In preparation for using my new dado stack for the first time I was catching up on safety, tips & techniques and found this on a video. On an otherwise knowledgeable and informed YouTube channel a person was demonstrating dado stacks and the host cut a dado on a piece that was wider than it was long without a miter gauge and against the fence.

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This is in direct opposition to everything I have ever been taught about table saw safety, that being that a piece like this should be supported by a miter gauge (or miter sled) and should not be trapped against the fence incase it twisted and kicked back.

What are the stability & safety rules for cutting dados on a piece like this? Are they different using a dado stack than a saw blade? I would think that, because of their gripping surface, a dado stack could be more dangerous with regards to kickback than a single blade. Is this different with a milling action rather than a cutting action?

Even if he was using a router bit on a router table it would be my understanding that it would be advisable to place additional stock behind that piece to stabilize it against the fence.

Survey says...?

Thanks!

For someone that is a beginner it would be better to use a mitergauge. All that is important is the board stay against the fence and a miter gauge would help do that. A person that is experienced is likely to run a dado like that without a miter gauge or a push block like that. Personally I think that type push block is extremely dangerous. If the wood and the push block isn't cleaned every time dust can cause it to slip. I got some free with a machine onetime and threw them in the trash before the day was over.

 

Personally I think that type push block is extremely dangerous.

It's hard to tell from the blurry photo, but I think that push block has a lip on the rear to catch the edge of the piece so it won't slip off.
Other types rely solely on friction and may slip if not cleaned as you suggest.

 

This is in direct opposition to everything I have ever been taught about table saw safety, that being that a piece like this should be supported by a miter gauge (or miter sled) and should not be trapped against the fence incase it twisted and kicked back.

Your statement is confusing to me, sorry.
Two things are different when cutting a dado as described.
First, it's not a through cut like a saw blade may be, creating a loose off cut, which if it binds, it may kickback.
The dado is still all one piece of stock, so, no loose pieces wandering around.
Second, if the width of the piece is sufficient to have a secure registration against the fence it will be safe.
But, by supporting and pushing the piece with the miter gauge, it will not twist and bind like doing it "freehand".
It will have more controls in place, so safer. I've done it may times.

 

As Steve mentioned you need a miter gauge (At least). You can still use the fence. Which table saw do you have?

 

Survey says...?

Thanks!

You are correct in your criticism. It’s a horribly unsafe way to do the cut. And one more example of how YouTube can be risky.

General rule of thumb is if ply width is less than 1/3 the length you should not use the fence. You are essentially making a crosscut and should use a miter gauge or sled. I have to disagree a shoe with a heel may be a little safer, but not much, it’s just plain wrong.

Re this specific cut, the same principle applies. Fact is, a dado is far more dangerous cut b/c it is a) not a through cut and b) a dado blade has a lot more mass behind it. If there is the slighted bobble or misdirection the blade will grab, the board will kick back, and if it grabs the shoe, it can be tipped up and your hand is pulled into the blade. I’ve had something like this happen to me (no injury) and like all incidents it’s over in like 1 millisecond and your in shock.

I have a SawStop now - insurance for when my 67 year old brain isn’t firing on all 8. 😁

 

When I was learning woodworking I was taught to never have the stock against both a miter gauge and the fence at the same time. More so for doing cuts than a dado. We would clamp a block on the fence to register the location of the cut. As the stock moves past the block it is no longer in contact with the block or fence. Today I would have a straight stock on my miter gauge (in my case I use an Incra) and have a stop on that to register blade distance. The slightest binding in two direction, the fence and miter, is not a good recipe. I still follow what I was taught 45 years ago.

 

Stumpy says you can use both, a lot is explained here and well worth watching.

 

I can understand not cutting wood off against a fence using a miter gauge but this topic is about dado work.

 

I don't have a problem with the friction push blocks. They give more friction than my hands and you can keep them clean.

The photo shows the microjig grrr rip though, its different.

 

I have a grippy push (handle thing?) I use quite a bit, but more often than not I forget it and spit on my hands for a better grip although spit sometimes may leave less than desirable result in the finish from time to time.. Kind of depends on the piece.

 

here are some youtube vids specific on dado work from Stumpy Nubs.

https://www.youtube.com/results?search_query=stumpy+nubs+dados

Dado cuts can be very dangerous simply because the set takes an aggressive cut in the stock. The key is solidly controlling the work piece across the saw. I am not a fan of the miter ga and fence working together ever.
If you are unsure get off the saw and go to a good router bit. You can capture the router base between to carefully arranged straight edges and take a much safer cut. BTW a good straight edge also will work great with your circular saw work.
Just some ideas here aluminum straight edge for router - Google Search

calabrese55

 

The key is solidly controlling the work piece across the saw. I am not a fan of the miter ga and fence working together ever.

