Is this safe?

[Brian Brown]

I am making some breadboards for Christmas, and I want to put some short feet on them like shown in the drawing. The only accident I have had in the shop that was more serious than a staple through the finger, happened using a stacked dado set. I nearly lost a finger. I never figured out what caused the accident, so I am now extra careful with a dado set. My question is, is it safe to cut a dado with the blade set at an angle, leaving a dado like the one shown in the pictures. There is a nagging in the back of my brain that says not to, but it may just be the hamburger finger from years past talking. Thanks for the help, and sorry for the lousy drawings.

[Rick Fisher]

Hey Brian .. Great question..

I have never done it but would bet your at greater risk for a kickback.. if the board lifts, it wont lift at the angle your cutting .. I would want to ensure there was a featherboard holding the piece down as well as against the fence ..

I would probably do it with a router .. pin a strip of 1/4" stock to one side, run the router on an angle... I dunno .. I would think it through as to what can go wrong ..

Hmm.. Even my router idea gives me pause .. need an edge guide .. Do you have a radial arm saw ??

[Carl Beckett]

These dont look deep. As Rick points out, if it lifts its gonna grap the edges.

Im not convinced a router would be any safer.

Given the relatively shallow cut, I would likely do it but with a good setup to hold the board both against the fence, but down flat on the table (its a straight through cut so this is good). Make sure the piece is flat and doesnt have any rocking - rocking part way through would also cause it to grab.

At the same time, if its making you nervous... there is a reason. Your gut has these instincts due to evolution....

[Matt Day]

If you're worried about the board lifting and kicking back, here's two ideas that came to my mind:
1. Take a series of shallow cuts with the dado blade.
2. Cut the edges of each dado with a normal kerf blade, and hog out the middle with a dado

[Stephen Cherry]

Brian, I'll defer to others whether it is safe or not to angle the dado blade, I just do not know. That said, how hard would it be to put together a angled jig that rides in the miter slot, and attaches the workpiece with 4 destaco clamps? A couple of wedges of the right angle, a piece of miter bar, a top plywood surface, and the clamps. I've got a bunch of clamps, plywood, screws that I keep because for me it always feels more secure to put together a jig than to worry. Particularly on the shaper.

Also, this is another case where the sliding table saw would, with a good clamp would put you almost there in making the cut, and also would keep your hands somewhere in the next county if something goes wrong.

[Rian de Bruyn]

I made the same thing but on a RAS !!!
I made a jik to cut that with a single blade and multiple passes because i do not have a dado blade
BUT i think you will be able to use a TS with single blade aswell

[Jay Jolliffe]

I made a sled to due dadoes for my table saw & I don't see a problem using it for that as I already have. Just hold it flat to the table or sled.

[glenn bradley]

Rule of thumb; if you don't think its safe, its not. I do angled dados without incident. Kickback comes from a bad feed path or a lack of stock control. A dado is hogging out more material per pass and so the "resistance" to the feed is greater; more chance of material control issues. Generally if it takes more than a mild effort to feed the stock through the cutter, something is wrong. Dull cutters, friction on the tables/fence, poorly prepared material (not jointed flat), alignment or something else that should be fixed before proceeding. I'll stop and re-align the saw before I'll offer up a digit ;-) In the end it doesn't matter what other people do. If in your shop, on your gear, with your hands, it doesn't feel safe; don't do it.

[Sam Murdoch]

In my experience one of the risky aspects of using a table saw - with or without the dado - is passing a small nearly square board over the blade. By small I mean only about 10" to 12" or less. The chance of pushing such a piece, with so little surface bearing against the fence, slightly askew is great and would result in blade grab and throw or worse.

Having said that - I think your intended operation is safe but in order to provide as much bearing and hand hold I would run as long stock as I could - say 3 or 4 cutting boards worth before croscutting. Also use finger boards.

Good for you to trust your inner voice and ask before the operation. As Glenn writes "if you don't think its safe, its not".

[Mel Fulks]

Done that many times. One danger is a little pitch ,rust, glue or other debris on the table or fence. Clean and lube and your work won't hang and twist and kick back. Smooth feed makes it pretty safe, but to can also push with a block with sandpaper glued on,etc., as safeguard.

[jeffrey bailey]

I have made dado cuts like that when making cradles. Never had a problem with them.

