SawStop Service

[Packard]

I read about Saw Stop back in the late 1990s.  The inventor had shown it to all the major saw manufacturers and could not sell the idea. He got some financing and started to make his own saws. 

This was a guy who thought he had a way to save limbs.  No one was with him.  I give him an A+ for persistence. 

Similar was the Mercedes Benz invention on how to prevent reclining seats to collapse in an accident. (It happened to me in my 1987 Audi Quattro.  I got rear ended, and it collapsed the seat to the flat condition and drove my head into the rear seat.  The doctor said I was lucky.).

At any rate, Mercedes offered the patent for free to any car manufacturer who wanted to use it.  It added about $10.00 to the cost of the car.  They had no takers.

Mercedes was not being entirely altruistic.  Their lawyers probably told them that since the technology was available to them—they developed it—if someone got injured because they left it out the payout would be huge.

So they added $20.00 cost to every car they produced.  They wanted all their competition to have the same cost burden.  No takers.

So Saw Stop probably assumed that once they were on the market with the safety saw, that all the competition would want to jump into the pool too.  So Saw Stop had to produce a quality saw that cost more than the competition.  Safety is not always a competitive edge in the market place.

 

[Mini Me]

For me it was the way he prevented other companies developing alternative safety systems and I thought that was the big problem. Volvo who invented the seat belt we use today gave away the IP for free and if they hadn't it would have set back passenger safety many years.

 

[Cheese]

Ya, not exactly one of my favorite people...it was about the buck, always was and still is. The altruistic statements ring hollow and the truth behind the latest patent offer is still open to questions. After shaking hands...make sure you still have 5 fingers.  [smile]

 

[Packard]

Ya, not exactly one of my favorite people...it was about the buck, always was and still is. The altruistic statements ring hollow and the truth behind the latest patent offer is still open to questions. After shaking hands...make sure you still have 5 fingers.  [smile]

The only accidents I have had on the table saw involved kickbacks in the form of a kick-up.  I’m self-taught in woodworking, relying on books and magazines and more recently the Internet.

Avoiding the moving blade is intuitively dangerous.  But cutting very short rips is not.

Saw stop would not have helped me.

I do wonder if people using Saw Stop are as careful around the blade as those who do not have that tech.  Or is the sense of safety makes them complacent about the spinning blade.

 

[Tom the Remodeler]

Ya, not exactly one of my favorite people...it was about the buck, always was and still is. The altruistic statements ring hollow and the truth behind the latest patent offer is still open to questions. After shaking hands...make sure you still have 5 fingers.  [smile]

The only accidents I have had on the table saw involved kickbacks in the form of a kick-up.  I’m self-taught in woodworking, relying on books and magazines and more recently the Internet.

Avoiding the moving blade is intuitively dangerous.  But cutting very short rips is not.

Saw stop would not have helped me.

I do wonder if people using Saw Stop are as careful around the blade as those who do not have that tech.  Or is the sense of safety makes them complacent about the spinning blade.

Hi Packard,

You bring up a great illustration of how/where the table saw is often misunderstood, calibrated, and/or utilized.

I'll make the obligatory observation that a bandsaw does not suffer from the behavior you describe as the blade is only ever descending through the wood. In fact, one could rip half the length of the board, walk away for a cup of coffee, and return 15 minutes later with the board where he/she left it.

In terms of table saws, I often see people (usually YouTubers) talking about "squaring the blade to the miter slot", "aligning the fence to the miter slot", etc.... Assuming that they mean "perfectly parallel to the blade", this seems foolish, if not downright unsafe.

My understanding and experience is that the proper way to dial in a machine is for the controlled/keeper/trapped wood to only interact with the descending teeth of the circular blade, and should not interact with the ascending teeth. This is accomplished by having the blade very slightly toed-in relative to the miter gauge/slider, and have the rip fence toed-in the other direction. This necessarily means that the miter fence and miter slot should not be parallel. I usually aim for a toe-in of ~0.15mm over ~300mm, measuring off the edge of the same carbide tooth.

