If you had the money, and had to replace your BT3x00...

[cabinetman]

I think for me the safety features of the SS are more than just a little compelling. The biggest thing keeping a SS out of my shop is the steep price tag on them. For the price of one SS 3HP PCS 52" fence I can have 2 Grizzly G0691s in my shop... Not saying the SS tech isn't worth extra money, but WOW that thing is EXPENSIVE...

Having said that, I wonder how long it will take me to jam $3,300.00 (roughly after taxes) in change into the piggy bank as it were...

What's the loss of a finger or three worth...or will cost you in dollars or grief?

.

[chopnhack]

In my fantasies I can regrow body parts at will

All kidding aside, even the sawstop can fail so as we learn our craft we need to research cuts we have never done before and use the vast resources at our fingertips to find safe ways of making those cuts. Whether that be jigs, sleds, using a different tool or even buying a SS, whatever gets the job done safely. I think we can use non SS saws safely just by planning ahead and using the appropriate safety devices.
I have had three kickback incidents since owning my saw - roughly 7 years and all have occurred without the blade guard - trying to resaw lumber or thickness thin or tall parts. Had I been using a different tool or correct fences there would have been no incidents. Luckily no severe injuries, just a broken push block... and mind you the bt is powerful, the push block had a 2x4 handle that the saw cracked in half when it sent it flying.

[Irv Lee]

Regrow body parts at will? see this

http://health.howstuffworks.com/human-body/cells-tissues/extracellular-matrix.htm

[dbhost]

Great post Irv! Thanks!

[dbhost]

Chop,

I totally agree, and mind you, I am in no hurry to replace my BT. I will grab a full on cyclone and replumb the whole shop before I upgrade to a SS. And while I have not heard of it happening yet, I am sure the SawStop tech CAN fail, and it should not be relied upon, like air bags in a car. (I also wish those weren't mandatory either, my wife and most of my in laws are short, and air bags are dangerous for them...).

And you have a perfectly valid point, use the proper safety equipment you have, use the proper safe techniques, and keep your head about you and all is well. It's those momentary lapses in judgement we should all have a respectful fear about...

[chopnhack]

Absolutely. Since your researching a SS, do you have any idea if the actuation of the safety mechanism does any damage to the machine? I would think with the amount of inertia that the machine has to redirect, there must be some wear occurring somewhere.

[dbhost]

A perfectly valid question, and one I don't have a good answer for. I know the brake cartridge and blade both get substantially deformed when the brake is used. I don't know about the rest of the saw. Might be a good question to direct to the SawStop people...

Any SS owners know the answer?

[big tim]

A perfectly valid question, and one I don't have a good answer for. I know the brake cartridge and blade both get substantially deformed when the brake is used. I don't know about the rest of the saw. Might be a good question to direct to the SawStop people...

Any SS owners know the answer?

It is a valid question. However one would think that after having sold thousands of saws, any potential problem as a result of the brake cartridge firing would be ready knowledge by now. I don't know how significant this is but they claim that the arbor bearing on their saw is larger (62MM) than the bearing on any other make saw.

Tim

[cabinetman]

If I had a BT, and were to replace it, I would consider a SS, but might go with another Unisaw. I've had a few, and like them. SWMBO might be making up my mind.

.

[LCHIEN]

I think if i remember correctly the brake mechanism in the SawStop is a honeycomb aluminum piece that's designed especially be fired into the rim and teeth of the blade and dissipate the rotational energy quickly by deforming the metal brake. So the brake absorbs the energy but gets destroyed (along with the blade - probably the carbide teeth are damaged beyond economical repair) in the process. The replacement parts after an "activation incident" include a new brake and a new firing cartridge. Plus a blade of course. Figure on an activation costing you $250 but if it saved a serious cut/finger amputation it probably saved you $10,000/50,000 or more in medical bills. plus possible disfigurement.

I've not seen it mentioned anywhere reports of false activations that have occurred.

Brake position vis a vis the blade


Unfired brake cartridge


Brake and blade after activation


Note the honeycomb of small holes allows blade penetration of the brake for to stop rotation. The two large holes near the brake pivot is probably there for shock absorption when the brake and blade grab, transferring energy to the brake and supported by the pivot. See how the hourglass-shaped hole nearest the pivot is completely collapsed. My guess is that any arbor damage is limited. Because the coupling to the arbor is with the nut and arbor washers which may slip under serious duress, and the belts which probably give way before the arbor washers slip, and finally the torque transferred to the arbor in an activation is no worse than locking up your blade on some pinch or knot that you would encounter in working.

[Cochese]

I think if i remember correctly the brake mechanism in the SawStop is a honeycomb aluminum piece that's designed especially be fired into the rim and teeth of the blade and dissipate the rotational energy quickly by deforming the metal brake. So the brake absorbs the energy but gets destroyed (along with the blade - probably the carbide teeth are damaged beyond economical repair) in the process. The replacement parts after an "activation incident" include a new brake and a new firing cartridge. Plus a blade of course. Figure on an activation costing you $250 but if it saved a serious cut/finger amputation it probably saved you $10,000/50,000 or more in medical bills. plus possible disfigurement.

I've not seen it mentioned anywhere reports of false activations that have occurred.

Brake position vis a vis the blade


Unfired brake cartridge


Brake and blade after activation


Note the honeycomb of small holes allows blade penetration of the brake for to stop rotation. The two large holes near the brake pivot is probably there for shock absorption when the brake and blade grab, transferring energy to the brake and supported by the pivot. See how the hourglass-shaped hole nearest the pivot is completely collapsed. My guess is that any arbor damage is limited. Because the coupling to the arbor is with the nut and arbor washers which may slip under serious duress, and the belts which probably give way before the arbor washers slip, and finally the torque transferred to the arbor in an activation is no worse than locking up your blade on some pinch or knot that you would encounter in working.

Good work there. That's the best description and visual clues I've seen about the displacement of force. Calms my concerns a bit, but there still has to be some residual force being transferred to the rest of the saw. This design seems to minimize it fairly well. I'd be interested to see in twenty years of use how the structure is holding up.

I'd hold my nose while doing it, but I might get one one day.

[cabinetman]

An activation fee (whatever it is) is definitely worth what it costs, especially if it saves you from injury. As for the cost of the saw, whatever the differential is IMO, justifies the benefits it provides. To disregard the possibilities of purchasing the saw because of it's founder doesn't make sense.

.

[tommitytomtom]

I own a 31 year old Unisaw with 52" Beisemeyer fence. It's my go-to saw at home. I have 2 BT3x00 as well. One is a parts machine. The other BT is in my smaller shop at work. If that BT goes, I'll just take work home.

[LCHIEN]

Good work there. That's the best description and visual clues I've seen about the displacement of force. Calms my concerns a bit, but there still has to be some residual force being transferred to the rest of the saw. This design seems to minimize it fairly well. I'd be interested to see in twenty years of use how the structure is holding up.

I'd hold my nose while doing it, but I might get one one day.

Like I said, the force transferred to the arbor is probably no more than if you locked up the blade while cutting something that closed up around the blade.

[Cochese]

Like I said, the force transferred to the arbor is probably no more than if you locked up the blade while cutting something that closed up around the blade.

Perhaps. I do find it interesting that their website has no mention of durability studies.