Jointing with a disk sander--another look

[Highdesertww]

I read that one cannot joint a stock with just any disk sander. To joint with a disk sander, it has to have a slight shallow cone shape, about two degrees.

So one mounts such a disk on the table saw and tilts the arbor two degrees.

I understand the mechanics of this but I am not sure that this is practically important.

In a plain (plane) disk sander, one must avoid jointing more than the radius to avoid upward spin of the disk. One can readily avoid this without any cone shape of the disk.

One joints with a slight angle, as much as 5 degrees off. One accepts the "coving effect" in jointing, that is hollowing in the middle of the edge of a stock for jointing. Cosine 5 degree is 0.996. 4 thousandths out of a one-inch stock, 3 thousandths out of 4/4 stock.

Moreover, one mostly  joint 4/4 stock for a wider board. One can set the table 3/8 inch lower than the center point of the arbor of the disk. This way, both faces of the stock will be the same and the deepest hollow of the stock will be at the center of the edge of the stock. When gluing,  the pressure will seal the 0.003 inch.

I hope I am right.

[BloomingtonMike]

I feel like i came into a class that was on chapter 5.

Why are you using a disk sander again?

[Ken Vick]

I used to have one of the Craftsman ( I think ) 2* beveled sanding discs that I used on my TS maybe 30 years ago.  It works.  And the reason it works is that the bevel along with tilting the disc by 2* you create a top dead center spot which is the only part of the disc that contacts the wood.  If you look at the sanding lines on the edge of the wood they will be straight along the length of the wood, not swirled.  The jointed edge is not scalloped but a true 90*.  It is a somewhat slow method and only to be used if there is no jointer or you are not proficient with a hand plane.  Ken

[MikeBob]

Best there is!!! I dont know if it will work on other then a SS, but they are great, cheap used, but not good as a table saw, I have 5 of different eras.

http://www.shopsmith.com/ownersite/catal...anding.htm

[BloomingtonMike]

Or dont own a router and straight bit and few pieces of sheet stock.