Thread: Saw Sharpening - The Village Carpenter

Hi Jeremy depends what sort of saw he's talking about, he is saying pitch, maybe its a rip and they are working from a gentle angle on the toe (easier to start and get going and then a more agresive rake angle on the heel wich sounds ok to me. I don't think they would be putting a courser pitch (less tpi) on the front and a smaller pitch on the back it would be hard to start and back to front. My LN dovetail saw is a variable pitch which goes from 13 at the fromt to 9 at the heel (works great).
If its a cross cut they might be cahnging the fleam which I guess would also work. I have seen a lot of different sharpening style like cross cut at the toe end and rip toward the heel end which worked very well also. Buy a few old dogs and have some fun

Hi Claw (not Craw! ...Craw) (sorry, I still remember that from Get Smart)

I suspect that the saws were filed rip, but as we know from looking at old saws, even rip saws often had a little bit of fleam introduced by the owner over time and the main difference between a saw used for cross-cutting and one used for ripping was, most often, the tpi and not fleam.

What bugs me about the quoted passage is not only that Rose calls the change one of "pitch" (which suggests a 'progressive pitch' like on the saws Rob Cosman sells for dovetailing) but also the 60 deg and 30 deg angles. Is he talking about tooth shape or rake or what?

As you know, I am a mad experimenter and I am certainly happy to tinker about with some of my less valuable saws, but if I am going to try to see if I agree with Rose's advice, I'd like to work out what he means first

Yes he needed to be a little more acurate with his description for the likes of us that want to try these things. I like a nice agresive tooth shape "positive rake angle" I think he was talking rake rather than pitch (either rip or cross), as I said, if it was pitch it would be the wrong way round, dosey doe, heel to toe

I believe he is talking about relaxed rake. To change the pitch you would have to re-tooth the saw.

Yep, I think you're right, even though I like an agresive rake I often back it of on the heel as well as the toe for the change of direction.

Coming in late here, Jeremy, but my reading of the passage is that he's talking about rake, for sure, since he mentions 60 deg at the front (a 'relaxed' rake to use Claw's term) to the more typical 30 or less at the back. With those sorts of rakes, it would have to be a crosscut, and even then, that's a very relaxed profile. Rips generally run 5-8 degrees of rake, while crosscuts are more like 10-15, though Disston produced some backsaws with 45 degrees of rake, I believe. Let's be clear too, that I'm talking about the angle betwen the FRONT of the tooth & the line perpendicular to the long axis, which is the generally-accepted version of rake - he might be using some other format!

I've mucked about with both progressive pitch & varied rake on the toes of both crosscut & rip backsaws that I made. Relaxing the rake on a rip is easy - start with about 20 degrees & bring it up to the stndard rake over about the first 35mm. On a 300mm backsaw, that gives you enough for making a couple of short strokes for easy & accurte starting, & doesn't intrude on the normal stroke area. I've also tried putting a similar length of finer pitch (either all the same or stepping up to the full pitch, tooth by tooth, which is true 'progressive pitch' I suppose). That's a bit harder to do, and most practical when cutting a set of teeth from scratch.

Either finer/progressive pitch, or relaxed rake, seem to work equally well for me, but relaxing the rake is easier to do. I intend to add this feature to my big 5-point rip next time it needs a good workover, as it can be a right bear of a thing to start, in some woods. I would imagine doing this over about 50-60mm from the toe, but since I haven't tried it yet, I really don't know what will work best on that one, as yet.

Cheers,