I am purchasing a dado set for the first time. I have heard that a lower hp saw, such as my Ridgid 1 1/2 hp, would do better with the 6″ dado blade rather than an 8″ dado. Can anyone tell me how deep a 6″ will cut vs an 8″. And should I stick with the 6″. T hanks for your comments.
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Replies
Either should cut 3/4" deep, do you need more?
The main problem with the smaller blades is number of teeth vs chip clearing. I also dont know of any good quality 6" sets, though Forrest probably makes one. I had a 1.5 horse contractors saw and used an 8" set with no problem. I could take a 5/8" x 5/8" or 3/4" x 3/8" in one pass. Although not in hard woods.
Mike.
I don't think the horsepower of your saw should determine whether you buy a 6" or 8" dado set. I think Mike (above post) is right that the real issue is the number of teeth.
What do you want to use the dado for?
Thanks to all your replies. I am building a book case and need to dado the inside sides for the shelf hardware standard. I could use my router, but I thought the dado would be the most accurate. From all your replies I believe the way to go is to buy the highest quality dado set to get the cleanest cuts. I looked at the Freud, and its high price. But I guess it's all relative, ie: quality vs cost. Also have heard some horror stories re: accidents using a dado blade with not guards in place. Is this something I should be concerned with, other than using good safety practices. I have a great deal of respect for the table saw, and am very conscious of potential hazards. Thanks again.
Another note about dados on a Contractors saw... My uncle, who's opinion I respect a lot, told me that it is a shame to put a nice blade (like forrest) on a contractors saw because when the blade is loaded it slows down causing it to heat up and wear the blade prematurely. His words were something to the effect of " A contractors saw bogs down too much and burns up blades". If you feed slow enough to not bog it down you'll start burning, even worse on the blade. A dado is definately going to slow down a lot more than a combo blade. I have no imperical data to back this up, but it all makes sense. contractors saws DO slow down in the cut and that DOES heat up blades and the instructions with the blades say that heat kills the edges. So I would not blow $300 bucks on a top of the line dado, get a good 80 to 100 dollar Freud set.
Have fun,
Mikeplease excuse my spelling.
In respect to your uncle, I will say he is wrong. Carbide does not wear any faster with higher heat until it gets to the point where the carbide binder deteriorates. That takes far more heat than you can generate with a saw blade no matter what wood you are cutting.
Howie.........
Howie,
The instructions with that came with both my Forrest and CMT blades say anytime you can smell wood burning it will shorten the life of the blade. That may just be CYA on their part though, I dont know. My uncle runs a large cabinet shop and buys blades and bits in bulk. He used to use high quality blades on site in contractors saws for trim work when he noticed that the blades were not lasting as long as the ones on the cabinet saws in the shop. Granted this is not a very scientific observation, there are many other variables compairing on site trim work to production cabinet work. But that was his summation. All in all I definately think dropping $100 on a combo blade is a good idea regaurdless of the saw, but $300 on a dado set.....
By the way one of the reasons people buy $300 dados is to get flat bottoms. My $130 set is pretty damn flat. Do yall think that it really matters that much. Any time I make a dado I am going to glue a board into it so the bottom it not visible, It really isn't going to add significant strength as it will be matched up to end grain. Is there some other advantage..tearout, feed rates, durability?
Thanks yall,
Mikeplease excuse my spelling.
>>By the way one of the reasons people buy $300 dados is to get flat bottoms. My $130 set is pretty damn flat. Do yall think that it really matters that much.
You can get flat bottomed dados for a lot less than $300. The $75 - $95 Frued SD20x dados give virtually perfect flat bottoms. But, I'm with you. There is much too much made of perfectly flat bottomed dados. More important IMO is a dado that crosscuts veneers cleanly without chipout. The bottom of a dado is never seen but the cutline is almost always visable.Howie.........
I use my dado set to make tenons; helps to be flat, in that case.
Charlie
I tell you, we are here to fart around, and don't let anybody tell you different. --K Vonnegut
Charlie,
good point.please excuse my spelling.
Hi.
