best way to bring two different thickness boards at 90.

[John Fabiani]

I have two boards I want to bring together at 90 on long sides (makes a sort of '|_|' when you add the 3rd board). The boards have different thickness (one 3/4+ and the other 1/2-). What would be the best way to attached them. Just a rabbit and glue? Or should I try to use some sort of router bit like a 45 miter bit. I'm a newbie and just purchased the router table - haven't really used it.

Johnf

[Lee Schierer]

If you have enough material and want the strongest joint, a bridle joint would be the best. It would center your 1/2" piece on your two 3/4" pieces. In your case you wouldn't have to cut the shoulders since your pieces are different thicknesses, although the joint will be stronger if you cut the shoulders.
442361

If you don't want the horizontal board centered on the verticals, a lap joint would also work and be very strong.
442362

[Richard Coers]

How long are the boards? You building false beams? I would just use a rabbit, but make it a touch deep so you can flush trim to make it flush.

[Brian Tymchak]

I think the best way depends on what you are using it for. Assuming you are working with real lumber and not sheet goods, long grain butt joints are very strong with todays glues. If you want more strength, you can run screws into that joint. A glued mitered joint on long grain would also be strong, but unless you want the asthetics of the mitered joint, the butt joint is much easier to align and clamp.

If asthetics don't matter, I'd recommend glue and pocket screws as the strongest way to join those boards.

[Bill Dufour]

two or three boards? you are saying both.
Bil lD

[johnny means]

Just a long grain glue joint is plenty strong. A rabbet adds nothing to the strength of the joint.

[John Fabiani]

Thanks all I just use the rabbet and glue.
Johnf

[Jim Matthews]

Lee recommends my choice, the half lap.

It's dead simple to get both corners square, and if you clamp them on a flat surface they should be pretty much planar. Use each side of the joint to mark where the cut should be - no gauges necessary. Your router table should make short work of cutting away waste.

It's VERY strong.

Once everything is glued up and dry, you can flatten the assembly by sanding or planing.

[glenn bradley]

Thanks all I just use the rabbet and glue.
Johnf

That's how I would go.