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View Full Version : Riving Knife for Jet Super Saw



Mike OMelia
11-18-2008, 12:28 AM
OK, I have not studied the mechanics of the saw well enough yet, but I am wondering if a true riving knife mod is out there. It would be SOOOO much better than the splitter. For so many reasons! Anybody know?

Mike

Mike OMelia
11-18-2008, 9:29 PM
I thought this would get some response! I looked at the mechanism for lowering and raising the blade. There does look to me to be a way to do this. Is there a reason NOT to do this?

With the fact that riving blades will become required for UL certification, you would think people would be looking into this, especially those with shops that are specifically insured. Insurance companies may require riving knives which would force people to buy new saws. Perhaps the idea? Sorry for sounding cynical, but it does appear (at least for my saw) that adding a riving knife is a possibility.

Mike

Jamie Buxton
11-18-2008, 10:53 PM
I looked at the exploded drawing in the owners manual. This saw appears to raise and lower by pivoting around an axle in front of the blade. This is how almost all table saws in the US have been designed. Their manufacturers have argued that it is impossible to put a true riving knife on these saws. They've designed completely new saws to meet the riving knife regulation.

Gary McKown
11-19-2008, 10:36 AM
Are you familiar with the "ripping knife" mod done on a Grizzly 1023SL? Last I heard he was working on one for the Unisaw, too. Search for BacsiBob on Woodnet.

John Ricci
11-19-2008, 7:36 PM
I looked at the exploded drawing in the owners manual. This saw appears to raise and lower by pivoting around an axle in front of the blade. This is how almost all table saws in the US have been designed. Their manufacturers have argued that it is impossible to put a true riving knife on these saws. They've designed completely new saws to meet the riving knife regulation.

I have the General 650R. The saw was shipped with a manual for a 650 with a page showing the additional parts used to fit the riving knife. There is a bit of extra machining that they did using the 650 parts to make the new saw with the knife. Here is a link to the 650R manual that shows how they did it...look at the exploded view on page 24.

http://www.general.ca/manuel/650R-T50_EN.pdf

I took a few pics of the inside of my saw which may help. You can see where the standard 650 parts were machined and extra bits added. Old saw with mods, and it works just great.

J.R.

Jamie Buxton
11-19-2008, 7:55 PM
I have the General 650R. The saw was shipped with a manual for a 650 with a page showing the additional parts used to fit the riving knife. There is a bit of extra machining that they did using the 650 parts to make the new saw with the knife. Here is a link to the 650R manual that shows how they did it...look at the exploded view on page 24.

http://www.general.ca/manuel/650R-T50_EN.pdf

I took a few pics of the inside of my saw which may help. You can see where the standard 650 parts were machined and extra bits added. Old saw with mods, and it works just great.

J.R.

Wow. This is worth a separate post, John. That does seem to be the holy grail. What I think I'm seeing is an L-shaped arm (#57 in the drawing) which pivots around the blade's axle, driven a pin (#58) in the main casting. If the curve of the slot in the arm is just right, the end of the arm moves up and down just right to be a true riving knife. Is that right? And can I have one as a retrofit on to my Unisaw? :o

John Ricci
11-19-2008, 8:09 PM
Wow. This is worth a separate post, John. That does seem to be the holy grail. What I think I'm seeing is an L-shaped arm (#57 in the drawing) which pivots around the blade's axle, driven a pin (#58) in the main casting. If the curve of the slot in the arm is just right, the end of the arm moves up and down just right to be a true riving knife. Is that right? And can I have one as a retrofit on to my Unisaw? :o

Yep, that pretty much covers it. I suppose it could be done to any saw with the additional parts to carry the riving knife and a bit of work from a machine shop. Its hardly what I would call a total re-design and it does tackle the problem rather elegantly:cool: Only in Canada eh!

J.R.

Mike OMelia
11-19-2008, 11:12 PM
If you look closely at the Supesaw raising mechanism, it is a flat iron plate with 4 bolts through it. There is NO question that a blade could be attached. And, I intend to prove it. If I am wrong, I will admit it. The only problem I see is that the zero clearance plate might need to be modified to make room for the knife. My guess is that adding a knife to an existing saw does not solve UL certification and insurance requirements. Plus saw makers get to sell more saws. After all, its just business. But, after all, its my hand.

Mike

PS: Thanks for the bolt on knife link... it only further proves my point. All saw owners should be able to benefit from safety advances without going broke doing it.

Mike OMelia
11-27-2008, 3:50 PM
Just saw the article in the Winter FWW on Riving Knives. Still, you'd think someone would ask the question about add-on riving knives.

Mike