[Tom Esh]

I've done it many times and I've never felt it was much different than a 90 deg cut safety-wise. However I use grip-faced push blocks to feed dado cuts, not only for safety but to keep long pieces flat and prevent lifting. If the piece lifts on a straight dado, no big deal - just run it through again to get the full depth. However if it lifts with an angled cut, you end up with a dado that's not only too shallow, but too wide, which can't be fixed so easily. I don't see lifting as being an issue for what you're doing, but I'd still use push blocks.

[Rich Engelhardt]

My question is, is it safe to cut a dado with the blade set at an angleMake the dado flat. Angle the legs.
Unless I'm looking at it wrong?

[Brian Brown]

The board lifting during the cut is definitely the problem I worry about. I have had it happen with a single kerf blade, and watched the wood go whizzing past me. I don't have a RAS, and my router table doesn't tilt. I thought about using my hand held router with a jig to angle the whole set up, but I only have a 1/4' shank, and that requires the bit to be chucked shallower than is safe, and puts too much force on that tiny shank. That scares me worse than the dado set. Using a single kerf blade with multiple parallel cuts won't leave me with the bottom of the dado angled, but I can just cut the corresponding angle on the mating surface of my foot. Also, it will leave me with a repetitive chevron pattern surface that will take a lot of work with a chisel to clean up. I think will set this up on my TS with the stacked dado set, with a feather board on top, and on the side, and make several shallow passes, Fortunately my dado set is sharp.

Thanks for the help, and alternate suggestions. If anybody has others, I won't be doing this until Saturday, so all ideas are welcome.

[Prashun Patel]

I think this can be made 'safer' by designing a good push jig or sled for this. As long as you are able to move that board straight, it should work.

Also double check your throat plate for level with the saw top.

Last, while it means more passes over the blade, I prefer to do dados in multiple shallow passes. Less force to contend with = easier to move thru with confidence.

[Mike Cutler]

Brian

It can be done safely, but a little forethought may be required.
It definitely requires a ZCI specific for the task, and a good one because there is going to be a good amount of pressure to hold the work piece down, so you don't want the ZCI to flex on the trailing end/edge of the cut. Even a light cut, with a slight angle, the dado stack will want to move it away from the cut in the angle it's being cut.
It should be done in one pass, because multiple passes make the edges ratty,and can lead to inconsistencies in the final depth of both sides.
Make a good "push block" to cover the entire area of the piece where it will make contact with the blade. You want to be able to think about applying downward pressure without thinking about that dado stack. Nothing different than a normal dado. You're not really cutting that deep into the workpiece, just enough to establish the reference angle, so the dado won't have a full load across it. Meaning that while the blades contact across the face, the amount of material being cleared will be less on one side due to the angle.
I think you can do it safely, but if you don't think so, don't do it.

[Greg Portland]

Make the dado flat. Angle the legs.
Unless I'm looking at it wrong?
+1. IMO it will keep the top stronger which is important with a cutting board.

[Rod Sheridan]

I've made angled grooves many times with the tablesaw, however I always use a stock feeder for it.

2 Reasons;

- if it moves you will have a kickback

- the stock feeder acts as the cutter guard

Regards, Rod.

[Lee Schierer]

Brian, I'll defer to others whether it is safe or not to angle the dado blade, I just do not know. That said, how hard would it be to put together a angled jig that rides in the miter slot, and attaches the workpiece with 4 destaco clamps? A couple of wedges of the right angle, a piece of miter bar, a top plywood surface, and the clamps. I've got a bunch of clamps, plywood, screws that I keep because for me it always feels more secure to put together a jig than to worry. Particularly on the shaper.

Also, this is another case where the sliding table saw would, with a good clamp would put you almost there in making the cut, and also would keep your hands somewhere in the next county if something goes wrong.


Doesn't this still put the dado blade at an angle to the cut just as it would be if you tilted the blade. You would still need to hold it down and tight to the bottom of the jig. Since the blade is going to have to be raised up higher out of the TS I would assume using a sled with and angled surface would be more dangerous.


Brian,
Tilt your dado blade to the desired angle, lower it all the way down. Put in a new zero clearance insert, turn on the saw and slowly raise the dado through the insert to the desired height. Place your stock on the table. use a feather board or several to hold it tight to the fence. Use push blocks to hold the stock down while pushing it through the cut. If you are concerned add additional hold down feather boards or a hold down board on the fence. You can also take several shallow cuts to reduce the chance of kick back. Just don't get the set up so tight it is difficult to push the board through the cut.

[Stephen Cherry]

Doesn't this still put the dado blade at an angle to the cut just as it would be if you tilted the blade. You would still need to hold it down and tight to the bottom of the jig. Since the blade is going to have to be raised up higher out of the TS I would assume using a sled with and angled surface would be more dangerous.


