Step 1: Preparation and Planning
- A Kitchen cart (ideally solid wood)
- A bowl
- A router - this can be rented from most hardware stores, if you don't have one. You may also need a piece of wood to attach to your router to serve as the pivot point.
- Two bits for your router: one regular bit that's long enough to cut through the depth of your cutting surface, and a rabbeting bit the size of your bowl's lip.
- Some scrap wood at least half the size of your kitchen cart's top.
- 4 screws long enough to attach your cutting board to the scrap board.
- Measuring tape
The first step, clearly, is to get a kitchen cart. It's good to find one whose surface is not too thick, as a really thick cutting surface will require a larger routing bit, or more creative routing. The Forhoja cart's surface is solid wood that's about an inch and a quarter thick.
The next step should be to get a bowl (or bowls). It will be important in the next step to know the bowl's diameter as well as the width of its lip. I found two bowls that have the same width lip and the same diameter, but different depths, so I can change the bowl depending on the purpose or amount of food I'm cutting. It is also convenient to get a bowl with a flat lip, so that finely chopped food will not get hung up on the curve of the lip.
Finally, you want to think about the way you chop vegetables; this will determine into which side you want to embed the bowl. For instance, I tend to cut right to left, making it more comfortable to place the bowl on the right, so it's easy to sweep the produce into the bowl when I'm done chopping.
Step 2: Measuring and First Stage Routing
First, measure where you want the center of the bowl and figure out the radius of the bowl. In addition to clamping the cutting surface to the scrap board, it is important to secure the piece that you'll be cutting out. You can do this by screwing the cutting surface (within the bowl's radius) to the scrap wood, as seen in the accompanying image. If you are going to make markings on the cutting surface, it's best to make them on the underside of the cutting surface. For this first step, it does not matter which side of the board you start cutting, as you are just cutting straight through the entire depth of the wood.
Attach the router to the cutting surface so that it pivots around the center of where you want the bowl. Keep in mind that you don't want the routing bit centered on the radius line, but rather you want to subtract the radius of the bit so that you don't make the hole too big!
If you're familiar with using a router, this should be no sweat. If it would be your first time, you might want to practice a bit on some scrap wood.
Step 3: Second Stage Routing
1. Making sure you have the right sized rabbeting bit (you can ask your local hardware store guy to help with that, if need be); and
2. Making sure you make the second-stage cut on the UP side of the cutting surface. Whereas in the first stage, you could cut in from either end, in this stage you should cut down into the top, for obvious reasons.
Once you have the right bit, go ahead and rout. You won't need the router to be attached to anything this time, because the rabbeting bit just follows the inner contour of the hole you've already made. The router has a manual setting that allows you to set the depth to which you rout. This is the way you will control the depth of the lip you make.
Step 4: Finish It Off!
You might also want to line the scraps drawer with some waterproof material such as a stiff plastic that you can remove and wash out when necessary.
You can find other bowls that also fit in the hole you've made. I've found the deeper bowl is good for baking cakes or doing other things that might require, say, holding up an electric mixer for a significant amount of time. The way this worked out, it works practically as a stand mixer! If you made the inset ledge really well/tight (which I did not, as you can see below), it could be difficult to get the bowl out, in which case you might want to make a little grove which you can use to lift out the bowl more easily.
You can also add some extra touches, depending on your needs. On the right side of my cart, for instance, I installed a hook on which I can hang my pot holders.