Trim Router Techniques

The trim router is a tool that might not get much use in some shops, but it is unique and surprisingly versatile tool. They’re lightweight, surprisingly powerful and small enough to go places other bulky routers can’t. If you only use yours for trimming plastic laminate, think again.

Here are 10 ways to get that half-pint router out of the cobwebs and into the action much more often.

makita trim router

#1 - Duplicating Parts

Trim routers with top-bearing pattern bits make short work of routing out wood around a template, perfect for making multiples of the same item. OK, Chris, you really just mean template-routing, right? Yep, good old garden variety template work isn’t just for mid- or full-sized routers. Think about it: it doesn’t take 2hp to shave off 1/16" of material to bring 1x or thinner stock flush with the edge of a template. A trim router equipped with a top-bearing pattern bit will do this job just fine. Or, mount your template below the workpiece and use a long flush-trim bit instead. It works so well you might wonder why you need a bigger, heavier machine to do it — especially on smaller or narrow parts.


#2 - Cutting Hinge Mortises

Making a door hinge mortise can be done with a chisel, but it's more efficient with a standard trim router. I use a 1/4" straight bit inside a standard guide collar for this task. With this setup, hinge mortising becomes a standard template routing operation. I make a U-shaped template from scrap and fasten it to a base that I can clamp against the door frame. The template opening is sized to match the hinge leaf proportions, plus the amount of offset between the outer rim of the guide collar and the bit’s cutting edges. The template not only creates one uniform mortise after the next so you can cut them production style; it also creates a larger platform to help steady the router. Many trim router models come with bases that take guide collars; if yours doesn’t, you can usually buy an accessory sub-base that will. Or buy a universal sub-base for larger routers, cut it to size and screw it to your machine.


#3 - Profiling Edges

Laminate trimmers are perfect for edge profiling, provided you make several careful passes to reach your cutting depth. A laminate trimmer is a router, after all — just a small one. And, with horsepower ratings on some of these machines achieving one or even 1-1⁄4hp peak, that’s plenty of power for routing edge profiles. I regularly grab mine for cutting tiny chamfers or roundovers to knock off sharp edges. In fact, I keep a 1/8" roundover bit in a spare trim router all the time so it’s ready when the need arises. But you don’t have to stop here. Larger ogees, coves, beading and other edge shaping is certainly possible, too. Just follow good routing practices and use a sharp, clean carbide bit to remove the waste: start shallow on the first cut, and make a series of deeper passes after that, removing more wood each time. Make the last pass just a whisper deeper to clean away any last burn marks that may still be present.

ridgid trim router

#4 - Cleaning Veneer

Trim routers can help bring edging into alignment with a solid-carbide laminate trimming bit or a sheer flush-trimmer. Occasionally, I make veneer from pieces of resawn stock. I leave the veneer panel larger than necessary when applying it to its substrate. Then, a quick pass with a trim router brings the veneer edges into perfect alignment. With thin veneer, you can use a climb cut when necessary and not be concerned with the router grabbing erratically. It’s a good way to keep the veneer from chipping or tearing out at the corners. A solid-carbide laminate trimming bit or a flush-trimmer with a sheer cutting angle are both good choices for this application.

festool trim router

#5 - Trimming Shelf Lipping

Rather than trying to sand veneer and risk damage, a trim router can cut the solid wood lipping flush. One of my favorite uses for a laminate trimmer is shaving solid-wood lipping flush on plywood shelving. The Festool MFK router shown here has an optional base that lets you flush-trim using a straight bit with the router resting on the shelf face for maximum stability. You can do the same thing with an ordinary laminate trimmer and a piloted flush-trim bit if you stand the router on the shelf edge. A trim router’s compact size makes it a safe choice for this balancing act. Just set the bit a tad deeper than the edging thickness and zip the overhang away. Quarter- or 1/2"-thick edging is a breeze, but I’ve even used mine to flush-trim thicker 3/4" lipping or to bring face frame edges flush with cabinet carcasses. Bits with a sheer cutting angle leave a cleaner cut, especially on hardwood.

