Delta Unisaw safety

Keye

Keye
Corporate Member
I have been reading a number of threads about TS safety. I was planning on doing something soon. Soon is here after what happened Sat. I was cutting tapers on some small table legs. The leg started to bind and move up off the TS top. Thank goodness for the panic board hanging in front of the off switch. I hit it with my knee to cut the TS off immediately. I stood there for a while visualizing the leg plugged into my head.

Bought the TS in the early 90's. The closest I had come to owing a woodworking tool at that time was a circular saw. The blade guard was cheap and a pain so I took it off. This is the way I have used it every since then.

I have tapered at least 60 table legs over the years without a problem. I still can not figure out why this one started to bind.

I guess I am asking what I can and should do to "this" saw to make it safer. I am going to trash the jig I have been using. I learned from a thread last week the jig I am using is not considered safe.
 

tvrgeek

Scott
User
Could be the wood internal stresses binding.
As you don't have a riving knife, by all means, add a splitter. DIY or an MJ.
I tried one of those simple hinged taper jigs. Scared the hell out of me, so I will only do a taper on a sled where the work is firmly clamped. It also lets me stand right of the blade and work.

Never used the OEM blade guard on my old contractor. Rarely used the factory splitter. 90% of the time, I used a ZCI with an MJ splitter. Only bevels and dados did I do without. I have been attempting to get used to the blade guard on my new saw. Verdict is still out, but the riving knife is great.

I keep a couple cedar shims within reach if I see a bit of wood closing up.
 

HMH

Heath Hendrick
Senior User
I've got a mid 90's vintage Unisaw myself, and in setting up shop at my new home, have been going back through everything, taking may time, and getting all of may larger stationary tools dialed-in, etc. That said, for my uni, I've been in the same boat as you before, but just bought the riving knife/ blade guard package from Lee Styron/ Shark Guard, (they offer a B.O.R.K - Bolt On Riving Knife) package for the Uni's, that is really impressive - I'd recommend checking it out.
 

Keye

Keye
Corporate Member
Could be the wood internal stresses binding.
As you don't have a riving knife, by all means, add a splitter. DIY or an MJ.
I tried one of those simple hinged taper jigs. Scared the hell out of me, so I will only do a taper on a sled where the work is firmly clamped. It also lets me stand right of the blade and work.

Never used the OEM blade guard on my old contractor. Rarely used the factory splitter. 90% of the time, I used a ZCI with an MJ splitter. Only bevels and dados did I do without. I have been attempting to get used to the blade guard on my new saw. Verdict is still out, but the riving knife is great.

I keep a couple cedar shims within reach if I see a bit of wood closing up.
The hinged jig has now scared the heck out of me, it is gone. I am thinking about using the BS to cut tapers, more sanding but not a big deal. Is this idea dumb.
What is an MJ?
 

FredP

Fred
Corporate Member
The hinged jig has now scared the heck out of me, it is gone. I am thinking about using the BS to cut tapers, more sanding but not a big deal. Is this idea dumb.
What is an MJ?
Micro jig.
I use a sled with hold downs.
 

Charles Lent

Charley
Corporate Member
Not too long ago Amazon was selling the original Delta Pop-up splitter, but I just searched and it doesn't seem to be available any longer.
Amazon.com: DELTA 34-868 Bracket and Splitter Assembly: Home Improvement (The photo shown is of it lying down and not as it should be). It attaches to the same point under the table insert that the Delta blade guard would attach. It requires you to use a 1/8" wide tooth blade when using it. I have one of these on my Unisaw that I bought from a fellow club member, and use it whenever I am ripping any solid wood and when there is a chance of the wood binding on the blade. Maybe you can search Ebay for one. When the ripping job is complete, removing the table insert then lets the pop-up splitter to be pushed back down under the insert location and then the insert re-installed.

I have one of these splitters on my Unisaw and have found it to work very well, and there is no chance of loosing it because it remains attached to the saw when not in use. It is also compatible with the Brett Guard, which I have, but it's not in use yet because I bought it from another woodworker and pieces are missing that I must fabricate before I can install it. The one that I have is designed to attach to the shop ceiling. Brett Guards were once sold by HTC, but they also no longer seem to sell them. Below is the Amazon listing for them. When attached, the pop-up splitter sits below the saw table insert, and the insert used with it has to have an extra slot behind the blade for it. To use it, all I need to do is lift the insert and then pull up on the tab handle on the top end of the splitter. Once pulled up to it's detented stop, I then replace the table insert. It comes with anti kickback pawls, which I sharpened to make them more reliable.

The Microjig splitters work quite well, and can be used with narrow kerf blades, but there is no anti kickback capability in their design and nothing to keep the board held down against the saw table. This must be provided by using either a Microjig Grripper, or a fence installed feather board. If held down against the table, there is very little chance of a kick-back anyway.

