Joining Different thickness materials Using a Kreg Jig

[Mark Eisen]

I want to build a cabinet that has 25mm (1") top and bottom with 19mm (¾") sides.
I set the Kreg jig and drill both to 25mm (1")and when I put in the screw, it came out the side of the base about 12mm ( ½") down.
I am using 38 mm (1½") screws.
What am I doing wrong?

[Bruce Wrenn]

I'm not good at converting from metric to imperial. I ALWAYS do a test piece when changing anything about my Kreg Jig though. Better to have a hole in some scrap than my project.

[johnny means]

This is sooo hard to explain, but here goes. Jig placement will determine where on your edge your screw exits. Set your jig for 19mm and the screw will exit at about 9.5mm. Remember, the jigs angle is fixed, so the further you start from the edge of the board the further you have to go through the board to get to the edge. Depth stop setting will effect how much screw comes out the other side of your pocket and in doing so will effect how much further toward the other side your screw goes. Longer screws will also travel further toward the other face. Taken to the extreme both of these will eventually lead to the screw exiting the opposite plane.

You my friend hit the trifecta. Your jig was set wrong, should have been placed for 19mm, so it would aim the screw for the center of the board edge. Your bit was set wrong, thus drilling to far, in effect making your screw longer. Finally, your screw was to long meaning it kept going right on past the the other side of your work piece. Next time set your jig up for the thickness of the piece being drilled and use the prescribed screw for that thickness. Unless, going into a thinner piece which will require a shorter screw. In short, you should have set up for 19mm and used 1.25" screws.

[Matt Meiser]

You want to adust the jig so that the screw exits the drilled piece in about the middle. Then put in a screw in just that piece and find what screw length will be just short enough not to break through the other piece.

And yes, use some scrap to test everything first!

[Mark Eisen]

Thanks for your replies,
I stuffed up totally I was thinking that you set it up for the piece that I was screwing in too.