Regarding hand position, I would make the gentle suggestion that if a machine operator is using their machine in a manner where they might experience an injury if their wood kicks back, binds, splits, explodes, or otherwise acts in an unanticipated manner, then they would benefit from a thorough review of their operations and procedures. I see too many table saw operators rely on push sticks, hand pressure, and/or careful concentration to avoid an injury. I'm a big fan and proponent of power feeders, pneumatic clamps, sleds and carriages.

 

[Michael Kellough]

Tom said “My understanding and experience is that the proper way to dial in a machine is for the controlled/keeper/trapped wood to only interact with the descending teeth of the circular blade, and should not interact with the ascending teeth. This is accomplished by having the blade very slightly toed-in relative to the miter gauge/slider, and have the rip fence toed-in the other direction. This necessarily means that the miter fence and miter slot should not be parallel. I usually aim for a toe-in of ~0.15mm over ~300mm, measuring off the edge of the same carbide tooth.”

If you have adjusted the saw properly as above then you can’t simply use a square to make the blade square to the table surface and expect your cuts to be perfectly square. The resulting cuts will be very slightly off 90* since the blade is round. More apparent the taller the workpiece.

 

[Birdhunter]

With a SawStop, I usually have the stock on the right for rips and on the left for cross cuts. My practice is to position my body away from the line of flight for a cutoff. I will go to great lengths to keep my hands well way from the blade. I’ve learned to trust my gut. If I am the least uncomfortable with an operation, I will back off and find a way to achieve the results in a way that I am totally comfortable with. The presence of the safety device doesn’t decrease my safety awareness. I value the safety device, but I don’t depend on it.

 

[smorgasbord]

Tom said “... I usually aim for a toe-in of ~0.15mm over ~300mm, measuring off the edge of the same carbide tooth.”

If you have adjusted the saw properly as above then simply use a square to make the blade square to the table surface and expect your cuts to be perfectly square. The resulting cuts will be very slightly off 90* since the blade is round. More apparent the taller the workpiece.

To put a number on it, the angle Tom's talking about is ATAN (0.15/300), which is 0.029º, which is about an order of magnitude better than than accuracy of the digital inclinometers that it seems almost every woodworking YouTuber uses to set blade angle. And practically speaking, there's the question of how well the teeth are aligned/ground and the blade probably deforms at least that amount when cutting wood, especially the thick pieces that might let you measure that angle.

Personally, I'd be really happy with that kind of slot to blade alignment.

 

[Tom the Remodeler]

Tom said “My understanding and experience is that the proper way to dial in a machine is for the controlled/keeper/trapped wood to only interact with the descending teeth of the circular blade, and should not interact with the ascending teeth. This is accomplished by having the blade very slightly toed-in relative to the miter gauge/slider, and have the rip fence toed-in the other direction. This necessarily means that the miter fence and miter slot should not be parallel. I usually aim for a toe-in of ~0.15mm over ~300mm, measuring off the edge of the same carbide tooth.”

If you have adjusted the saw properly as above then simply use a square to make the blade square to the table surface and expect your cuts to be perfectly square. The resulting cuts will be very slightly off 90* since the blade is round. More apparent the taller the workpiece.

Hi Michael,

In principle I agree with your observation, but in practice I would argue that it's irrelevant for woodworking.

I double checked my notes from my last calibration, and the toe-in on my slider is 0.05mm over 280mm, with the blade at its maximum height of 94mm. So, at the mid-point of the blade, the toe-in is reduced to 0.025mm over the 94mm height. Or, in King's measurements, that's 0.001" out of square over 3.7". Assuming most 10" table saws are limited to a ~3" cutting height, that brings the discrepancy to 0.0008" from top to bottom. Cutting parts for, say, a cabinet face frame or frame and panel doors out of 3/4" thick stock would leave the parts out of square by 0.0002" over the height of the stock.

