Table saw dado blade question

[Tom Porter]

I have a Ridgid contractor saw (TS3650) and want to try a dado set I inherited with my dad’s radial arm saw. When I went to install it with two blades and four chippers (for a 3/4 dado), I found that the arbor wasn’t long enough to use both blade washers. There wasn’t enough thread outside the washer to attach the nut. I can leave the washer off and tighten the nut directly up against the blade but I’m not sure if this is safe.

At 1 1/2 hp, I realize this isn’t a powerful saw and I’ll have to be conservative with the width and depth of dados I cut but I’d like to use the set if possible and 3/4” seems like a useful width.

Any thoughts?

[Steve Wurster]

I had a TS3650 for nearly 10 years and ran it with an 8" Oshlun dado set. When you get close to that 3/4" width you will indeed have to use just the nut without the washer. As long as everything is stacked in there correctly (i.e. no teeth are touching) and the nut is on tight, you will be fine.

[Frank Pratt]

Most arbors, even on cabinet saws aren't long enough for both washers when using the dado's full width. I manual for my saw says to leave off the outer washer if needed.

[andy bessette]

That saw is not up to the job.

[Steve Wurster]

That saw is not up to the job.

I beg to differ on that one. As I noted, I ran an 8" dado stack on that saw for years without any problems. Yeah, the saw is pretty under-powered, but as long as you know that and understand that, it will work just fine.

[glenn bradley]

I also ran 3/4" dado stacks on my 1HP contractor without issue. No washer as discussed previously. The machine being up to the job may be the difference in viewpoint of the hobbyist / occasional dado'er and a pro shop where things need to move at a faster pace. I get away with a lot of things as a hobbyist that would have no room in a pro shop (or an impatient one :D). I sometimes spend more time on setup than a production shop would spend on a whole kitchen door run.

[David Kumm]

There is more to it than the power of the motor. 5/8" arbor, diameter of shaft between bearings and size of the bearings themselves are all factors that come into play when spinning that much additional weight at 3500-4500 rpm. At the very least, I'd only run a 6" dado and only once in a great while- after attending church. Dave

[Ken Fitzgerald]

I run an 8" dado set on my Ridgid TS-3650. When I get to 3/4", I do run without the outside oversized stabilizer nut without any problem.

[Frank Pratt]

That saw is not up to the job.

I ran an 8" dado stack in my 1.5 HP Jet contractor saw for years with nary a hint of drama, stress or overload. The biggest dado I ever cut with it was probably 3/4 x 3/4, so as long as expectations are realistic there should be no problem.

[Al Launier]

That saw is not up to the job.

Certainly not true! Like others above I also have the TS3650 and have used a 3/4" dado (without the flanged washer) and it worked very well.

[Art Mann]

I used a Ridgid model 3650 with a dado blade for probably 15 years. I made beehive boxes on a regular basis which required a 3/4" cut. The saw has plenty of power and the arbor is plenty strong. You just have to leave off the washer when using a full stack. It is the same way on every table saw I have ever used, including several cabinet saws. I have seen a lot of them in the 40 years I have been woodworking and have never encountered a problem.


There is more to it than the power of the motor. 5/8" arbor, diameter of shaft between bearings and size of the bearings themselves are all factors that come into play when spinning that much additional weight at 3500-4500 rpm. At the very least, I'd only run a 6" dado and only once in a great while- after attending church. Dave

[Tom Porter]

Excellent. Thanks for all the advice!

[johnny means]

That saw is not up to the job.

Hold my beer.

[David Buchhauser]

That saw is not up to the job.

Once again Andy, I must disagree! I have run the dado stack on both of my table saws many times with no problems. As others have mentioned, when running at full width both washers don't fit. This is not a problem. As long as the nut is tight and the stack runs true, this is a safe and acceptable method of mounting and using this setup.
David

[Marcus Waddell]

Hey all,
I have a similar question with regard to my Delta Contractor saw.

I know an 8” dado stack will certainly fit on my 10” 1.5 HP Delta Contractor’s Saw (Delta 34-444 early 90s model). But the owner’s manual says to use a 6 inch stack. I’ll likely never need the additional depth unless I make a dado cross cut sled, but the 6 inch Freud SD506 6 inch dado stack is MORE expensive than the SD508 8 Inch dado stack.
My saw is wired for 240V, which is supposed to make this Delta motor a 2HP, but I’m not so sure on that. It does seem to start and run much better in 240V than it did as a 120V saw, but that is purely subjective.
My question is: Will running an 8 Inch Freud SD508 dado stack hurt the saw motor (or me) or should I really stick to the 6 inch SD506 dado stack??? Thanks in advance.

