Wobble dado blade

[Rounder]

I have the SD206 stacked dado set for my BT3100. Last night in my woodworking class, the instructor used a wobble dado blade. I didn't get to see the dado it made up close, but it appeared to do teh same job as my stacked dado would have. It also appeared a lot easier to set up.

Why are stacked dado's prefered to wobble?

[Eric]

The wobble dados that I've seen don't leave as clean of a cut as a stacked set. The bottom of the dado will also be wider than the top because of the way the wobble dados wobble.

I think they're fine for doing shelf dados and the like, although, I think I've read on the forums here that they shouldn't be used on the BT3.

[don_hart]

Two major reasons.

1. They greatly increase the vibration of the saw. If you have a massive cast iron cabinet saw this is not as big of a deal

2. They will make fairly decent dados but only within a limited range. The farther you get from the dado width the unit is really deisgned for (usually 3/4") the more rounding you will get on the bottom of the dado.

[John Hunter]

I have both. The wobble (a craftsman) is fast and easy and gives me good cuts for the designed range. http://www.sears.com/sr/javasr/produ...id=00903261000

[Popeye]

I have the high end Craftsman 3 blade adjustable George. That may have been what he was using. Works as well as a stack IMO but I'm glad I didn't pay the $200 they get for them. Alittle horse trading on my part. Pat

[LCHIEN]

Eric was wrong. They do leave perfectly vertical sides.
However, it is true that they leave a slightly rounded bottom,
the curve has a radius of 4".
For a 8" wobble dado cutting a 1/2" wide groove, I calculate the center bottom will be .008" lower then the sides. Its small (1/128") but visible rounding.
I have a Sears twin-blade excalibur. Doesn't shake the saw.
If you pay $10-$20 for one then it will probably shake but if you pay $75-100 for one then it will be well balanced.
Personally I think they are over-villified, in general.
But it is a bear to get them on the BT3 arbor with the blade shroud!

[jhart]

Also have the Sears excalibur, which I use on my RAS. Just bought the Avenger 6" dado set during the winter. Without a doubt, the wobble is easier to set up and use on the RAS, than the Avenger set. Avenger set did a great job on the dados I did on a set of bookcases. They came out perfect. The wobble set does not do as great of a job, but usually I'm not looking for as precise a cut with the wobble and using it on smaller pieces (short dados).

The excalibur cost about $90.00 a couple of years ago and the avenger was on sale at Rockler's on Thanksgiving weekend for $29.95.

[JimD]

I have a wobble dado that is ground to produce a flat bottom dado at 3/4 inch width. Most will produce a flat bottom at something like 1/4 inch. At any other width, the grind of the teeth is such that there is a curve to the bottom of the dado. I find it more difficult to adjust to a specific width, however. I have to remove it from the arbor, loosen a couple of screws on the sides, rotate one side versus the other a little, tighten the screws and reinstall on the arbor. I never know exactly what affect I will have on the width of the dado. With my Freud stacked set, I measure the width of the dado I cut to test the width and add or subtract shims of known thickness to get what I want. I only have to remove the outer blade, most times, for shim insertion. I hardly ever use my wobble dado mainly because of the difficulty in adjustment. Maybe I'll give it a try this weekend. If I could get it set up for one type of plywood or solid wood and then just leave it that way, it would help. I think my wobble dado also tends to cut more roughly because of fewer teeth but that can be somewhat offset by feeding the stock more slowly.

Jim

[Eric]

Doesn't surprise me that I was wrong Loring, but the dadoes that I was getting from a wobble blade that a friend of mine had on his Delta did give a wider bottom.