Woodworking Talk banner
21 - 28 of 28 Posts

·
where's my table saw?
Joined
·
29,992 Posts
I wrote several responses, but let them die. I did understand your previous post, and I did see the part about the workpiece being trapped.

After thinking about it for several days, I believe that the fundamental difference between our points of view are our concepts of the blade forces at that first instant when the workpiece lifts up.

I concede that @woodnthings may be correct, but I'm still not 100% sure about it. (I reserve the right to say in the future, "the jury will disregard this post." :)

MY VIEW:
In my view, the direction of force from the back of the blade to the workpiece is mostly vertical at the start of the kickback. There is isn't a lot of horizontal force (yet) to eject the workpiece underneath the angled blade. As the workpiece lifts, it has to "get outa' there" but the workpiece must lift up more to reach the point where the curved blade is introducing sufficient horizontal force to eject the workpiece in a kickback.

With a bevel cut, the blade is raised more than a typical 90 degree rip cut. Whether that's enough to reduce the horizontal force such that there is a compression/pinching issue above the workpiece (at the start of the kickback) is an open question for me.

WOODNTHINGS' VIEW (FROM MY PERSPECTIVE):
I think that woodnthings is thinking about a lower blade, where the forces at the rear of the blade are much more towards the front of the saw, and much less upward than my point of view. Imagine a blade so low that the teeth are barely above the workpiece. Most of those forces want to push the workpiece towards the front of the saw, perhaps enough to eject the board out from under the trapping effect of the angled blade.

-> Woodnthings: Does that match your perspective? Does it help? Am I on track, or still missing something?
No, I never use a low blade. The gullets should show when ripping and be at least 1/4" or more above the work. A low blade may work OK on a crosscut, but I set the height so the gullets show there also.
A high blade will tend to press the work down in front, but may also tend to lift it up at the rear. It all depends on the set of the teeth and the rake angle.
There is just no way to know what will happen unless a test is done of all the possibilities.
Rick Christopherson claims he has done this and nothing happens. I trust his opinion. but I still wouldn't trust my saw and blade in a "trapped" workpiece situation.
It's just not worth finding out and possibly having a bad result for me.
I would never use the tilted blade into/towards the fence, right tilt or left tilt, it wouldn't matter.
 

·
Premium Member
Joined
·
2,263 Posts
One thing not mentioned about bevel cuts is the material must be held flat against the table for an accurate cut. Obviously that requires either and hand held device, or a featherboard clamped to the fence. Not to mention, starting with flat material, but we all know flat is relative in ww’ing.

It‘s easy to picture a limitation with a right tilt when the keeper piece is under the blade bevel. For example, a 16” wide length of wood, fence to right, blade tilted to right, there is no good way to maintain down pressure against the table all the way to the blade plate. Maybe it’s not a big deal, but I had this issue myself.

However with a left tilt you can easily maintain down pressure against the table. And, of course on a right tilt this would be true if the width allows fence to left on a right tilt.

But as someone said, how many times do we do bevels on a table saw?

On another point, there is a technique for getting around a situation by clamping a straight edge to the bottom of a board and registering that against the side of the table, essentially clamping a fence to the work piece. Of course this assumes the table edge is parallel to the blade.
 

·
Premium Member
Joined
·
2,263 Posts
When I walked into a real shop I learned how pros work.
I’ve seen some “pros” put out work I wouldn’t put my name on. But they did it 5x faster and if they made $1 on it they made more than me.

I wish non-ww’ing people appreciated my work more, rather than say “oh that’s nice, hey did you hear the Gators fired the coach?”
 

·
Registered
Termite
Joined
·
5,963 Posts
I’ve seen some “pros” put out work I wouldn’t put my name on. But they did it 5x faster and if they made $1 on it they made more than me.

I wish non-ww’ing people appreciated my work more, rather than say “oh that’s nice, hey did you hear the Gators fired the coach?”
Agree. And I've seen hobbyist get more credit than there work was worth.. it's easy to make good or bad comments.

I believe you asked me one time how I got into furniture making.. Not with a negative attitude.

So I wouldn't go there with pro/ hobbyist work comparisons...
 

·
Registered
Joined
·
5,056 Posts
No, I never use a low blade. The gullets should show when ripping and be at least 1/4" or more above the work. A low blade may work OK on a crosscut, but I set the height so the gullets show there also.
A high blade will tend to press the work down in front, but may also tend to lift it up at the rear. It all depends on the set of the teeth and the rake angle.
There is just no way to know what will happen unless a test is done of all the possibilities.
Rick Christopherson claims he has done this and nothing happens. I trust his opinion. but I still wouldn't trust my saw and blade in a "trapped" workpiece situation.
It's just not worth finding out and possibly having a bad result for me.
I would never use the tilted blade into/towards the fence, right tilt or left tilt, it wouldn't matter.
I agree with Rick that it can be done and nothing will happen as long as the wood is flat and it is also straight edged on the fence side. ... AND the blade and fence are well aligned, ... AND the wood stays flat and registered against the fence throughout the cut. ... AND the wood does not move or pinch (much) during the cut. In other words, the cut must go perfectly right. Furthermore, the push block or stick must have enough space to operate safely and effectively, and it must protect the table saw operator. (I suppose if you're comfortable with making cuts this way often, you could be using a push stick. I wouldn't, but I wouldn't make this cut in the first place, either.)

Any slight deviation from those strict requirements in the previous paragraph is the concern, of course. Without data to back it up, I assert that any slight deviation from the "perfect cut" requirements in my previous paragraph is inherently much more risky and dangerous in a "trapped wood bevel rip cut" than other rip cuts where the blade does not angle towards the fence.

As I have repeatedly said, I don't make those cuts and never plan to. Instead, I move the fence to the other side of the blade and make the bevel cut very carefully, avoiding the issue altogether.
 

·
Premium Member
Joined
·
2,263 Posts
So I wouldn't go there with pro/ hobbyist work comparisons...
If this means only a pro can do professional work, I take extreme exception to that idea.

We all know of and respect your experience and I take no offense, but for others I say your tendency to be disdainful of hobbyists serves no purpose.

The fact is, there some extremely talented people out there, even on this forum and their work would surpass many “professional” furniture makers.

We are here to share knowledge, show our work, and engage in some friendly debate.

Take a look in the back of a Fine Woodworking magazine.
 
21 - 28 of 28 Posts
Top