A pattern-cutting router bit uses a bearing to guide the bit, and the bearing and cutter should be the same size. Find out how to make a pattern or template before using a pattern-cutting router bit with help from an experienced woodworker in this free video on router bits.
Hi I'm Dave Trull with The Trull Gallery, a custom furniture shop in St. Petersburg, Florida and I'm going to show you how to use a pattern cutting router bit. First of, we'll start with the bit, I already have one here in my router. And as you can see, there's a bearing that guides the bit, and the cutter, the bearing and the cutter are the same size. So what the bearing feels, the cutter cuts. So you're working with a jig or a template, that are the exact shape and size of your final piece. Another option is, basically it's the opposite of the flush trim bit. The difference being, rather than the bearing being on the shaft end, it's on the tip end. And the difference between the two essentially is, which side of your work, your pattern goes on. The first thing we're going to do is, we're going to make our pattern or template, and I've got a template here, simple curves that I use on a lot of the aprons of my furniture. And I'm going to take it to my stock and line it up, so that my ends and bottom are square to the stock, and I'm going to draw a line on my material. Then I took it over to my band saw, and I cut just outside the line. And you can see, I try to keep it close to the line and trying not to leave much more than a sixteenth of an inch or so of waste. If you leave too much waste, it's extra work with the router. And it can lead to some burning if you're not working and paying attention to your speeds and such. The next thing we want to do, is clamp our stock to our template and our bench, making sure that everything is lined up. A lot of times, I won't even clamp my material to the template, I'll use double stick tape. A couple pieces of double stick tape, making sure it's good and secure, will hold your template and your stock together. And then you just need to clamp down to your bench. One thing you want to make sure, is that your cup line is clear of your bench, so you don't cut the bench itself. What I'm going to do for the demonstration purposes, is just do a portion of it. So you can see where my cut line is from the band saw and how rough that is, in comparison to how smooth and clean the line is from my template guide. The next thing we want to do, is to set our bit height. What we want to make sure is that our bearing on our bit is riding right against the template that we've made, and then go ahead and lock down my depths. Go ahead and put on our safety gear, and make our cut. Now we've got a nice smooth surface, parallel with our guide, and you'll see a couple of things. It's a much smoother curve, it's right where I line. And we could have easily done this whole thing in one pass, cleaned everything up. The other thing yo might be able to see, is that I've got a one inch board but a three quarter inch cutter. So I still have a little bit of stock here at the bottom, that's not a problem. To clean that up, we can go ahead and pop it back on our table, and we're going to make the exact same cut. This time, instead of using our template, we're going to use the upper portion of our stock. Now you can see that we have a nice, smooth surface, all the way across, you can see here, where I've left a little bit for comparison. If you can't get longer bits, if you're doing a stock of greater thicknesses than this, or you can just do it in two passes, like I've done today. That's a little bit of information on how to use a pattern cutting router bit. I'm Dave Trull with The Trull Gallery, the fine art of furniture making.