All of the above assumes that the blade is truly square to the table in the vertical axis, I suspect that most users who are tilting their blade and returning to plumb are rarely nailing a true and perfect 90 degree registration anyways. If a user was really concerned, they can always adjust the blade tilt by a couple minutes to allow for the discrepancy.

All of this assumes a sharp, clean, flat blade, with the work properly clamped to a carriage or fed by a power feeder. As soon as you start introducing miter gauges and using one's fingers as clamps, or push blocks for ripping, all of this flies out the window because there's almost no way to account for all of the inconsistencies introduced by the user.

 

[ChuckM]

Hahaha. Dr Gass must be finding it amusing that even after his business was sold, the topic of SawStop never stops generating discussions in woodworking forums.

About the question whether the technology emboldens a table saw user or changes their behavior on the table saw. Speaking for myself (an user of an ICS or a PCS since 2006 or so), the answer is no. It has never happened to me, but every trigger of the finger-saving feature could be quite a hit: A WWII blade plus the cartridge ($139. Darn. I should get a spare one when it was under $60!). In fact, because of that financial implication, believe it or not, I need to be more careful with the setup than before, making sure no metal of any kind (the miter gauge, for example, or any jigs with a metal part) would be in contact with the blade during any ripping or cross cutting operation. For new, complicated stuff, I may even make a mock-up pass before turning the switch to the ON position.

Touch wood. I have never had to use the safety feature of the SawStop or the airbags of my vehicle.

 

[Michael Kellough]

Don’t want to use the space to quote Tom from #28 but I agree, what I posted about is a vanishingly small amount/difference that very few people will ever discover and no one really needs to be concerned with.

 

[Packard]

[…]I need to be more careful with the setup than before, making sure no metal of any kind (the miter gauge, for example, or any jigs with a metal part) would be in contact with the blade during any ripping or cross cutting operation. […]

I’ve cut aluminum with impunity on my table saw, chop saw and radial arm saw.  But this Saw Stop I would not be able to do that?

 

[Packard]

Ya, not exactly one of my favorite people...it was about the buck, always was and still is. The altruistic statements ring hollow and the truth behind the latest patent offer is still open to questions. After shaking hands...make sure you still have 5 fingers.  [smile]

The only accidents I have had on the table saw involved kickbacks in the form of a kick-up.  I’m self-taught in woodworking, relying on books and magazines and more recently the Internet.

Avoiding the moving blade is intuitively dangerous.  But cutting very short rips is not.

Saw stop would not have helped me.

I do wonder if people using Saw Stop are as careful around the blade as those who do not have that tech.  Or is the sense of safety makes them complacent about the spinning blade.

Hi Packard,

You bring up a great illustration of how/where the table saw is often misunderstood, calibrated, and/or utilized.

I'll make the obligatory observation that a bandsaw does not suffer from the behavior you describe as the blade is only ever descending through the wood. In fact, one could rip half the length of the board, walk away for a cup of coffee, and return 15 minutes later with the board where he/she left it.

In terms of table saws, I often see people (usually YouTubers) talking about "squaring the blade to the miter slot", "aligning the fence to the miter slot", etc.... Assuming that they mean "perfectly parallel to the blade", this seems foolish, if not downright unsafe.

My understanding and experience is that the proper way to dial in a machine is for the controlled/keeper/trapped wood to only interact with the descending teeth of the circular blade, and should not interact with the ascending teeth. This is accomplished by having the blade very slightly toed-in relative to the miter gauge/slider, and have the rip fence toed-in the other direction. This necessarily means that the miter fence and miter slot should not be parallel. I usually aim for a toe-in of ~0.15mm over ~300mm, measuring off the edge of the same carbide tooth.

Regarding hand position, I would make the gentle suggestion that if a machine operator is using their machine in a manner where they might experience an injury if their wood kicks back, binds, splits, explodes, or otherwise acts in an unanticipated manner, then they would benefit from a thorough review of their operations and procedures. I see too many table saw operators rely on push sticks, hand pressure, and/or careful concentration to avoid an injury. I'm a big fan and proponent of power feeders, pneumatic clamps, sleds and carriages.

