with any of it, of course).

http://www.roseantiquetools.com/id57.html

(the crosscut discussion is on page 21 of disston's 1939 catalog and is something I haven't seen discussed much).

[Chris Fournier]

I would only slip stone a saw that I had just sharpened if I felt that I had put too much set in the job and even then it would be a mild chore at best. I rarely do this. Look at the teeth under magnification once you have done this and you will see that the nice crisp teeth points are now less pointy - looks like one step back if you know what I mean. Saw works just fine...

[jim goddard]

Just for the record I was suggesting stoning across the cutting edge vs along it.

[David Weaver]

Just for the record I was suggesting stoning across the cutting edge vs along it.

Ahh, then it does seem to have practical merit for rip saws, but not so much for finish quality, but more due to favorable geometry changes.

[Chris Griggs]

Just for the record I was suggesting stoning across the cutting edge vs along it.

Ah, gotcha. I didn't catch that. In that case, no I haven't tried it, and have no useful input.

[Mel Fulks]

I don't sharpen saws,but I've seen a piece soft aluminum used to remove burrs after filing.

[Sean D Evans]

I've thought about it Jim, but haven't actually tried it. I hadn't thought about a slip stone but was thinking more along the lines of this: http://m.spyderco.com/catalog/details.php?product=92
I doubt it would be quite the right size.
This was mostly just something I thought about while sharpening a saw last week. I'll probably never take it farther than that.

[Chris Fournier]

There would be no gains to be made by doing as you propose. A saw cut is always refined by another operation before the piece is integrated into a project. A slip stone would wear quickly and not fit well into the tooth profile messing up your saw.

[Stanley Covington]

If you use Japanese dozuki saws of the kaeba (replaceable blade) variety, using a noviculite stone to remove a bit of the excess "set" is an excellent way to improve their performance significantly. If you think your kaeba dozuki is good now, try this and you will notice it cuts more precisely in shallow cuts.

Just rest a hard noviculite stone with some oil on it on the teeth and dag it from the toe to the handle without applying any downward pressure. Do this on both sides.

Then be certain to use some solvent (mineral spirits or WD-40 is good) and a toothbrush to thoroughly clean and flush the stone grit from the teeth. If the grit is not removed, it will dull the teeth with the first cut, I promise you.

This method works on any saw that has too much set.

Stan

[Stanley Covington]

I was recently taught how to deburr sawteeth after filing by a Japanese sawmaker. It works like a dream.

The tool shown is an extra the sawsmith had laying around which he kindly gave to me. The one he uses daily is shaped nicer, but he said the shape doesn't need to be pretty to work well. As you can tell, he made it from an old file. Interestingly, he said he hardened it using, of all things, a coating of miso paste! Miso has been used by filemakers and toolmakers in Japan for a very long time and is still used today.

The edges are sharpened, and its curved shape lets it ride the teeth as it is stroked along the length of the sawblade and teeth at an angle. It really does remove the burrs very cleanly and quickly creating a sharp tooth.

The picture shows Takijiro (5th Generation Nakaya Takijiro), the sawsmith who gave me the tool and taught me this technique, holding a reproduction of an ancient Japanese saw he made for historical research purposes. A very strange saw indeed.

BTW, the sawblade leaning against the wall on his right is a reproduction of an ancient frame saw blade Takijiro also made for historical research purposes. The blade has iron hoops riveted to each end to secure it to the frame. Notice how the teeth change direction at the center of the blade. Very strange. Takijiro said it is a bitch to get started, and is very difficult to make a straight cut with in a log.

You can also see a Western saw at his left. An archaeology professor that collects saws asked him to have me take a look at it and tell him what it is. Its a Disston No.12. It was once badly rusted and cleaned with some sort of abrasive that removed the etch. But the plate is still straight, and if sharpened, it should still be a good saw. You find the strangest things in the shop of a sawsmith that has been in business for 5 generations and 160 years.

Stan