Saw Sharpening Question

[Stew Hagerty]

I am relatively new to saw sharpening, but the saws I have done so far seem to cut very well.

When I sharpen a Rip Saw I use 4^o Rake & 0^o Fleam. And, when I sharpen a Crosscut Saw my go to specs are 14^o Rake and 20^o Fleam.

OK, here is my question:

What is a "Hybrid Cut" and what settings are recommended for it?

I have three 12" saws. I've filed one Rip and one Crosscut. I have heard about this other cut and thought I might use it on the third.

[Chris Griggs]

A hybrid saw is simply a saw that works well (or at least reasonably well) both ripping and cross-cutting. You can think of it as an aggressively filed crosscut saw (more aggressive rake, and less fleam) or you can think of it as a rip saw with some fleam. The current saws out there being marketed as Hybrids are the Gramercy Sash and the Bad Axe saws. The Gramercy saw is filed closer to a typical rip, with 5 degree of rake and, if I recall, 8 degrees of fleam. I believe Mark Harrel/Bad Axe files his hybrid with more like 10 degrees of rake and 17 degrees of fleam so they are closer to a typical cross cut. I've experimented with hybrid filing a little bit and found that I like the filing closer to the Gramercy saw for a "hybrid saw". I once filed a 10" dovetail/carcass saw with 10 degrees of rake and 10 degrees of fleam and liked that filing quite a bit for both types of cuts. Another time I filed a 16" diston with 5 degrees of rake and 8 degrees of fleam (same as the Gramercy) - it worked well too but I found that if I was going to use it as a crosscut often I would probably want just a touch more fleam, a slightly more relaxed rake or both. Keep in mind that the disston has a thick probably .032"-.035" plate and the Gramcery has a .020 plate so even though the filing was similar its not apples to apples. I'm guessing the thinner blade allows one to get away with the more aggressive filing and still get nice cross cutting.

I'm actually in the middle of building a 14" sash saw (similar in dimension to the Gramercy) that I plan to file as a hybrid. It will get 5 degrees of rake and 10 degrees of fleam (a touch more fleam than the 16" disston I previously filed hybrid) - it will probably get more use as a xcut than a rip, but in dry hard woods using a smallish toothed saw (12ppi in this case) you can xcut very easily with a minimal amount of rake and fleam. If I decide I want it more towards the xcut end of the spectrum I can always relax the rake to something more like 10 degree and it will xcut easier and still likely rip well enough, for all but the largest tenons.

Some folks will argue that any saw that has fleam (or slope) is by definition a xcut, others out there even file their dedicated rip saws with some fleam. My contention is that a saw is whatever it does well and whatever you use it for, so a hybrid saw is any saw that you use for both types of cut.

So my recommendation if you want to experiment with hybrid filing. Start with a saw filed rip, with maybe saw 5 degrees of rake. Try both types of cuts. Then go back and add 5 degrees of fleam. Cut again, see what you think - how much does the ripping slow down? How clean is the xcut? From there keep adjusting the fleam and rake until you are at a point where you like how it does both in the woods you typically work with. I'm guessing somewhere close to 10 degrees of both rake and fleam is where you'll find a nice compromise.

[Jim Koepke]

Chris answered your question very well.

There isn't any mention of tooth count. The points per inch are also part of what determines a saw's aggressiveness.

A saw with 10 ppi, 8º rake and 5º fleam will seem more aggressive than the same rake and fleam filing at 14 ppi.

My last saw was filed with 13 ppi, 5º fleam and 5º rake. I use it a lot for cross cutting and rip cuts. It has a fairly thick plate at about 0.032". It cuts well and fast.

Here is the post on making a handle for this saw:

http://www.sawmillcreek.org/showthre...Back-Saw-Build

jtk

[Jessica Pierce-LaRose]

Totally off the wall, on a similar subject - anyone ever tried sharpening a western saw with something like a bandsaw blade pattern, or the "Ikeda tooth" pattern, with the unset rakers every few teeth? I figure there's a reason I haven't seen this on a non-logging western saw before, but was curious. I may totally misunderstand how this tooth pattern works.