Those yellow (plastic) push sticks are dangerous.  If you just catch the blade it can hook up and bend the push stick until the push stick can no longer absorb any further energy and explode.

A similar push stick in wood is far safer.  The blade chews it up, but the stick never stores any energy that can hunt out softer parts of your body. 

I do have a yellow plastic push block that I am very reluctant to use.  If it stores up any energy it has enough structure to pass all of it to my hand holding it.    It also fails because the rubber pads that are to hold the stock can get covered with saw dust and they no longer have enough friction to do the job.

 

[rmhinden]

I’ve cut aluminum with impunity on my table saw, chop saw and radial arm saw.  But this Saw Stop I would not be able to do that?

Yes, you can cut aluminum.  There is an override to turn off the detection mechanism. 

I have used it a few times.

Bob

 

[ChuckM]

[…]I need to be more careful with the setup than before, making sure no metal of any kind (the miter gauge, for example, or any jigs with a metal part) would be in contact with the blade during any ripping or cross cutting operation. […]

I’ve cut aluminum with impunity on my table saw, chop saw and radial arm saw.  But this Saw Stop I would not be able to do that?

You can, but you first need to consciously use a key to turn off the safety feature, such as when dealing with wet wood or materials containing metal elements. Small bits like staples often found on construction lumber, though, won't trigger the SawStop (but it's best to check for metals on any lumber beforehand as a precaution),

 

[Packard]

From my experience, band saw cuts are never as smooth as table saw cuts.  So band saws have an uphill journey to replace table saws.

Hi Packard,

I 100% agree with you that, generally, a table saw will produce a better quality rip cut than a bandsaw.

I will also make the follow-up observation that, depending on what you're doing, the above observation is generally irrelevant, as most projects involve several post-ripping operations such as jointing, planing, routing/shaping, drum/widebelt sanding, etc... So, unless you're processing plywood/sheet goods, the quality of the rip cut will often be irrelevant.

In the case of sheet goods, it has been my experience that a well-tuned track saw with a sharp blade and TSO parallel guides will produce a better cut on plywood than trying to safely handle a sheet of plywood on a cabinet saw. Most cabinet saws lack a scoring blade, whereas many modern track saws have some facility for pre-scoring shot goods with delicate surfaces which are prone to chipping.

I have a colleague with whom I am consulting as he is planning out a semi-retirement shop. He started with the idea that the table saw is the "Heart of the Shop", but once we reviewed his needs and planned work, we could not come up with any operation or task that required a table saw. Break down sheets of plywood? Track saw. Rip wide or narrow strips of solid lumber? Bandsaw, then a finish pass on the jointer/planer, or router table/shaper with offset fence. Precision crosscuts? Miter saw, bandsaw, MFT/3, etc.... Dados and/or dovetails? Freehand router with jigs or router table.

All of which is to say that the traditional cabinet table saw can perform a lot of tasks, but it doesn't perform any of them particularly well when compared to other machines. Again, a sort of "jack of all trades, master of none" that, by the way, occupies a big shop footprint and can be very expensive.

My table saw, with a new blade and a fresh zero clearance insert will almost match the quality of the cut on plywood that my track saw yields.  But it is not nearly as good as the track saw on melamine clad particle board. 

In fact, for face frame cabinets it does not really matter.  But as I am moving towards Euro cabinet (no face frame) construction, it does really matter.

As for safety, I have a horizontal band saw that I use for cutting steel bar. I can turn it on and begin the cut and come back 5 minutes later to turn it off.  Very safe.  But not a wood working device.

I designed a couple of simple wood toys that I thought I could move from the scroll saw to the band saw.  But my totally inadequate band saw lacks the torque to slice through 3/4” pine board, and the guides don’t guide.  So a disappointment.  I should have bought a better tool.  But it rarely gets used, and more rarely because it is inadequate.