Charley


The Amazon Brett Guard listing for the arm mounted version.
 

junquecol

Bruce
User
The hinged jig has now scared the heck out of me, it is gone. I am thinking about using the BS to cut tapers, more sanding but not a big deal. Is this idea dumb.
What is an MJ?
Rockler has a video on their tapering jig. Many you tubes on building a tapering jig (sled.) One of the best ideas I've seen is to make miter bar under sized. On forward stroke, push sled into the blade, and away from blade on return stroke. If you are using hardwood for runner, you don't have to be concerned about seasonal movement, as it's already under sized. Currently in final design of my tapering sled. I'm making it wide enough to be used either left or right of the blade. For the runner, I'm using a piece of T-track, as I have a lifetime supply
 

tvrgeek

Scott
User
MJ, or Micro Jig is just a splitter. No hold down. I used a feather board.
MicroJigs can be bought and configured for thin or wide, and can be adjusted for small offsets. I found it does not take much to keep the work from catching a tooth.

For my new saw, I attached a T-track so I can continue to use a feather board until I pay the big bucks for Jassem hold downs. As far as kick back pawls. I believe they are useless. The force of a real kickback will bent any of them into a pretzel. The idea is to not have a kickback in the first place.

Microjig gripper is a nice push block. That's all. It does not hold the wood down, you do. It is a bit small and puts you right over the blade. I don't like at all some of the uses they show. I won't be right over the blade pushing down no matter what!

A splitter is different from a riving knife. The big difference, and the one that drove me to buy a new saw, is the riving knife is about 1/4 inch behind the blade at all times. I had a small piece turn BETWEEN the blade and splitter. Second is that it is just below the blade, so you don't have to remove it for non-through cuts. You do remove it if you use a smaller blade as some do for precision or a dado. I guess one could make a knife that fits a small blade if that was your SOP setup. Or if using a splitter, make an insert with the splitter close to the smaller blade slot. When the wood wants to close up noting beats a wedge in the far open end. Wood can still bind on the splitter. Better than the blade, but still a problem. Some suggest a pin for a splitter to reduce the binding.

The over-arm unit as mentioned above may make a fine blade guard or dust collector, but has nothing to do with a splitter or knife. The above mentioned Delta splitter is just that, a splitter so it's distance to the blade is too large and it is only for through cuts. Better than nothing, and would have prevented the near miss I had on the Ridgid where thin stock went UNDER the splitter.
 

tvrgeek

Scott
User
Rockler has a video on their tapering jig. Many you tubes on building a tapering jig (sled.) One of the best ideas I've seen is to make miter bar under sized. On forward stroke, push sled into the blade, and away from blade on return stroke. If you are using hardwood for runner, you don't have to be concerned about seasonal movement, as it's already under sized. Currently in final design of my tapering sled. I'm making it wide enough to be used either left or right of the blade. For the runner, I'm using a piece of T-track, as I have a lifetime supply
Sloppy miter bar? Sounds like a good way for a sloppy cut, burn or catch. No. Make it snug. Push the work/sled through clear of the blade.
 

bob vaughan

Bob Vaughan
Senior User
I went to a piece of plywood, miter bar underneath, and a couple of good Destaco clamps years back after the cut went south on a couple of tapering jigs. Having the stock clamped down on a sliding table is far safer and more accurate.
 

zdorsch

Zach
Senior User
Like Keith I installed the shark guard. The riving knife is always on and has been a nice addition to my Unisaw. The riving knife is “manual” meaning that it does not raise with the blade—but I’ve gotten used to that and it’s not an issue now.

When I get my dust collector hooked up again I will use the rest of the shark guard for overhead dust collection.

 

tvrgeek

Scott
User
Like Keith I installed the shark guard. The riving knife is always on and has been a nice addition to my Unisaw. The riving knife is “manual” meaning that it does not raise with the blade—but I’ve gotten used to that and it’s not an issue now.

When I get my dust collector hooked up again I will use the rest of the shark guard for overhead dust collection.

You have a splitter, not a riving knife. By definition a riving knife moves with the blade.
A very good addition.
 

HMH

Heath Hendrick
Senior User
Potato - potato gentlemen.....

The Shark Guard splitter/ riving knife/ slightly less than kerf thickness piece of metal that is installed behind the blade, (call it whatever you'd like of course), is a manual solution to an automatic riving knife, for saws not otherwise equipped w/ a riving knife as standard equipment. In the case of the Unisaws, it includes a nicely milled bracket that attaches to the original, (and abandoned) guard mounting holes in the trunnion, and allows for the "manual riving knife" to be manually raised/ lowered as needed to remain below the blade for non-through cuts.

The guard itself is a very good blade guard, as far as those go, and allows for great overhead dust collection, and is easy to remove/ reinstall as needed w/o moving or removing the riving knife as they are 2 independent parts.

 

Keye

Keye
Corporate Member
MJ, or Micro Jig is just a splitter. No hold down. I used a feather board.
MicroJigs can be bought and configured for thin or wide, and can be adjusted for small offsets. I found it does not take much to keep the work from catching a tooth.