[Stew Hagerty]

So my recommendation if you want to experiment with hybrid filing. Start with a saw filed rip, with maybe saw 5 degrees of rake. Try both types of cuts. Then go back and add 5 degrees of fleam. Cut again, see what you think - how much does the ripping slow down? How clean is the xcut? From there keep adjusting the fleam and rake until you are at a point where you like how it does both in the woods you typically work with. I'm guessing somewhere close to 10 degrees of both rake and fleam is where you'll find a nice compromise.

I am curious as to what you all think of the angles I'm currently using for Rip & Crosscut?

Rip Saw: 4^o Rake & 0^o Fleam, Crosscut Saw: 14^o Rake and 20^o Fleam.

[Chris Griggs]

Well I'm a competent filer but not an expert by any stretch, but I think they are good standard filings. Seems likely that they are typical and recommended as a starting point for a reason. They work, and if it works, well then work it. Thats about where I file my rips cross cuts.

[Mike Allen1010]

I am curious as to what you all think of the angles I'm currently using for Rip & Crosscut?

Rip Saw: 4^o Rake & 0^o Fleam, Crosscut Saw: 14^o Rake and 20^o Fleam.

Stu, your Rake and fleam angles are right in the middle of the sweet spot, particularly for back saws. Fine-tuning elements of saw configuration (Rake, Fleam and Gullett angles and set) is kind of the difference to me between "sharping" and "tuning" A saw for a specific task/type of wood.

All of these angles exist on a continuum of compromise; the higher your Rake angle (say you go from 4° to 8°), the easier this will be to start and the smoother it will work in the kerf, but the slower it will cut. The reverse is true for a lower rake angle: this isn't that big a difference with a small tooth backsaw, but makes a big difference w/ 5 PPI , 28" rip saw.

Likewise with fleam w/ X-cuts : higher the fleam angle- The faster it will cut, but the less durable the edge will be. Higher rake and gullett Angle sare a little bit more difficult to execute as well.

Four crosscuts with 10 PPI or higher – premium is on precision and accuracy so I typically go with 15° of rake and 25° of fleam angle. For coarser pitch 9 PPI or lower I go at 12° of rake.

All rip saws I use 5 degrees of fleam- not a big deal but helps tracking in wandering grain. Rake I like 8 degrees for finer pitch and 5 for coarser pitch. More experienced washers typically prefer a more aggressive set up (because they don't have trouble starting the saw on line and are less likely to catch a tooth), while new washers maybe better with a less aggressive set up. Experiment and you will find what you like.


All the best, Mike

[Stew Hagerty]

Stu, your Rake and fleam angles are right in the middle of the sweet spot, particularly for back saws. Fine-tuning elements of saw configuration (Rake, Fleam and Gullett angles and set) is kind of the difference to me between "sharping" and "tuning" A saw for a specific task/type of wood.

All of these angles exist on a continuum of compromise; the higher your Rake angle (say you go from 4° to 8°), the easier this will be to start and the smoother it will work in the kerf, but the slower it will cut. The reverse is true for a lower rake angle: this isn't that big a difference with a small tooth backsaw, but makes a big difference w/ 5 PPI , 28" rip saw.

Likewise with fleam w/ X-cuts : higher the fleam angle- The faster it will cut, but the less durable the edge will be. Higher rake and gullett Angle sare a little bit more difficult to execute as well.

Four crosscuts with 10 PPI or higher – premium is on precision and accuracy so I typically go with 15° of rake and 25° of fleam angle. For coarser pitch 9 PPI or lower I go at 12° of rake.

All rip saws I use 5 degrees of fleam- not a big deal but helps tracking in wandering grain. Rake I like 8 degrees for finer pitch and 5 for coarser pitch. More experienced washers typically prefer a more aggressive set up (because they don't have trouble starting the saw on line and are less likely to catch a tooth), while new washers maybe better with a less aggressive set up. Experiment and you will find what you like.


All the best, Mike

This was very helpful, Thanks you Mike. Chris & Jim, thank you as well.

It's really great to be able to have a place where people can share information like this. Without it, I'm afraid that many of these skills would gradually be lost as have so many things over the course of human history. Unless, of course, someone out there still knows how to build a Pyramid, or maybe how to lug 30 ton Sarsen Stones 30 miles to the Salisbury Plain without the use of a wheel, or how about what was actually on all of the scrolls housed in the Great Library at Alexandria....

I hear crickets chirping...