A while back I posted a method of making one of my best selling items at shows, a simple cracker holder. Update, I make them on a Shopbot CNC router now, and thought some might like to see the process.
Here is the bot. It comes from Shopbot with a 1/2 inch thick aluminum table drilled with 1/4 x 20 holes so you can attach your own table depending on what kind of hold down setups you will be using. I opted to build this T-track table on it because I will be using a lot of product specific jigs and needed lots of options orientation-wise to be able to attach the jigs to the table. So far it has worked out great.
Here is the bot with the cracker holder hogging-out jig attached to the table ready for a blank.
Here is a pic of that jig loaded with a blank ready to hog out. That small piece of aluminum angle iron in the bottom right corner of the jig is how I orient the router/bot to the jig when I set up for this job. I'm using a 1/2 inch solid carbide spiral upcut bit for the hogging, and I move the router close to the area of the angle, then nudge the jig till it's touching the inside of that angle. I then tell the bot that that point is zero. The program I wrote assumes that, and it then moves specific distances in the x and y axis to do the hogging. You can't see the bit in this pic because I still have the dust collector shell around the bit. I will remove that for a few pics so you can see the action better.
I played around and tried lots of methods to actually hog it out, and through trial and error came up with a method that make the cleanest cuts in most kinds of wood without the bit burning any corners or bottom. Method I came up with first goes around and bores a hole at each corner, and then works around the inside of the blank in 5 left and right passes to clean out a layer. The area I am hogging is 7/8 inch deep, and I found that I could do the whole hog out with one 7/8 inch deep cut, but I had to slow the bot down to do that, and it tended to burn some wood like maple and cherry. So I decided to write the program to do the hog in 4 "layers"... 3 hogs each 1/4 inch deep, and then one final 1/8 inch deep final hog. At the speed I set it for this job, it takes about 2 minutes start to finish all four passes.
Here is the finished rough product ready for the next step, sanding and 1/8 inch roundover all around, then drill the hole in the handle, and finish it with walnut oil. The one on the bot is cherry, the row of holders on the table are already oiled, they came from red oak I milled from a log this past January. It dried fast, was down to 14%MC already, and for this project that's fine to use right off the stickered pile.