Saw Stop

[Ruffles]

For anyone like me that's scared witless by circular saw tables the Saw Stop seems an amazing bit of technology for preserving fingers. I'd love to know how it it differentiates flesh from timber?

 

[BrendanS]

It passes an electrical current through the blade, and when anything other than wood touches the blade, and changes the electrical signal at the detectors, it shoves an aluminium piece into the teeth of the blade to stop it instantly.

Details here
http://www.sawstop.com/how-it-works-overview.htm

Video of how it works here
http://www.sawstop.com/media/WMV/Stephen.htm

Amazing technology!

 

[Ruffles]

I guess it rather depends on how often it fires incorrectly - and how much the cartridges cost. It says you can override it for damp timber.

 

[BrendanS]

About $90 for a cartridge, and $110 for a new blade, so roughly $200 after a brake stop. And it's more expensive than a standard saw table in the first place. A quick search seems that they are selling into schools and technical colleges, where an injury could cost them a fortune in personal injury claims and increased insurance policies in the US. Not sure they will sell that many to home DIY users here.

 

[jon]

Very impressive, surprised no guard over the blade though, different regs over there I guess. Next a quick stop router when table mounted? That might prevent me from shortening my digits any more.

 

[old_salt]

It could have an application on a planner as well they will take your fingers ends off before you know it.
A close friend suffered this experience 3 months ago and is now making a good and positive recovery thank goodness but it has delayed the progress on his boat some what.

As to destroying the blade surly with some engineering development the rotation could be stopped an other way.
I have in the past fitted auto stops to Radial Arm Drills and Milling machines as long ago as 1969 in that day they relied on a mechanical interference to activate an electrical reverse action of the windings in the motor so this is not a new thing. But non the less a very worthy development in the DIY industry lets hope some one takes it up over here.

 

[doug748]

As you are scared witless you will probably be ok. Thanks for pointing out the site, I have added it to my list.

 

[graham]

I wonder who got picked to stick a finger in and test it? /forums/images/graemlins/shocked.gif

 

[DinghyMan]

Remember using a very large radial drill many years ago when an apprentice drilling and tapping 3ft cast blanking plates - it had a device like a car aerial that extended downwards from the side of the bit holder and you put it into one of the holes around the side of the casting and drilled & tapped away, any movement, which could be fun on a large valve body, and the machine stopped immediately with no damage.
Also remember turning cast rings on a bonus system and having them exploding whilst being turned - you just stood well to one side when turning then overspeed.

Didn't have health and safety back then - you used apprentices for these sort of jobs...

 

[DownWest]

The tester used a sausage, only nicked it. Also it doesn´t always trash the blade. Price wise, it compares to a good quality bench saw and was deemed to be as well made. Wooden Boat did the test a couple of years ago.
Andrew

 

[old_salt]

Hi DinghyMan.
Yes that sounds like the device it was very effective and saved a lot of injury's in the machine shop at "Edward Woods" Manchester a little famous then for the cantilever stand at Manchester united in 1968.