chip out while using Dado

[Rob Franz]

Anyone have any tips to stop tear/chip out while using Dado's?
I've been running into a lot of it lately, making Craftsman style picture frames using walnut or oak.

Presently, I use a backer piece of cheap pine, so that the good wood isn't the last thru the blade. Works pretty good.

Must be some better tips though.

Rob

[Jim Becker]

Using a backer at the terminus of the cut is always a good idea since that's the one place that zero clearance inserts, pre-scoring and other techniques don't necessarily cover. Your particular dado set and how it's ground can also have an effect. BTW, using a router for the same work has the same risk...and the backer is almost manditory there.

[Stephen Edwards]

The backer piece is certainly the way that I recommend. Depending on the application (meaning it won't work in all situations) I've found this to be helpful, too:

I do as much of my dado work as possible, especially if it's across the grain, BEFORE I size the piece to it's finished size. For example, If I'm shooting for a finished width of 6 inches I'll get the pieces sized to 6 1/8 or 6 1/4 (the amount of oversizing can depend on the type of wood you're using). Then, do the dado. Finally using the table saw and/or jointer take it down down to the finished 6 inches. Usually, that will remove any tearout at the end of the dado. That technique has solved the problem for me in several appications.

[keith ouellette]

It could be the dado blade. The first one i bought was very cheap from Lowes. It was horrible. My Freud works much better.

I don't know how how long you've had the dado set you are using but it may need a good cleaning.

Try just a light pass first, just enough to break the wood. Then cut the dado.

[Lee Schierer]

One way to stop the tear out completely is to hand saw the last part of the cut where the blade will exist the wood. Use a fine tooth saw.

Tear out on the face can be eliminated with a zero clearance insert as others have said. Just make sure the board is held tightly down against the table. Another way to eliminate tear out is to cover the cut area with masking tape. Regular masking tape works better than painters tape. After the cut, peel the tape toward the cut line not way from it.

[Cliff Rohrabacher]

If you took a cut with the dado that is deeper than that which you are now doing you'll get chip out.

When I'm doing it with a fixture and the fixture is the backer I'll glue a piece in the old dado or just shove some epoxy putty in and smooth it flat.

If you are working Oak or other very hard chippy hard material and the backer is pine you may be finding the harder wood is pushing into the pine and chipping out a little. In such an event use a harder material for the backer and make sure the work is hard up against it.

[Scott Vigder]

I try to always use the same stock type for a backer as the stock I'm cutting.

I also learned that a good Freud dado set cut circles around the cheaper adjustable set it replaced. Today I was using the Freud to remove 1-5/8" of material and I did it in three passes, with nary a chip out of place.

[John Hixon]

I just saw this from shopsmith

http://www.shopsmithacademy.com/SS_Archives/SS112/SS112_Dadoes_&_Rabbets.htm

Basically, scribe lines at the edge of the dadoes with a work knife. Clean cuts then happen. Interesting video.