Problem with stacked Dado & Delta CS

[Conrad Aquino]

I finally broke down and bought my first stacked dado set (Freud SD 508) last month, and I'm just now getting around to using it.

Previously I had been using an ancient Sear's wobble dado blade and I would true up the bottom cut with my router, if it was really needed.

The saw is a 21 yr old Delta 10" CS, I wanted to use the set to cut a 3/4" Dado to recess some shelf brackets and when I attempted to put the stack on the arbor, there was hardly any threads left for the arbor nut to engage on, in fact I felt it was too unsafe with the amount of threads (2 or 3) to even attempt using the set up.

Question, have I messed up by purchasing the wrong dado set (1-1/2 motor horsepower not withstanding) for a CS? The Saw's manual made no mention of a particular size to use, in fact in the back under the list of accessories available, both a 6" & 8" stacked sets are listed. Is that the possible answer, I'm stuck having to use the sets made by Delta to work with their saws?

Or are contractor style saws known for having shorter arbors than cabinet saws and I just need to live with that fact and use my router with a 3/4 straight bit to cut the dado instead?

I did a search of the forum and didn't find anything (at least with the search arguments I used) regarding this.

Thanks,

Conrad

[Hoa Dinh]

I don't know much about the arbor on a 21 yr old Delta CS. This is what I can tell you:

1. In terms of power, you should not have any problem with an 8" dado set. My old table saws were a 1 HP (12A @ 120V) Craftsman and a 1.5 HP (12.8A @ 120V) Delta. They did not have any problem with my Jesada 8" set.

2. You don't need to use the large arbor washer (flange) for a dado set. That will ease the problem with the arbor length, maybe even enough so you can cut 3/4" dado.

[Larry Fox]

Conrad, I have the same sort of problem with my Dado set. I have the Forrest dado set and a Unisaw (which is a cabinet saw) and I can't stack both blades and all chippers on withough their being so few threads left that it does not feel safe - at all. While I can't offer you any solution or good advise - I have always wondered about it as well and am interested in reading responses from others regarding their expiereice and opinions about why it is the case.

[Doug Shepard]

With the full set of chippers, I cant use the large washer with my PM66 and Forrest dado set either, but dont have any problem getting the nut on even with the end of the arbor without it. And the HP vs dado diameter issue is really only relevant if you're trying to make a dado to max depth capacity (or at least deeper depths) of the dado set.

[Charles McCracken]

Conrad,

I think Hoa has the answer in that you don't use the outer washer with a stacked dado unless the saw manufacturer indicates that you need to use it. Also, IIRC, Delta offers a special nut just for use with stacked dado sets. Either way, you should contact Delta to find the max width that they recommend for that saw.

[glenn bradley]

My older contractor saw maxed out with a usable 5/8", my newer one can get to 3/4". My hybrid will take up to 13/16 which is fine but still is shy of the requirement for a dial-a-width ;-( so I guess a stack will have to do. So in a word, yes, some arbors are too short for a full stack.

[Larry Fox]

The not needing the arbor washer is the answer to my dilema. Never dawned on me to not use it.

[Conrad Aquino]

Thanks everyone!!

Now I know it's the nature of the beast rather than a case of having the wrong set for my saw.

The Sears wobble dado blade I have has the arbor hole counter sunk (set back) in the outward hub so there's an ample amount of arbor protruding for the nut to screw onto, and it will dial up to a 3/4" dado with no problem. It just does not cut a flat bottom.

On my inital attempt, I did leave off the large outside arbor flange and had only the nut against the outer blade. I guess what surprised me about the encounter was having a dado set capable of cutting a larger size than what my saw arbor could handle, so I thought I had bought a set made for a different saw.

But when I think of it, I guess stacked dado sets are basically a "one size fits all", and you do with them what your saw allows you to do, and the other chippers stay in the box.