attaching 3/4" board to 1 1/2" board

[Rusty Paull]

I'm making a chair and want to attach a piece of 3/4" between to chair legs that are 1 1/2" what should the jig be set at and what size screws should I use?

[michael evans]

Hi rusty , i am no expert on woodwork but allways have a dry run at anything cutting, morticeing,routing. Attach a rough piece of stock obviously the size you require, too the other piece of stock see how it goes.[EXPERIMENT] I guess your end up with a inch /inch and a quarter screw .Regards mick .

[KregRep]

Rusty,

What settings and screw size to use with dissimilar thicknesses depends on a number of factors.

First, I usually set the jig to match the thickness of whatever I'm drilling the pocket in. I assume this will be your 3/4" piece, so set the jig for 3/4". that way, the screw will exit at the appropriate spot--roughly centered on the thickness of the stock to minimize splitting risk

Now for the screw length. You're always safe using the screw length recommended for the thinner board--3/4" thick in this place, which means a 1 1/4" screw. If your thinner piece is meeting the thicker flush on the one face, stick with the recommended length. If the piece is inset from the edges, though, and you want more screw for more confidence, you can go with a longer screw, such as a 1 3/8" or 1 1/2".

I hope this helps. For more help, check out this back issue of our Kreg Plus newsletter. http://www.kregtool.com/files/newsletters/kregplus/february12.asp. It's all about screw length. Also, there's a link to a video about selecting screws. It goes through lots of information, including working with different thicknesses.

KregRep