We will disagree on this subject, but I think your statement is self-contradictory?
The miter gauge (occasionally with an extended fence like mine are ) is used to control and push the piece forward parallel to the fence and the blade.
The fence is set for a dimension from the end for accuracy and as a constant guide.
The workpiece can't move, shift or kickback if pressed down, forward and into the fence.
I'm not going to say you should try it, but I have done this many times, safely.
It's not unlike just using the fence by itself, but you really need to firmly press in all three axis for that!
Any variation will cause a kickback. But at least the blades are low, buried in the material and won't result in a flesh eating incident!

 

I would say I have more experience with dados on a table saw. If it’s working and you feel no need to adjust, just keep doing it.

The best experience, is practice …He careful..

 

Using a table saw safely is all about two things:
A. Understanding the physics of high speed rotary cutters of large diameters.
B. Keeping your fingers and hands far enough away from the cutters to prevent injury

For example, if you take a saw blade of 10" diameter and spin it at 3500 RPM and engage a piece of 3/4" thick wood into it on the table saw here's what can happen. If you don't control the workpiece so it is running parallel to the "plane" of the blade, it will bind. and kickback. The amount of the blade that's into the wood, about 8" or so, will resist any change in direction and bind in the kerf, resulting in a kick back.

A router bit has much less area contacting the material, more like a line than a plane, geometrically speaking.
So, the danger of a kickback is far less. You can round over or profile a curves edge easily , and that's a primary function of a router.
The kickback danger of a router is from feed to with with the rotational direction of the cutter.
The cutter wants to "grab" the work rather than cut it and take it with in the same direction.

A dado set make a wide path into the material and if set too high, it will be a very aggressive cut.
The safety "advantage" of using a dado set it that the cutters are below the surface of the material during the operation.
So, the chances of getting cut are much less. The chances of a kickback are about the same as the table saw, however.
I can't ever recall having a kickback making a dado. But any time the workpiece moves away from the end of the fence, a kick back is most likely to occur. I had them on the table saw a few times, and then I reinstalled my splitters which prevent that movement and never had one since.

You can keep your fingers and hands away from the blade by following the standard table saw safety rules.
Use pusher shoes or blocks rather than push sticks because they allow more downward pressure.
When you hand gets within the red zone of the throat plate apply the pushing and pressing forces with a push block or shoe, not you fingers.
When the piece being ripped is very narrow, make a thin push shoe from a 1/4" piece of plywood.

Stay safe.

 

You might just want to add a router to a table saw and use it for dados. I do…

#1… easier
#2 . Cheaper in the long run..
#3 many sizes available,
#4.. Safer

 

Why do you all keep talking about push blocks? They aren’t going to help the type of situation the OP describes!

But since you are, I make my own out of 2x4 stock and also use foam grout trowels. No way I see anything worth that money.

 

Yes, I make my own also.
For "friction" types:
I've used the grouter's with nice handles, with sandpaper and sticky taped to the bottoms. They are great!
I've used barn door handles screwed to a 3/4" block, 36 0r 60 grit sandpaper on the bottom.
There are sanding blocks from ptreeusa? that accept a 3" wide sandpaper tucked under the flap on either end.
I own 2 "Grippers", never used and a single off brand, which I prefer it's simplicity, also never used.

For the "shoe" types:
For the jointer, I use a 3" or 4" wide board about 16" long, with a 1/4" dropped "catcher" foot on the rear, dadoed in from a 3/4" square piece.
The handles for those and my table saw push shoes are "shop made" from 3/4" plywood with rounded edges and look like this:

These are popular, BUT do not offer the more stable control that the shoe handles above provide.
Your wrist can "flex" to the right or left more easily than when your fore finger is pointed down the slope on the shoe types. Trust me on this or try it yourself.
I've also purchased every pusher device I could find on Amazon and have a 5 gal bucket full of them under my saws.
Some work OK, others, I would never use. The orange and blue plastic ones are OK.
The orange painted wood ones I made. The thin one is for this rips close to the blade and between the fence, It will push and hold down at the same time!

 

What are the stability & safety rules for cutting dados on a piece like this? Are they different using a dado stack than a saw blade? I would think that, because of their gripping surface, a dado stack could be more dangerous with regards to kickback than a single blade. Is this different with a milling action rather than a cutting action?

This is the OP's question. There a push "block" photo in the OP's first post.
So any safety concerns, methods or means are relevant.
I've seen too many You Tubers using both hands to hold the skinny push sticks that offer little if any down pressure at the middle of the workpiece, and that folks, is very important!
A push "shoe" does provide that downward as well as forward feeding force and if you cant it towards the fence, it will do all 3, and that folks is very important!

Why do you all keep talking about push blocks?
They aren’t going to help the type of situation the OP describes!
But since you are, I make my own out of 2x4 stock and also use foam grout trowels. No way I see anything worth that money.