.

It seems like the sled in the slot would eliminate the possibility of twisting, and having the blade verticle would reduce the tendancy of the blade to grab if the wood does go up slightly. In my estimation, a wedge shaped sled, in the slot, with a lip at the back end and 4 clamps would make this just another cut. You could even rig up a over blade gaurd from the rip fence.

[Sam Murdoch]

This would be so safe & easy with the Festool Domino :rolleyes:! Of course it wouldn't be the same joint but it would be rugged and clean.

[Mike Cutler]

Make the dado flat. Angle the legs.
Unless I'm looking at it wrong?

You'll have to put a shoulder on the legs if you do it this way. The hypotonuse of the angle will increase the width.
It's still a pretty easy solution.

[Steven Hsieh]

To me it looks fine.

If you are worry allot, I would do it in 2 pass.
And do a TEST PIECE FIRST!!



Use 2 Bench Dog push stick and push it against the fench

244003

[Mark W Pugh]

Make the dado flat. Angle the legs.
Unless I'm looking at it wrong?

How would the angled leg fit in to the straight dado? Or use something like this. http://microjig.com/products/grr-ripper/index.shtml

[Gary Herrmann]

The little man in the base of my brain flinched.

What about:
1. Marking out the angle on the side of the cutting board
2. Transferring that angle to a wedge shaped board
3. Taping/hot glueing the boards together
4. Raising the stack enough to get the angled cut into the bottom of your cutting board and then repeating?

That, or a handsaw, and a wedge shaped wooden sole mounted to a router plane.

[Rich Engelhardt]

You'll have to put a shoulder on the legs if you do it this way. The hypotonuse of the angle will increase the width.


How would the angled leg fit in to the straight dado?
I'd cut one side of the dado to match the angle & make it a sort of weird half dovetail looking joint.
As Greg mentioned, that would leave more "meat" in the cutting board.

[Lee Schierer]

It seems like the sled in the slot would eliminate the possibility of twisting, and having the blade verticle would reduce the tendancy of the blade to grab if the wood does go up slightly. In my estimation, a wedge shaped sled, in the slot, with a lip at the back end and 4 clamps would make this just another cut. You could even rig up a over blade gaurd from the rip fence.

Ah, yes, but it appears that the desired angle is quite small, in the range of 10-15 degrees. How is this sled going to get cut to that small angle? If this piece is not wide enough for a rip style cut (wide enough to put proper support against the fence so it doesn't rotate), then a sled is probably the only safe option.

[Jay Jolliffe]

Your making this too complicated. If you make the cutting boards flat with no warp & sits flat against the table on you saw you should have no problem cutting this with a sled or against the fence & a dado blade. Just do it in a few cut's....

[Carl Beckett]

Your making this too complicated.

Im not so sure 'he' is making it too complicated, or 'we' are......

But that is one of the great things about this site - so many different approaches and philosophies.

[Jay Jolliffe]

I guess your right Carl....Sometimes to much thought is put into something & everyone has a different thought......kick back is scary. I had a piece travel 25' & put a silver dollar size dent in my freezer....I guess you can never be too careful so I apologize for my first answer.....

[Carl Beckett]

I was jesting Jay... not meant to be critical in any way (no apologies needed). A lot of truth is said in jest though.

But ya - I have a thumb that clicks from a kickback/ER incident. I still have the thumb though, so this is good. My opinion was that I would do that cut. But again - I have a thumb that clicks so what does that say about my judgment? ;)

Each of us has to take responsibility for our own safety. Many times I have gotten great advice here, which has made me rethink something. Safety and health (for me at least), is something where if we 'police each other' - can help us slow down and consider it more carefully. You never know about the accidents you avoided.

[Brian Kincaid]

I think there are two good options:
1) Miter slot sled with workpiece clamp-down
2) 2nd fence on opposite side of blade (like you would use for a cove cut)

-Brian

[Erik Christensen]

how about a router sled - I would use a guide bushing and size the slot so that with the bit diameter & guide busing you got a dado width equal to your stock for the legs. then you just shim one side of the router sled to give you whatever angle you want... don't need a big router or bit - it just takes more passes. might take a bit more effort than other solutions but seems the safest apporach

[Brian Brown]

Well, it's finished. See this thread for the Report. http://www.sawmillcreek.org/showthread.php?193660-Angled-dado-cutting-success-and-still-have-10-fingers