Thread: Saw File a dud, need advice

There were two GDs in the trial, bothe apparently bigger than what Luke sent you. One was citric acid treated and the other not.

Then, about 304 years ago I sent you a new Japanese file that Schtoo sent me. I think you misplaced that one for *quite some time*.

Then just recently I sent up two more of them to you.

There was possibly another one that I sent you (pretty sure from Schtoo) that had fat flat corners (or maybe I didn't send it because it would have been useless anyway).

Originally Posted by IanW

Stress concentration at a sharp corner in metal is a well-known engineering principal. One of the more famous examples was the breaking-up in mid-air of a couple of the first commercial jetliners, however, whether it is responsible for any significant tooth breakage on hand saws I doubt also.....

Cheers,

I think the main reason for teeth breaking is setting a tooth in the wrong direction (the tooth becomes work hardened ad brittle). Of course with second hand saws we never know how many times this has happened before. Using a saw file it is almost impossible to get a sharp gullet. It is just a question of how round. This all precludes our own personal idiosyncrasies in the filing operation.

Regards
Paul

Originally Posted by IanW

Stress concentration at a sharp corner in metal is a well-known engineering principal.

Yes, in Industrial Arts (at High school, somewhere in the third third of the 20th C) we were always told that a 90° corner was the start of a crack, and you'd have to assume that 60° would be even more so. However, is there any anecdotal evidence of teeth dropping out as a result? The fracture would have to go up into the blade further to be identifiable as such.

Originally Posted by D.W.

100% agree with all of it. I touch up a general rip saw at the beginning of each project, even if it's only 25 board feet of wood. If the saw feels like it needs persuasion to get that filing of fibers feeling when you cut, then I touch up again. The one rumor I'd like to squash is the idea that a saw needs to be jointed and set at each sitting - it leads beginners to think sharpening a saw isn't part of the woodworking process, but rather something that is to be deferred like a day of changing oil and spark plugs on a car. Crosscut saws less frequently (especially the finer saws), but when they lose the ability to cut without undue influence - I guess that's really sort of like using planes. when the plane won't stay in the cut by itself, you can be tempted to push it, but you're just expending effort, not saving it.

Never heard the bit of a weak point occurring at a sharp gullet, but it could be true and it may not be. Saws with brittle teeth tend to break and snap - we all know the little pucker you get with a nice saw when you go to set the tooth, and you don't completely break it, but you hear something funny. The next bit of pressure you put on it, snap. I never keep a saw that loses a tooth during setting. it could be a one-time thing, or maybe not, but it makes the odds higher that it'll happen again, and I'd rather cut wood than file toothlines.

As David would be aware there was a recent discussion on the u.k forum regarding the need to joint the saw teeth prior to sharpening. The strongest proponent against jointing was Jacob Butler. The following post formed part of Jacobs argument against jointing;



Jacob wrote:

No prob - as long as they are sharp and have roughly equal set both ways, it will cut. Teeth can go a long way out before they need topping - and even then it's sometimes not essential to top the whole edge - just the most irregular bits. This dramatically increases lifespan - excess topping is the fastest way to wear out a saw.

Well I don't think that rumour has reached here, so doesn't need squashing. Or quashing for that matter.

I don't think it's made it to most shops where people are using their saws and touching them up frequently. It's just too much of an obligation, and it wastes files on top of that. And causes a mental issue where you'll delay sharpening until you absolutely have to - who would want to work with saws like that? I wouldn't! If I'm dimensioning in a 3 hour shop session, actual time of a saw in motion could be a half hour or so, combined with planing and marking. That's an awful lot of time with a saw going up and down frustrating you if you don't feel like it's letting itself into the wood far enough without undue influence.

I never paid much attention to the jointing thing (certainly do it for a new used saw that's out of whack, but only once), and am not a historical reader, so if there is precedence in any of the old texts (old as before mid 1800s when there would still have been a lot of hand planing and hand sawing), I wouldn't know.

The rumor showed up on SMC years ago, and someone who has worked without any power tools for 40 years finally spoke up and squashed it as being absurd. It gains traction if people are only restoring saws and never using them much, or are only sharpening saws for other people who haven't been properly cared for. Sort of like sharpening routine discussions where someone who only instructs beginners asserts as fact that you can't produce a good edge consistently without a guide and work through a very prescriptive sharpening process (and there's no shortage of that kind of thing).

I'd bet in the old days, the craftsmen (not saw sharpeners, but craftsmen touching up their own saws) also used their saw files until they were *completely* dead. If you're only touching up, a file that's slowing down a little isn't that much of a problem. I'd bet they only corrected teeth significantly if it showed up on the work, too (which will happen if the teeth get bad enough - but it takes quite a bit).

It would be interesting to see an entire thread of difference or no difference for experienced users.

When I first started acquiring saws (which I have stopped, I have what I want now and sold off the rest), I would joint a tooth line flat and then chase some breasting into the saw. There's plenty of advocacy of the breasting really improving the experience of the user.

I have to admit that I can't really tell anything in terms of effort, speed or quality on the back side of a cut, so I've stopped it. When sharpening/touch up, I generally make sure that I file the front and rear teeth a bit harder than the center (only a tiny amount) so that anything that shows up over time will be breasting rather than a frown.

There must be dozens of other things like this that beginners get stuck agonizing over whether or not they need to know about them. Some proponents will describe a specific aspect as making a saw markedly superior, but I wonder.

Slopped gullets is another. With advocates decrying flat sharpened crosscut teeth as almost unusable. I've never seen a speed difference, and file some both ways. I'll never file enough saws to come to a solid conclusion, but a beginner sharpening a crosscut saw may read some things and determine that they'll and up with a substantially inferior saw just because they don't have the kit or experience to file in sloped gullets.