freud trim router

#6 - Flush Cutting Plugs

Using a trim router with a straight bit can allow you to cut several thin flush cut plugs in a very short amount of time. On a recent project, I had 70-some wood plugs to trim flush. Of course, there are options to perform the job — flush-cut saw, multi-tool, chisel. But, I grabbed my trim router and a straight bit. If you use a thickness or two of office paper as a spacer for setting bit depth, you can shave plugs nearly flush in no time flat. Nibble them away with gentle, sweeping strokes. Follow up with a little sanding, and you’re done. I even trimmed plugs on my project’s vertical surfaces this way, thanks again to the tool’s small stature and light weight. I doubt I could have worked any faster with other tools.

man using trim router to cut joinery

#7 - Cutting Joinery

Trim routers will never take the place of true joinery cutters in most shops, but for small, quick joints, it works fairly well. A trim router isn’t a panacea for every routing operation, of course. Big bits and deep cuts spell trouble with a tiny router, so use common sense. Still, you can cut rabbets, dadoes, laps and other joint parts with a trim router, the same way you would with larger tools. Run the edge of the base against a clamped straightedge; install an edge guide or use a piloted bit to limit cutting depth. The key is to take reasonable cuts so you don’t overwhelm the motor or the bit. I used a trimmer to cut all of the back panel rabbets and shelf dadoes for a small cabinet to store cans of finish. The cuts turned out every bit as accurate and crisp as if I had made them with a dado blade or my mid-size router. Would I use a trim router for cutting joinery on every project? No. Three-quarter-inch through dovetails? Forget it. Nada on deep mortises, too. I would choose my bigger routers, router table or some other method for safety’s sake on tough jobs like these. But, some joinery can be cut with a trimmer. Give it a whirl.

using dewalt trim router to make a sign

#8 - Signmaking

Using a trim router and letter template guides, you can make a great sign in almost no time. Here’s a fun way to burn an hour or so of shop time: rout a sign. It’s easy to do with a set of letter templates and a trim router equipped with a template guide. At first blush, this technique would be improved with a plunge base, and most trim routers don’t have them. But, here’s how to get it done with a fixed base. Use a softwood for your sign stock. Position the bit over the widest part of each letter, and start here. Hold the router base firmly with one edge pressed against the template, and slowly pivot the machine down into the wood. Once the base is resting flat, you’re golden. Rout away!

using trim router to drill holes

#9 - Hole Drilling

Just like with your standard plunge router, you can bore shelf pin holes with your trim router and a template. The concept of using a plunge router for boring shelf-pin holes isn’t revolutionary. But, thanks to plunge models such as Trend’s T4, DeWALT and Porter-Cable, hole drilling is fair game for trim routers too. Make a shelf-pin template with holes sized to fit a guide collar bushing, and install 1/4" upcut spiral bit in the machine. A router works as well as a drill here, and perhaps even better. Maybe I’m just one of those guys who roots for the underdog, but I think it’s time for our trim routers to get more credit. Try these techniques with your trim router and see if you agree.

using ridgid trim router for mortising inlays

#10 - Mortising Inlays

Cutting thin, flush inlays requires small cuts and precision, which makes the trim router the perfect tool for this job. Inlays require a shallow excavation to seat them flush with the surrounding wood. You can get the job done with other routers too, but a trim router is my first choice. Its small size offers several advantages for precision work like this. Trimmers are much lighter weight than mid-size machines, so you can guide them right up to a knifed outline of your inlay with better control. I use a 1/8" or 1/4" straight or spiral bit. If you have a steady hand and a good eye, there’s no need for a template here; just guide the machine freehand. And, if you’re mortising a narrow apron or small box side, a trim router’s little footprint really helps. A few new machines, like RIDGID’s Model R2401, even have an LED light to brighten up the cutting area — and that’s a big bonus for this sort of exacting work.