24 degrees rake angle?

[GLFaria]

I have the plate of what was once a quite ordinary gents saw, 10" long, .5mm thick, 13tpi, filed rip, set from origin at 1mm, which I want to put to use.

On looking closely the rake angle seemed somewhat high - actually at first sight I thought, "heck, 30 degrees!", so I took a macro picture and measured the rake on several teeth. It is 24 degrees.

I searched a bit in my books and in the net and this does not seem usual at all, even though I found several references of up to 20 degrees, and I seem to recall one (but just one) mentioning up to 25 degrees.

What kind of work are 24 degree raked, rip filed teeth used for?

 

[Corneel]

Slow work.

 

[Cheshirechappie]

Mitre saws (the huge backsaws made for use with mitre boxes) were sharpened with 25 degree rake, and about 30 degrees fleam. Presumably, this gave a clean cut when mitering mouldings. Perhaps your little gent's saw is intended for similar work on beadings and small mouldings; I'm not sure why the rip teeth, but as they're relatively small, perhaps the sharpener felt that there wasn't much to be gained by adding fleam.

 

[bugbear]

Anyone know the angles for "peg teeth"?

BugBear

 

[Jacob]

.... I'm not sure why the rip teeth, but as they're relatively small, perhaps the sharpener felt that there wasn't much to be gained by adding fleam.

Any smaller than about 10 tpi and there isn't much advantage in fleam and in any case the smaller the teeth the harder it is to achieve.

 

[Cheshirechappie]

Anyone know the angles for "peg teeth"?

BugBear

Not certain, but I think it's 30 degrees rake (so the teeth are in effect a row of equilateral triangles with one side on the base of the toothline) with a bit of fleam.

 

[GLFaria]

Slow work.

Now that's my kind of work!!! :wink:

And what may "peg teeth" be?