Expert: Jamie Yocono - 7/27/2007

Question
I am building a cabinet with 2 fully extending shelves that is also serving as a bench. I just need to finish putting the doors on with European Full-inset hinges. The dimensions for each door are 22 1/2" wide & 17 5/8" tall. I was originally going to use the same 3/4" oak plywood I used for the top of the cabinet, but figured with doors that wide, the plywood would not only make the doors too thick (especially considering I was going to use 5/8" thick moulding to make them look like regular cabinet doors), but also probably put too much strain on the hinges. I saw your recent answer to a question regarding whether to use a table saw or a router to build glass cabinet doors. I have the table saw, a Ryobi 10in saw, but not the router. The fence holds fairly well, but I'm still just getting used to it. You had mentioned using half lap joints. Can you help me understand how to cut those?
Sorry of I put in too much info.
Thanks

Answer
Hi Michael,

It's pretty easy to cut half lap joints on a tablesaw, and once you understand how to do it, there are ways to cut your time down even more.

Just for the sake of simplicity, let's just assume you're using 2" stock for the stiles and rails, and it's 3/4" thick.  For a half lap, you're going to be removing half the thickness from both pieces of wood, where they intersect at the corners.  The material (stiles and rails) are cut the full length and width needed. So if your door is 22 1/2 x 17 5/8,  you'll need 2 pieces each length.  

I like to make the door slightly larger, and then trim it down when it's glued up. So you might want to make it, for example, with 2 1/8" stock, and make it about a quarter inch larger all around. Then when it's dry, you'll trim that 1/8 inch off all 4 sides and end up with the size you need.  (I'm trying to keep it simple.)

Anyway, The concept is that you're going to lower your tablesaw blade down to half the height of the wood. So in this case, it will be set at 3/8". Using your miter gauge (make sure it's square to the blade) you're going to be cutting half the material off all the pieces.

Look at this page for an illustrated view:  http://sawdustmaking.com/woodjoints/halflap.htm

Scroll down a bit to see Figure 29 and you'll see the exact joint I am talking about.

Cut all the corners, and put the boards together to form your door. See how they go together?  OK, here are some tips to save you time and energy...

Lay your doors out with the 4 pieces of wood, and put an X on the area to be removed. I like to do this so I can choose the grain I want, as well as the orientation of the joint itself.  When you start cutting your material, it's easy to figure out which side of the board to cut.

Instead of cutting the pieces individually, use 2 wider boards, that are twice the width you need, plus a little for saw kerf waste. So if you want 2" door members, use a board that's roughly 4 1/8" wide. Cut a half lap on each end. Then rip in down the middle and you'll have 2 matching pieces. Sweet.

Another tip- a VERY easy method for cutting the slot for your panel is with this bit:
http://www.leevalley.com/wood/page.aspx?c=2&p=47818&cat=1,46168,46176&ap=1   It's listed as a box slotting bit, but works fine for cutting the 1/4" slot for your door interior. It's safe and easy to use. I've tried a lot of methods and I highly recommend this.

When gluing up this door, it's going to take roughly 8 clamps. You'll need 4 bar clamps. I like to use 1/2" bar clamps for this, since you only need to pull the door together and square.  You'll need two on the bottom to hold the door in one direction, and then two on top, to pull the joints together in the other direction. Once you have the door pulled together and square, you'll need 4 identical C-clamps, or something similar. I like those little Bessey clamps that cost about $5. I probably have 30 or 40 of them just for stuff like this. While the door is pulled tight and square with the bar clamps, put one of those smaller clamps at each corner, clamping each corner joint together. Then remove all the bar clamps and lay the door down on something flat, like a workbench, tablesaw top, or even the floor.

The reason you need 4 matching clamps is that they are resting on the surface below, holding the door flat. If you use different clamps, the door will sag or bow a little, and when you unclamp it, your door will be glued up wonky. Yes, that's a technical term for a piece that you'll want to throw against the wall and have to start over.

Anyway, I hope what I've described here makes sense. All of my previous mistakes should make door making much more simple for you. If it's possible to screw it up, I'm sure I've done it once or twice. So I hope this helps!

Good luck, write back if you have any questions, or just need a pep talk. :)

Jamie Yocono
Wood It Is! Custom Cabinetry
Las Vegas, NV
www.wooditis.com