Yes, not needed if using a miter gauge to push the workpiece.

 

The question isn’t about push blocks, WNT, it‘s whether its safe to dado or cut a long board using the fence. You don’t do a cut like that, period. Push blocks are irrelevant.

Would you argue how long the handle should be on a 2# mallet to drive a finishing nail?😁.

 

I did NOT raise the issue of a push block!
It was Steve Neul who mentioned it.
I am responding to that.

Personally I think that type push block is extremely dangerous. If the wood and the push block isn't cleaned every time dust can cause it to slip. I got some free with a machine onetime and threw them in the trash before the day was over.

 

On an otherwise knowledgeable and informed YouTube channel a person was demonstrating dado stacks and the host cut a dado on a piece that was wider than it was long without a miter gauge and against the fence.

The OP's photo shows a piece that''s "longer than it is wide" ! And using a push block:

This is in direct opposition to everything I have ever been taught about table saw safety, that being that a piece like this should be supported by a miter gauge (or miter sled) and should not be trapped against the fence incase it twisted and kicked back.

This is how we got off into whether using a miter gauge and the fence at the same time would be advisable?
I stated that for a dado like shown ,It would be fine and infact, offered more control.
Others do not agree. We will agree to disagree.
If more control is safer, which I believe, I rest my case.

 

This is how we got off into whether using a miter gauge and the fence at the same time would be advisable?
I stated that for a dado like shown ,It would be fine and infact, offered more control.
Others do not agree. We will agree to disagree.
If more control is safer, which I believe, I rest my case.

I agree - so long as the TS fence and miter gauge fence are exactly 90°. 😁

Steve doesn’t read posts, but I’ll say it anyway - I’m guilty as charged for making cuts like that in the past - even crosscuts - and I got away with it. Even though most saw have a riving knife, doesn’t make it right, and irresponsible to condone for a newbie - 😳😳. Dados and grooves with a blade are probably more dangerous than rip cuts. The average guy with a Jobsite saw will more likely stall the motor than get a kick back.

Then again, a couple weeks ago I drove around Utah @ 90 MPH with my seatbelt clipped behind my seat for a week. SWMBO quit mentioning it. Oops I went off topic, we shouldn’t do that WNT 🤣🤣

 

Back 45 years ago I worked for a company that made a vanity basin which the top protruded forward of the cabinet. We made that part out of plywood 7 1/2" wide and however long the cabinet was, sometimes 8'. All of the cabinet construction was done where the sides fit in dados so I had to run countless dado's like that on the ends of those boards. I don't remember ever having one kick back.

 

bantering about the methods is always going to happen. I was in the tee shirt business for many years. There were idiots like me who printed for small customers spending for orders from $150 to maybe $1800.
The big guys were printing orders where the shirts cost the printer over $5000.00 and more.
The point is we all constantly beat each other up on our process and methods. At the end of the day we all were doing the same thing to a tee shirt but we all did it in different ways. The only difference was nobody ever really got hurt putting ink on a shirt.
Safety is important but should not be a topic of ire between woodworkers and our methods will always come into question.
calabrese55

 

I worked for Tennessee River dye house which was TJays competition. These companies were in Alabama till they moved. I also work for a t shirt print shop in Blue Springs, Missouri for awhile till I went back to cabinet making when I moved here.

 

A kickback using dados will happen before you know what happened.

As mentioned several times, You not always watching the cut at the dado, your watching everything.

If you want to use the fence, miter guage, push stick, etc, it’s all good just be safe..

 

Specifically to the OP's comment. "This is in direct opposition to everything I have ever been taught about table saw safety, that being that a piece like this should be supported by a miter gauge (or miter sled) and should not be trapped against the fence incase it twisted and kicked back".

The pic on the OP shows a dado cut on a piece of what looks to be nice piece of high quality 3/4" plywood. I do not believe that kickback - due to release of tension in the grain - would occur in this particular TS operation. Operator error during feeding is a possibility but would be likely attributable to poor technique, and that probability would increase as the length of wood increases. In the OP's pic length of wood is unavailable to us requiring us to speculate: it could be 18" or it could be 18'.

Assuming the TS's fence is correctly aligned, the push block is familiar and worked well, the dado set is of good quality and sharp, and the TS has sufficient horsepower to drive the dado set at 3/8" depth, I would feel comfortable making the 3/8" depth dado cut as shown in the pic if the wood was under a couple feet in length. I'd feel less comfortable as the length of wood increased ... until my discomfort would require me to set up the cut in a different manner. The OP's pic is not my preferred setup as I'd need to focus more carefully on technique and keeping the wood from shifting off its axis, but I could make the cut safely and accurately.