I know I advocated the Forrest Dado set..it's good, but if ALL you're going to do is one or two dados, the router is an excellent tool and just as accurate with the right guide.
Good luck!
lp
As far as your safety concern, one thing: because a dado set takes a large mass of wood in one pass, go a little slower.
Other than that, it's no more or less safe than other ts operations.Remember, do not use the mitre guage and fence on the same cut.
Re: dado hazard
You're absolutely right to be cautious and extra careful when using a dado. Because of the width of the 2 blades (plus chippers), there is a vastly greater potential for serious kickback.
In cutting the grooves for your shelf standards, you would be well advised to mount a feather board on your fence. This will give you some help with the kickback problem, but it will also keep the board pressed flat against the saw table -- insuring a uniform depth of cut.
Also, it is true for any ripping operation, but while ripping dados you want to be sure to stand to the side of the board as it goes through the saw -- rather than directly behind the board.
As for the advice from Mike's uncle, I would also disagree. The higher quality the dado set, the better cut you'll get -- no matter what style of saw you are using.
Finally, if you are planning any cross-cut dados for your book case, I would suggest using your router -- safer, more accurate, and probably a better cut than you will get with any dado.
Good luck........
I frequently do the mortised shelf standards & use a 5/8 straight bit & a router with an edge guide, it goes really quick, plus it's cheaper to buy bits than sharpen dado sets, I think.
I have a Jet 1 1/2 HP contractors saw and purchaser the Freud 6" dado set on recomendation of the Freud rep at the wood workers show. I am in the process of building a new router table and have used this blade to cut numerous dado's int 3/4" 9 ply sheet goods. The blade has performed flawlesly and I would be hard pressed to bog it down. Unless yopu need to cut 2" deep grooves or dado's, you don't need any more than a 6" blade. Do the bearings in your saw a favor and stay away from the 8" size.
Hi.
I have a Jet Contractor's saw...pretty flimsy power-wise..compared to the 3-5 hp saws.... I spent big bucks on the Forrest Dado King..it's expensive but give the cleanest cuts possible and has NEVER bogged the saw down, even with the all of the blades/chippers attached...
It's an 8" model.
Just go slow, use good dust collection and be safe!
lp
Someone gave me a Craftsman dado set & I used it for a while, but I had problems with chipout & uneven bottoms. I bought the Freud SD508 and couldn't be happier. It makes flat bottomed, tearout free cuts in any kind of sheet goods. And since I bought it, I haven't made a tenon any other way. There can be some blowout on the trailing edge of solid stock due to it's negative rake angle, but that's easlily solved by using a backer. I have no problems using it with my 1.5hp Delta contractor saw. One of my best tool investments ever.
i use the same ridgid saw & use the 8 inch freud super dado, & it works great, take care...
I have an older 1.5HP Jet contractor's saw and use the Freud Safety Dado. It does an excellent job at a much more reasonable price than the Forrest and many other, lesser quality, dado sets. It's always been hard for me to imagine needing to dado any deeper than the 6" will go!
If I were buying a dado set today, I'd have a hard time passing up the Freud SD606, which is the 6" version of the Dial-a-Width stacked dado. It can be seen here.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Another proud member of the "I Rocked With ToolDoc Club" .... :>)
FG,
I took advantage of the link you provided and was chagrined to see negative tool reviews (for the 8" version) on the Amazon site that, most importantly, cited challenges with the dado set being too wide for the arbor.
Secondarily, they panned the cheap container, but I'd make one out of wood anyway, so that's not much of a concern for me.
Have any fellow "knotheads" experienced challenges getting the Freud dial-a width dado sets to fit on their saw arbor when set to full width?-Jazzdogg-
Whether you think you can, or you think you can't, you're right.
Here is how to figure the arbor length needed to utilize the full width of Freud's Dial-A-Width SD608 dado:
You need an arbor that is 7/32" (for the hub) + max width of dado (13/16") + nut (measure yours). Therefore, the Dial A Width needs 1 1/32" of arbor shaft length. Add to that figure the width of your arbor nut and you have your answer.Howie.........
Thanks for the heads-up, Howie!-Jazzdogg-
Whether you think you can, or you think you can't, you're right.