For my new saw, I attached a T-track so I can continue to use a feather board until I pay the big bucks for Jassem hold downs. As far as kick back pawls. I believe they are useless. The force of a real kickback will bent any of them into a pretzel. The idea is to not have a kickback in the first place.

Microjig gripper is a nice push block. That's all. It does not hold the wood down, you do. It is a bit small and puts you right over the blade. I don't like at all some of the uses they show. I won't be right over the blade pushing down no matter what!

A splitter is different from a riving knife. The big difference, and the one that drove me to buy a new saw, is the riving knife is about 1/4 inch behind the blade at all times. I had a small piece turn BETWEEN the blade and splitter. Second is that it is just below the blade, so you don't have to remove it for non-through cuts. You do remove it if you use a smaller blade as some do for precision or a dado. I guess one could make a knife that fits a small blade if that was your SOP setup. Or if using a splitter, make an insert with the splitter close to the smaller blade slot. When the wood wants to close up noting beats a wedge in the far open end. Wood can still bind on the splitter. Better than the blade, but still a problem. Some suggest a pin for a splitter to reduce the binding.

The over-arm unit as mentioned above may make a fine blade guard or dust collector, but has nothing to do with a splitter or knife. The above mentioned Delta splitter is just that, a splitter so it's distance to the blade is too large and it is only for through cuts. Better than nothing, and would have prevented the near miss I had on the Ridgid where thin stock went UNDER the splitter.
"Some suggest a pin for a splitter to reduce the binding." Scott, help me out on just what you mean.
 

Keye

Keye
Corporate Member
Am I correct thinking a splitter needs to be the same thickness as the blade and a riving knife does not. I know I am taking the lazy way by asking and not looking for the answer.

Scott, thanks for the definition explaining the difference between a splitter and a riving knife.
 

pop-pop

Man with many vises
User
The hinged jig has now scared the heck out of me, it is gone. I am thinking about using the BS to cut tapers, more sanding but not a big deal. Is this idea dumb.
What is an MJ?
A sled tapering jig has a huge advantage in that it is adaptable to safely hold stock for oddball cuts. Here I am cutting a stack of three pieces of aluminum for the vise workshop. The shaped plywood piece holding the red-dyed aluminum was all that I had to cobble up.

4AD7831A-1C62-4FC9-BE67-A161D5080058.jpeg
 

tvrgeek

Scott
User
To prevent kickback, both can be just a bit thinner. To prevent wood closing, I guess closer to blade thickness, but I measured mine, and they are a bit less than 1/8. Odd size really. But I use a wedge for closing wood anyway. The MJ splitter design gives you different thickness blades and different offsets so it can assist in holding right to the fence. I rely on a feather board.

As I have the old MJ parts from my old saw, I can use them to make a ZCI for a 7 1/4 blade if I ever decide to do really precise small work. I would know the depth of cut and could set the splitter right behind the blade exit.

Some DIY splitters instead of being a blade, are just a thin post sticking up. The function is to prevent the work from turning and catching a back tooth. You can do some GOOGLEING to see. Personally, I like the longer blade as the longer it is, the less angle the work can twist to for a thinner blade.

Shark does have a good rep for decent parts and good dust collection. A nice fold up splitter is an improvement and anyone with a Unisaw should get one, but it is not a riving knife.

My guard is designed to have a dust port on the top, but I have not found one close yet. I am sure it is off some other machine produced by the same few OEMs. At least it is the two independent side type so it will worker on thinner rips.
 

Hmerkle

Hank
Corporate Member
It is funny I have put a lot of wood through an OLD Craftsman contractor saw with a 1 HP motor.
Obviously a splitter nor riving knife were standard equipment back then...

I HAVE had wood do some WEIRD things as they go through the saw (kerf closing, warping, cupping, etc.) but (knock on wood) I have never had a kick-back motor stall due to the kerf closing...
Now the one upgrade I did to the saw was a "Largeish" "Panic" stop button at knee-level and the very second something bad starts to happen, I HAVE shut down the saw!

I know how fast things can go wrong with a blade traveling at thousands of surface feet per minute... and don't get me wrong, If I ever buy a new saw I would have one with a riving knife or splitter, but my point here is being respectful of the tool you are using, working safely and understand what can go wrong and what happens when it does.
 

junquecol

Bruce
User
A sled tapering jig has a huge advantage in that it is adaptable to safely hold stock for oddball cuts. Here I am cutting a stack of three pieces of aluminum for the vise workshop. The shaped plywood piece holding the red-dyed aluminum was all that I had to cobble up.

View attachment 200603
T-track system is the same as Jim Heavy's over at Wood Magazine. Rewatched his video last night
 

junquecol

Bruce
User
Sloppy miter bar? Sounds like a good way for a sloppy cut, burn or catch. No. Make it snug. Push the work/sled through clear of the blade.
By making it a little loose, you have to push work towards blade on forward stroke (no slop,) and away from blade on return stroke. This way blade doesn't contact the work piece on return stroke, causing it to be thrown forward on the saw. Idea was originally in FWW's build of taper sled. Can't remember the author's name
 

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