The whole boring slots thing didn't work out well for me for those backs. I had to do a work-around.
Holy moly!! I've had a bad cold for a few days, and when I mentioned "slot boring", I'd just woke up and was still under the influence of Nyquil! What I really meant was..POCKET BORES!
I don't know if you understand what a Pocket bore is, but they work really well...if you have the tool. What they originally were made to do is fasten Face Frames for cabinetry together. But just like the bisquit's, you can use it to fasten panels together too.
Most shops have a table mounted machine to do this. And it works great, although it's hard to justify the expense unless you are doing tons of face frames. But Kreg manufactures a hand held jig with tapered bits for doing them. I've used it and it works good too. A bit of a hassle, but if it's your only option..then ya gotta do what ya gotta do!
Anyway, here's the tool.
Pocket Hole Joinery with the Kreg Jig - Rockler Woodworking and Hardware
Ok, as to your desk/racks design, I see a couple of things. First off, IF..you are planning on keeping the racks in that position, I see no reason for legs under the desk. Just use the racks as the legs. Even if the racks were at an angle to the desk.
Second, as to the original question about fastening the tops of the rack cases...like I said, I was under the influence..
I completely forgot something.
In reality..this is what most pro woodworkers do. At least me.
This system is called SDR..or STOP DADO's and Rabitts. Of course, you don't have to do this, but I thought I'd turn you on to this just for drill.
Ok, here is your completed unit.
I looked at your Sketchup, and decided to draw the whole thing in order to illustrate various concepts. I noticed three things.
1. You have an exposed top edge of something right under the top.
2. Your toe kick is angled
3. You have a crosspiece below the equipment.
So, in this case, regardless of what I told you earlier, I would simply use two pieces of MDF as a web, and use them to fasten the top.
Furthermore, these told me you could use the SDR system for this. Basically, this is how it works.
To REALLY make things come out clean and simple, I would use STOP Rabitts on the top web panels and use Stop Dado's on the ends, and PRE edgeband the front edge of the front top web panel.
The issue here is machining things, so you can
PRE-EDGEBAND prior to assembly. This means, if you dado the bottom and SUB top INTO the Ends, you do NOT want the dado's to "run through"..that is, they have to STOP, before they reach the edge. So, the Ends are machined with "Stop Dado's" and complementary, the "SUB-top", in this case a couple of stretchers or web, and the bottom are STOP rabitted. Like this.
Here are the ends...
Here is the bottom
Here is one of the sub top web pieces
[/IMG]
This is the standard way to do store fixture casework. The cabinet actually has either a "sub top" or a web/web frame. A webframe is the old way of doing things before sheetgoods were available. Most modern big shops use a full panel for a "sub-top", because MDF is cheaper than labor. But small shops usually try to save material. Hence using two pieces of scrap MDF or such. Now, I see in your design you have the edge of something exposed just below the top panel. This could be an edgebanded Web piece.
Here is the machining info. Notice the "rabitts" STOP, which allows a portion of the material to interface the dado on the ends. This also allows to PRE edgband the material prior to assembly. Makes things come out real nice if you align things correctly during assembly.
... like this...
Then you attach the rest of the stringers..at the base, and the panel below the equipment, and at the top rear. These could be cleat mounted, or pocket bored, or nailed via nail gun, or just glue, or even screws. However ...
Myraid, as usual, everything depends on the details, and the devil is in the details. And you are the only one who determines what details you want to use. Some people don't mind nailing right through finished surfaces and then filling prior to staining. It just depends on what you like. And there's lot's more to this system. If you are interested, just holla.
Well, I'm outta time. Hope this helps a bit with your planning.
I just HAVE to stain it fitZ! I'll put plenty of poly on it for mass protection. I think I'll secure the top with a couple of cleats and maybe some metal angles for good measure. The whole boring slots thing didn't work out well for me for those backs. I had to do a work-around.
