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?

[John Schaben]

About 1/2" down sounds about right. How much screw came through? Did the pilot hole penetrate the edge of the top? Sounds to me like the collar was set for to deep a hole or you should use a 1¼" screw, maybe both.

I've been setting the collar depth just a with a nickle lately, sometimes a little shallower. The pocket only needs to be deep enough to hide the screw head and gives you a little latitude on screw length and stock thickness.

[James Waller]

You need to set your settings on the drill guide and the drill bit according to the size of the wood you drilling into.

First let me be sure, the top/bottom boards are exactly 1" and the sides are exactly 3/4"?

If you are drilling into the 1" top/bottom, make the settings 1" and put the pocket-holes in the 3/4" sides. Use 1½" screws.

If you drilling into the 3/4" sides, make the settings 3/4" and put the pocket-holes in the 1" top/bottom. Use 1¼ screws.

[John Schaben]

Is that right??? The settings need to be based on the piece the pocket is going into. Otherwise the exit point of the screw will be off. At least thats the way I understand it.

James Waller said:

You need to set your settings on the drill guide and the drill bit according to the size of the wood you drilling into.

First let me be sure, the top/bottom boards are exactly 1" and the sides are exactly 3/4"?

If you are drilling into the 1" top/bottom, make the settings 1" and put the pocket-holes in the 3/4" sides. Use 1½" screws.

If you drilling into the 3/4" sides, make the settings 3/4" and put the pocket-holes in the 1" top/bottom. Use 1¼ screws.

[James Waller]

The settings need to be based on the piece the screw is going into. If you attach 1" to 3/4", then put pocket holes in the 1" material using 3/4" settings (box on right). If you attach the 3/4" to the 1", then put pocket holes in the 3/4" material using the 1" settings (box on left).

Click on image to make larger.

[John Schaben]

Hi James - Intresting. Not the way I interpreted the instructions. There is an advantage if putting the pocket holes in the thicker board. On the box on the right, you moved the exit point of the screw up and further from the edge of the 3/4" board. In the box on the left though, you moved the exit point of the screw out and closer to the edge of the 1" board.
James Waller said:

The settings need to be based on the piece the screw is going into. If you attach 1" to 3/4", then put pocket holes in the 1" material using 3/4" settings (box on right). If you attach the 3/4" to the 1", then put pocket holes in the 3/4" material using the 1" settings (box on left).

Click on image to make larger.

[Mark Eisen]

James Waller said:

The settings need to be based on the piece the screw is going into. If you attach 1" to 3/4", then put pocket holes in the 1" material using 3/4" settings (box on right). If you attach the 3/4" to the 1", then put pocket holes in the 3/4" material using the 1" settings (box on left).

Click on image to make larger.

[Mark Eisen]

Thanks for your replies.

What I am trying to do is what is in the box on left, 

Doing it this way shouldn't it give you more depth for the screw to bite in too? 

[James Waller]

Only thing I can say now is try different settings and different size screws on some scraps. Make sure the screw doesn't exit out the mating piece, make sure the joint is strong and make sure you get some sleep. :)

[STEPHEN R. SMALL]

The way that I see it, it is important for the pocket hole to be drilled such that the screw exits the butt joint properly centered against the piece that is being drawn against the butt.  Otherwise, the force that brings the pieces together will be unequal, weakening the joint.  The pocket hole, therefore, should be drilled in accordance with the thickness of the piece which will have the pocket hole in it.  The length of the screw will determine whether it will be properly anchored, i.e. either not penetrating far enough or penetrating too far and coming out the other side.

Someone should make a table that specifies screw lengths necessary for working with different pairings of thicknesses.

[James Metzger]

so, to sum up

Measure Jig and drill for the thickness of what your drilling into.

Pick screw for the thickness of what is being attached to what you drill into.

[John Schaben]

That's the way I see it.

James Metzger said:

so, to sum up

Measure Jig and drill for the thickness of what your drilling into.

Pick screw for the thickness of what is being attached to what you drill into.

[Ken Darga]

Stephen,

Kreg offers such info.

Go to the search box, and enter the desired info.

STEPHEN R. SMALL said:

................

Someone should make a table that specifies screw lengths necessary for working with different pairings of thicknesses.