[glenn bradley]

but the 6 inch Freud SD506 6 inch dado stack is MORE expensive than the SD508 8 Inch dado stack.

I assume you are referring to the current Amazon pricing oddity. The MSRP on the 8" is more and other suppliers sell the 8" for more. Amazon does what Amazon does ;-) Regardless, a 6" will do a fine job for many things. The 8" gives you greater depth and faster tooth speed. I ran an 8" on a Delta contractor back in the 70's and on a C-man contractor from the 80's without issue. That combination, like either of those saws, would not stand up to pro-shop use so I see where statements of inability or incompatibility may come from. I was just a guy in a garage.

[andy bessette]

...Will running an 8 Inch Freud SD508 dado stack hurt the saw motor (or me)...

I have been running an 8" x 1/2" Delta carbide dado on my Delta contractors saw for decades.

https://i.postimg.cc/hjhm9qFM/shop-2.jpg (https://postimages.org/)

[Rod Sheridan]

Hey all,
I have a similar question with regard to my Delta Contractor saw.

I know an 8” dado stack will certainly fit on my 10” 1.5 HP Delta Contractor’s Saw (Delta 34-444 early 90s model). But the owner’s manual says to use a 6 inch stack. I’ll likely never need the additional depth unless I make a dado cross cut sled, but the 6 inch Freud SD506 6 inch dado stack is MORE expensive than the SD508 8 Inch dado stack.
My saw is wired for 240V, which is supposed to make this Delta motor a 2HP, but I’m not so sure on that. It does seem to start and run much better in 240V than it did as a 120V saw, but that is purely subjective.
My question is: Will running an 8 Inch Freud SD508 dado stack hurt the saw motor (or me) or should I really stick to the 6 inch SD506 dado stack??? Thanks in advance.

My saw won’t take an 8 inch dado either so I use a 6 inch dado.

I’ve never needed a larger one as most dado and grooves are shallow.

Regards, Rod

[Marcus Waddell]

Thanks for the advice all. I appreciate it.

[Bruce Wrenn]

Hey all,
I have a similar question with regard to my Delta Contractor saw.

I know an 8” dado stack will certainly fit on my 10” 1.5 HP Delta Contractor’s Saw (Delta 34-444 early 90s model).
My saw is wired for 240V, which is supposed to make this Delta motor a 2HP, but I’m not so sure on that. It does seem to start and run much better in 240V than it did as a 120V saw, but that is purely subjective.There is nothing magical about that motor. Delta (Marathon) down rated it to 1.5 HP on 120, so it would work with a 15 amp plug. Truly a "smoke and mirrors " trick.

[Charles Lent]

There is nothing magical about that motor. Delta (Marathon) down rated it to 1.5 HP on 120, so it would work with a 15 amp plug. Truly a "smoke and mirrors " trick.

Nothing "Smoke and Mirrors" about it. The motor is specially wound and the windings are tapped differently to produce this capability. It isn't a normal "dual winding motor" like most dual voltage motors where you put the windings in parallel for 120 volts and in series for 240 volts. With one of these motors you get a definite increase in horsepower when you run it on 240 volts, and it isn't the increase of power due to less current flowing in the power cord when connected to 240 volt power.

Charley

[Jacob Reverb]

Interesting. Never heard of a motor like that.

I would swear that the motor in my PM 64A spins up far faster at 240V than 120 – it's really got a "snap" to it when you turn it on at 240V – but as far as I know, power output is the same. (Though I do suspect it would take longer to overheat the motor at 240V than at 120V due to less amperage going through the wires or whatever...)

[Rod Sheridan]

Interesting. Never heard of a motor like that.

I would swear that the motor in my PM 64A spins up far faster at 240V than 120 – it's really got a "snap" to it when you turn it on at 240V – but as far as I know, power output is the same. (Though I do suspect it would take longer to overheat the motor at 240V than at 120V due to less amperage going through the wires or whatever...)

Jacob, no doubt it does accelerate better at the higher voltage, that’s common, and it’s due to insufficient circuit capacity at the lower voltage.

Regards, Rod.

[Jim Becker]

Interesting. Never heard of a motor like that.

AFAIK, there were multiple saws marketed over the years (generally older machines) that had these adaptable motors with different horsepower depending on the input voltage configured. That was in a time when mass production was less affected by pennies because doing the kind of winding to support this undoubtedly "cost" more to do.

[Randy Heinemann]

I ran a dado set on my Ryobi BT3000 when I still owned it; not often but I did do it. As long as I was mindful of its power limitations and took small bites with larger dadoes, there was no problem. Nothing could be as under powered as that saw. Fact is that I usually use my router table or hand held router to do dadoes now even though I could do them on the table saw.