Originally Posted by FenceFurniture

....is there any anecdotal evidence of teeth dropping out as a result? The fracture would have to go up into the blade further to be identifiable as such.

Yes, Bett, but anecdotal is definitely the key word. Over the years I've read a few times where supposedly experienced saw people have talked about it happening. I've seen a few saw teeth myself that would fit with stress failure, cracks running well into the body of the saw. As I said, I've just seen the end result & have no idea of how the saws were used to cause it. I've never had a saw of mine loose a tooth, even though I've had my share of hitting an occasional bit of unexpected hardware..

Cheers,

Wouldn't have been much of a question back in the sixties...

Most things are good in moderation! If a saw is all cows & calves and needs serous remediation, then some judicious levelling makes the job far easier for a semi-skilled saw-sharpener like myself. How would you deal with something like this? tooth wear.jpg

Woops, that was a former life.. But I've seen quite a few saws that looked a bit like that.

Now there are are still a few people around who are practised enough to be able to correct a badly-sharpened saw by eye as they go along, but it's not easy, and I certainly find it's far quicker & more economical to run a file over it to get myself a level playing field. I'll also sometimes take a few light passes over a saw where there's a persistent high tooth or two. It only takes a fraction of a mm difference, which is difficult to spot looking from the side, even when you know roughly where they are. And let's face it, a few light strokes doesn't remove horrendous amounts of metal, even a heavy jointing will only take off a fraction of a mm or so (of course it will be more if the saw is heavily scalloped or an absolute mess like the animal above). Heavy jointing should be necessary only a few times in the total life of a saw, so it's not going to amount to all that much extra wear.

The Jacob Stewie quotes seems to take the contrarian view on any topic. I'd suggest he doesn't saw much hardwood, and certainly not Aussie hardwoods if he reckons a few high teeth don't make much difference! You can get away with a rough job if you only saw softwoods, but it's a bit different with our Aussie hardwoods! Try bringing a saw with a high tooth or two down across the grain of a bit of hard wood as when finishing a tenon-cheek and you know all about it! Rough as guts.

There is nearly always a slightly high tooth or two on a freshly-sharpened saw. These obviously take more of their share of the load & soon wear down, giving you a smoother action, but still adequate cut. If he roughness persists after a few cuts, it's better to find the culprits & deal with them, I reckon.

There is no doubt even a poorly-sharpened saw cuts better than an utterly dull one, but there's also no doubt in my mind that a well-sharpened saw cuts far better, & certainly more smoothly, than either....

Cheers,

Logic says that if you’ve got high teeth, the teeth around them aren’t doing their share of the cutting - you’ve essentially reduced the PPI count, and will consequently have a rougher finish than if the teeth are jointed.

Originally Posted by FenceFurniture

Assumes no 9ppi. (can't say I've ever heard of one)

Brett

9ppi was a regular tooth size. I have several, but each time I was at home it was either too late, too dark, too cold or I was too much "not in the mood" to go looking. These are some advertisements that indicate the range of tooth sizes commonly available. I would suggest that 8, 10, 11 & 12ppi are the most common crosscut configurations with 7 and 9ppi bring up the van so I can quite understand why you may not have seen one. I have a few saws so am more likely to have them come across the bench.

1910 Biddle hardware Disston.jpg1910 Biddle hardware Disston 2.jpgAtkins 1928 Adv.jpg

Simonds 1916 cat.jpg

Something that I have just recalled as I am posting is that the "boys" saws were all only 9ppi. So that included the Disston American Boy (there is another Disston "boys" saw but the name escapes me for the moment), Atkins Junior Mechanic and Simonds Blue Ribbon Junior. This is the Simonds Junior. You can just see the "9" in the enlarged pic.

Simonds Blue Ribbon Junior.JPGSimonds Blue Ribbon Junior 9ppi.jpg





Regards
Paul

Goodo Paul. It would be interesting (but probably impossible) to know how many they actually sold. It's hard to think of a chippie thinking "My 8 is just a little bit coarse for this, and the 10 is just a little bit fine, so I think I need to buy a 9." There is, after all, only 12½% difference between an 8 and a 9.

Perhaps they were for the Fence sitters.... (that, ah, doesn't include me or anyone I know)

OTOH, if someone did have an 8 and a 10, they could always add a 9 with perhaps a little more set, rake, or fleam or whatever. As the only person in the known universe to have 6 of each saw all filed differently, perhaps you could comment?

(I'm serious, he does. fletty and I have seen them in the 20' container Saw Tool Room. There are nil other tools in there besides saws - maybe some files. We were denied entry to the last 20' container..... )

Brett

In fact I would suggest the opposite to you. I think that a person who could only afford a single saw or only needed a saw occasionally may chose a 9ppi as their only saw: This of course would depend hugely on their intended use. You are quite right that I am in an unusual position regarding saws and selection (for the obtuse among you I am nevertheless seated in front of the computer in a more or less conventional position ).

As to numbers of saws sold by ppi, I have no idea other than what is in the collection. However, overall we are talking many millions.

Regards
Paul

Originally Posted by FenceFurniture

Goodo Paul.

.........As the only person in the known universe to have 6 of each saw all filed differently, perhaps you could comment?

(I'm serious, he does. fletty and I have seen them in the 20' container Saw Tool Room. There are nil other tools in there besides saws - maybe some files. We were denied entry to the last 20' container..... )

2A74FA65-A97F-4BCB-B95B-8C186ABCA8C2.jpg 23C6F681-054D-4465-A67D-75B59E3817F5.jpg

So, what’s in the LAST container eh?