The Router Bit Basics
*** This post is courtesy of Tom Iovino of Tom’s Workbench ***
So, you have a router. Great. It’s a very useful tool, allowing you to cut joinery, shape moldings, thickness boards and a host of other uses. Maybe yours has an ultra-smooth plunge action. Perhaps a soft electronic start. A massively useful edge guide. Go ahead. Open the case on your router and breathe in the multitasking goodness. Take your time. I’ll give you a minute…
Oh, wait, there may be one little detail you have overlooked, isn’t there? That’s right – the router itself has to be paired with router bits to do its woodworking goodness. Without router bits, your router is really a high-tech, tricked out paperweight.
So, what can you do to remedy this situation? There are two different routes you can take. First, you can buy bits one at a time as the need arises. But, if you do that, there’s a chance you’ll be mid-project without the bit you need. The other option is to buy a set of bits to have the basics on hand. In this scenario, you’ll discover that you use some bits until their carbide is about to fall off while others sit idle in the case. I’ve approached the router bit buying routine from both sides as my woodworking skills have developed and have arrived at a third avenue of choice. That would be to ask your woodworking friends what bits they use the most and pick those most useful up first.
What are my most used bits? I’m glad you asked. They include:
A 1/2” straight cutting bit. If you are going to route dadoes or rabbets, you could do a whole lot worse than this workhorse. If you are working with material thicker than ½”, you can cut your dado and then use the bit to rabbet the material being inserted into the groove so it fits the channel. This bit can also be used to set your router table up as a jointer using an offset fence.
A 3/8” up-spiral bit. Your plunge router makes a very handy and effective mortising machine. Since I frequently use 3/8” mortises when joining ¾” material, this bit gives me the dimension to shoot for. The up-spiral bit helps eject the router shavings effectively while you are plunging the router.
A 1/2” top bearing pattern following bit. If you want to ensure that identical project pieces are truly identical, cut a template from an inexpensive sheet material such as MDF and pattern-route the pieces to shape. A very cool technique that will improve your woodworking. A bonus use – you can run this bit against a straight edge and cut dadoes in sheet goods.
A 1/2” round over bit. Cut pieces of wood have very sharp edges on them. Easing these edges makes your projects more comfortable to handle and the rounded over edge is less likely to splinter if handled roughly. You can adjust how much is cut by changing the amount of bit that’s exposed for cutting.
A 1/2” cove bit. This bit cuts the mirror image of the round over bit, scooping out an area of wood. Combining the round over and cove bits creatively can allow you to cut some very cool looking moldings with basic bits.
A 3/4” chamfer bit. In addition to knocking a 45 degree edge off of projects and moldings, you can also use this bit to ensure mitered project parts are accurately milled to 45 degrees, ready to be joined into perfect, airtight miters.
A 3/4”, 14 degree dovetail bit. When you buy a router jig to cut dovetails, you probably won’t be using this bit to do your cutting. Most jigs require different sizes or diameters of bits to work properly. However, this bit can allow you to master another awesome joint – the sliding dovetail. Once you learn how to cut one, you’ll be hooked.
*** Specials thanks to Tom Iovino, a true Shop Monkey, for this post. He will be providing posts on a monthly basis for Eagle America, check back again soon. ***