Unset raker teeth for regular woodworking?

[Charles Guest]

Every tooth on a handsaw does not have to have set. The only requirement is that the ones that are set are even (or have less set) with the others on the side to which they've been set. What you can't have are rogue teeth that are overset vis-a-vis the rest of the teeth set to that side.

[William Fretwell]

It comes down to when does a saw blade need raker teeth? Painting the front of the raker teeth should tell you if they are doing anything. If the set teeth have some overlap in the middle then the middle of the cut already gets twice the blade attention.

[steven c newman]

I have no dog in this fight. other than what I saw and heard back then....

Until a blade is made and USED to that videos' standards....everything else is just....hot air...

So, I'll just sit back and wait for the OP's trail run....

Theory is fine, when sitting around the fireplace, and shooting the breeze.....yet...practical usage will always win...over hot air. So, unless one has that particular saw in their hands...just mere speculation ( and a quarter...)

[Luke Dupont]

It comes down to when does a saw blade need raker teeth? Painting the front of the raker teeth should tell you if they are doing anything. If the set teeth have some overlap in the middle then the middle of the cut already gets twice the blade attention.

Could it be that we're conflating specifically designed raker teeth with unset teeth?

A traditional raker tooth is used on a crosscut saw, in green wood, to my knowledge. Now, my post says "raker tooth" but I am just referring to leaving some teeth unset. They have no special difference in shape, rake angle, or height, and are the same height as all other teeth. A greenwood raker tooth on the other hand is a different animal: it's often shorter than the other teeth by a bit and designed not to actually interfere with the cut, only to scoop out sawdust.

I am thinking the unset teeth will still engage in the cut. If the cut cannot proceed without the kerf being fully established, the saw would never move or proceed any further in the first place.

Anyway, making progress on the blades, so I'll do have an answer to this soon enough. If the teeth aren't doing anything, I should expect the blade with 1 out of 3 teeth unset to cut at only 2/3 the speed of the blade with all teeth set.

[Jim Koepke]

I am thinking the unset teeth will still engage in the cut.

This is also my thought. The unset teeth might actually stand slightly taller than the teeth that are set to one side or the other.

As Steven said, the proof is in the finished saw being put to wood.

jtk

[Luke Dupont]

I finished cutting the teeth and drilling the holes in two new blades.

I did as Jim suggested and doubled them up so that I could make two at once, and the teeth would come out exactly the same shape, size, rake, etc. on both blades.

Tomorrow I need to set the teeth and make a shorter stretcher for my bow-saw, then the testing can begin!

These are quite short at 350mm (about 15"), 8TPI. I wanted to experiment with thinner blades as well as the tooth set, so this time I used 0.3mm steel instead of 0.5mm. This is about the thickness of many Japanese saw plates, and is really pushing the limit I think. Might be a little too thin, but we'll see. They seem sufficiently sturdy.

I will take special care when setting the teeth to make sure that they're not over set such that there is a gap on the blade lacking raker teeth.

350mm-bowsaw-blades.jpg
350mm-bowsaw-blades-2.jpg

By the way, to drill the hole, I finally gave up on my worthless twist bits (even diamond bits) and took a hard, round file, and sharpened the end into a three sided awl. Chuck it in a drill and go. It works better than any of the twist bits I was using, though it does need to be resharpened after each hole.

[William Fretwell]

After setting the teeth a file is run along the top of the teeth to level them, THEN they are sharpened. That is what the real engineers do!

[Luke Dupont]

After setting the teeth a file is run along the top of the teeth to level them, THEN they are sharpened. That is what the real engineers do!

Yes, that is to joint them to the same height. After that the flats must be removed otherwise there is no relief angle and the saw will be dull.

I probably should joint them as you mention though just to make sure they're all the same height after setting, since any unset teeth would protrude slightly.

I cut them very evenly all the same height as if I were jointing them, paying attention to the flats, though. I did mess up slightly on two teeth at the very end of the saw.

[Jim Koepke]

By the way, to drill the hole, I finally gave up on my worthless twist bits (even diamond bits) and took a hard, round file, and sharpened the end into a three sided awl. Chuck it in a drill and go. It works better than any of the twist bits I was using, though it does need to be resharpened after each hole.

You need High Speed Steel bits for that. One of my standard bits kind of melted trying to cut a saw plate.

A better way would be to get a hole punch. Better models have replacable dies and punches. Some come with multiple sizes.

jtk

[Luke Dupont]

You need High Speed Steel bits for that. One of my standard bits kind of melted trying to cut a saw plate.

A better way would be to get a hole punch. Better models have replacable dies and punches. Some come with multiple sizes.

jtk

Haha... I guess I need a high speed drill as well. Believe it or not I've been just using an egg beater, brace, and dremel. The dremel is underpowered and no substitute for an electric drill

I think the punch is a much better idea though. I was already thinking along those lines and wondering if there is something like those paper hole punches, but for metal.

What sort of thing do you have in mind? Preferably something small and hand powered, whilst still up to the job. I did a bit of googling and found a few things, but don't know what I'm looking at / what would be able to handle very thin, but hardened steel:

Would this sort of thing work?
https://www.amazon.com/XMHF-Round-Pu...%2C242&sr=8-36

Or do I need something beefier?

[Luke Dupont]

Bit of an update:

I have both blades made and set now. I just need to find time when the baby isn't asleep to film and do the test.

My initial impressions, without having done a scientific test, though, are:

1. There's not much difference in speed that I can tell as of yet, just having used them both fairly briefly
2. The saw with unset teeth seems to be slightly smoother and more relaxed, whilst the saw with all teeth set seems to be a little more grabby. Whether this translates into any measurable difference or not, I will find out.

One thing I did find is that my saw, especially with this shorter, narrower stretcher that I'm using for these new short blades, is actually a little bit too light. With the blade angled at 45 degrees, If I don't add any downwards pressure at all, there's no weight to the saw and so the cut barely progresses. For such a light blade to cut with no down force, I guess would require a negative rake as on Japanese saws. However, add a little downwards force and it cuts quite quickly. This is too variable for a proper test, where I want to let the weight of the saw provide a constant downwards pressure, so I'll have to see if this is any better with the blade turned parallel with the frame. If it needs more weight, I'll have to knock up a quick stretcher out of a dense hardwood.

Getting the weight of the saw frame just right, such that it's neither too heavy nor too light, takes a bit of experience for sure. Though, I imagine with skill and a strong wrist, someone used to using heavy saws may actually prefer them.

[Jim Koepke]

The punch you link to may be too small and too light weight.

My thought was something more like this > Hand Power Punch

Harbor Freight used to sell a similar if lighter model. There are other lighter ones on Amazon.

You want something that will punch the correct size holes for saw nuts or the pins you will be using.

jtk

[Luke Dupont]

Okay, I finally did a quick test. It's not scientific by a long shot, but it's good enough to tell that there is no significant difference in speed between the two blades.



Edit: In the video, my impression was that the one with raker teeth was slightly faster, but watching it again, it may be the reverse. I didn't mark the depth properly and got slightly confused as to which line I was comparing to which. If you compare apples to apples, the two blades were still nearly the same in speed -- the one with more teeth set perhaps being just ever so slightly faster.

[steven c newman]

Looks good to me.

[William Fretwell]

If you paint the front of the teeth with an enamel you will see the wear pattern for raker and regular. Using hardwood will show the difference more readily.