I would recommend a 6" dado for your contractors saw for a couple of reasons:
1. You'll probably never make a dado deeper than 1.5"
2. An 8" set weighs about 5.5# (CMT 8" set) and that is a lot of mass to be swinging.
3. a 6" set costs a lot less than an 8" set and who are trying to impress.
_________________________________
Michael in San Jose
"In all affairs it's a healthy thing now and then to hang a question mark on the things you have long taken for granted." Bertrand Russell
I have a 3hp cabinet saw and an 8" CMT dado set which is very nice and has the capacity I need most off the time. There's been a few times I could have used an even bigger set. I use the two outside blades with spacers to cut both cheeks on tenons in one pass and could have used more blade. My gut feel is that the bigger diameter blade will do a better job even on a lowered power saw. Especially so if you get a good set with 4 blade chippers. I haven't used the Freaud adjustable but I've never used a wobbler that left a clean enough bottom to show and in between the outside blades the Freud is just a wobbler. Get a good set and you'll never have to buy another one. BTW I "settled" for the CMT because I needed it "now", my first choice at the time would have been Systematic.
John O'Connell - JKO Handcrafted Woodworking
The more things change ...
We trained hard, but it seemed that every time we were beginning to form up into teams, we would be reorganized. I was to learn later in life that we tend to meet any new situation by reorganizing; and a wonderful method it can be for creating the illusion of progress while producing confusion, inefficiency, and demoralization.
Petronious Arbiter, 210 BC
John,
If you are only using the outside cutters from the dado set for cutting both sides of a tenon at once, why not use a matched pair of combination or rip blades 10 inches in diameter, that would give you an extra inch of depth compared to an 8 inch dado set and a pair of rip blades would, most likely, cost less.
Second, to correct a common misperception, the Freud Dial-A-Width dado set isn't a wobbler type. The set still comes with five chippers, the dial only controls the final 1/16" of adjustment eliminating the hassle of using shims. The dial moves the blade horizontally on the shaft, it doesn't tip the blade over to change the width of the cut.
John W.
I have considered using the two 10 blades and probably will go that route when the need arrises again. Thanks for the clarification on the adjustible dado too.John O'Connell - JKO Handcrafted Woodworking
The more things change ...
We trained hard, but it seemed that every time we were beginning to form up into teams, we would be reorganized. I was to learn later in life that we tend to meet any new situation by reorganizing; and a wonderful method it can be for creating the illusion of progress while producing confusion, inefficiency, and demoralization.
Petronious Arbiter, 210 BC
By now, this subject has been beaten to death, and we lost the originator several days ago, as the replies go "unread". But I would be remiss not to suggest that smoothness of cut may be related to cutting speed .... not only feed rate of material past the blade, but the tip speed of the teeth doing the cutting. At the fixed speed (3600 rpm) of most affordable table saws, the smaller the diameter of the blade, the lower the tip speed: a tooth on a 6" is running 5600 fpm, an 8" is at 7500 fpm, and a 10" is at 9400 fpm. With combination ground flat (sided) blade sets, your 6" blade might have 30 teeth, the 8" might have 40 teeth and the 10 " might have 50 teeth, which translates to 1800, 2400, & 3000 cuts per second respectively.
For those with slightly underpowered saws, the larger set will have more mass and thus more momentum, translating to less bogging down during the cut. This usually means smoother running, vibration free, no-chatter cuts.
The good high carbon steel blades can be ganged on the arbor (backwards, of course), jointed and refiled to give you the smooth, flat bottomed cut you might desire. Just be sure to do ALL the chippers, every time.
That said .... my 10" Walker-Turner tablesaw has only seen a 1950's vintage, high-carbon Simonds 8" flat ground set with combination grind on outside blades and two tooth chippers. Back then, I couldn't afford the 10" set, so settled for the 8". At that diameter, they are a lot easier to load on the arbor, and juggle the shim thickness than the full 10" dia. set would be. Never needed more than 1" depth of cut, but the 1 1 1/4 total width has been handy for tenon work.
Thanks for your ear (eyes?)
John .... now elated to be back in TEXAS!
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