PS: I don't think I've ever had a dado cut on the TS bind and kickback. I'm not aware of how common it is. Have people had this occur? (I'm speaking of straightforward dado cuts, not exotic ill advised operations like lowering the workplace from above down onto a moving dado stack). Plywood I think is very unlikely for this to happen, but perhaps the right wood species, the right grain structure, the right combo of blade condition, depth of cut, misaligned TS, technique, could result in kickback?

 

I don't think I've ever had a dado cut on the TS bind and kickback. I'm not aware of how common it is. Have people had this occur?

My reponse to that is you are either extremely talented, very lucky or haven’t been doing this long. I have it happen one time and it wasn’t even a risky cut like shown. Dado blades are far worse than normal blades. They can maim you horribly.

A good rule to follow is if the length is more than 3x the width, use a miter gauge or router.

The key is take the time to think about the cut before you turn the saw on.

 

A majority of kickbacks are NOT blade pinches. Those typically result in a stall of the motor because the operator is ripping the piece and will still have enough leverage on it.

Kickbacks typically result when the wood moves away from the fence at the rear and the blade grabs it up and over the top and throws it back at the operator.

A dado will not typically result in that, but it's not impossible. The operator's "primary" responsibility when feeding the wood, is to maintain constant contact with the fence all during the pass through the entire cut. This is in addition to the downward pressure and forward feeding pressure.

 

A majority of kickbacks are NOT blade pinches. Those typically result in a stall of the motor because the operator is ripping the piece and will still have enough leverage on it.

Agree but not true with a shallow dado cut. I know, I’ve had it happen to me. If the blade gets out of thr groove bad things can happen, that’s why the OP’s example is so dangerous,

 

Here in the UK, Dado stacks are illegal.
johnep

 

Never use the miter and fence at the same time, ever. I learned this in HS after watching a kid cut his thumb off, I was right behind him waiting my turn. After opening my shop thought about it daily.
I made a small block of 1" wood that slipped over the fence. 1" so I could use the saw guage easier. For a dato cut I would use this. I would also attach a piece of wood to my fence for cutting rabits.
I've used the technique in the pictures when ripping. And have used it for a rabit but no datos that could bind. I was fortunate to have enough room for a dedicated TS for stack datos and one for everything else. Deltas
I have also received a nice 10" purple bruise on my gut ripping. Table saws are dangerous and accidents happen. You'll have that. Is the picture show bad technique ? Possibly but there are times you need to get the things done and hopefully you are familiar with and confident in your skills
Hey You'll have that man

 

Never use the miter and fence at the same time, ever. I learned this in HS after watching a kid cut his thumb off, I was right behind him waiting my turn. After opening my shop thought about it daily.
I made a small block of 1" wood that slipped over the fence. 1" so I could use the saw guage easier. For a dato cut I would use this. I would also attach a piece of wood to my fence for cutting rabits.
I've used the technique in the pictures when ripping. And have used it for a rabit but no datos that could bind. I was fortunate to have enough room for a dedicated TS for stack datos and one for everything else. Deltas
I have also received a nice 10" purple bruise on my gut ripping. Table saws are dangerous and accidents happen. You'll have that. Is the picture show bad technique ? Possibly but there are times you need to get the things done and hopefully you are familiar with and confident in your skills
Hey You'll have that man

You can use the miter and the fence with a saw depending on what you are doing. This is common on adjustable fences..

 

If you have been following this thread from the beginning you then you likely watched the video I linked to in post #12, if you came in later please go back and watch it, Stumpy gives a great explanation on what you can or can't do on a table saw, it will be six minutes well spent.

 

I don’t know what he shows on his videos. Never watch them..

 

Discussion starter · #1 · Jun 8, 2023

In preparation for using my new dado stack for the first time I was catching up on safety, tips & techniques and found this on a video. On an otherwise knowledgeable and informed YouTube channel a person was demonstrating dado stacks and the host cut a dado on a piece that was wider than it was long without a miter gauge and against the fence.

This is in direct opposition to everything I have ever been taught about table saw safety, that being that a piece like this should be supported by a miter gauge (or miter sled) and should not be trapped against the fence incase it twisted and kicked back

That rule that "the piece should be wider than long" is great advice.
What is important is to keep the edge against the fence no matter the length or width.
Any deviation will result in a kickback!
Through cuts, where the blade comes up above the surface, are different than shallow depth cuts like dados.
We don't want short, loose, narrow pieces between the blade and fence, unless guided completely past the blade.

A miter gauge, in combination with the fence, can be used on a shallow depth cut, like a dado, because there are no loose pieces.
A properly fitted miter gauge will have an extended fence:

This extension, safely pushes the pieces past the end of the blade and provide additional support against twisting during the cut.
All my miter gauges have an extended fence;

I made this an an experiment to see how well two gauges would move in widely spaced miter slots and it work just fine.
Notice the splitters on the the two saws which prevent kickback by maintaining work contact against the fence.
They must be removed for partial depth, not through cuts, however: