Shop-Made Coping Sled

A Must-Have Easy to Build Jig

If you make cope and stick frame and panel doors or rout the end grain of narrow boards for any reason, you need this jig. It supports a narrow workpiece, 90-degrees to your router table fence, so you can safely guide the sled across the router table with your hands positioned on the sled handles--well away from the router bit.

Shop-Made Coping Sled Plan and Cutting List - download the following PDF for coping sled plans, including an exploded view of the sled, a cut list, and source list for all of the products used in the sled.

Here's how it works

Set up your router table with a coping bit. Set your workpiece in the sled against the support backer (M), so the business end protrudes approximately 7/8" on the polycarbonate guide side.  Slide the front clamp mount--tight against the workpiece and tighten

its wing nuts. Lock down the 3 lever clamps. Set the sled guide against the router table fence.  Raise the bit height to cut the proper cope. Align the router table fence so it's in line with the router bit's bearing. Hold the sled tight to the fence, loosen the lever clamps, reposition the workpiece--so it is tight to the fence at the same time the guide is tight to the fence. Now you're ready to make the cope cut.

Making and using the sled is fun and easy. It will take you the better part of a day to build.You can build the top of the line model like I made for about $150, or make a simpler version without all the bells and whistles, for about $90. I'll explain more about that later.

I designed my sled based on one made by Infinity Cutting Tools, which I recently used and really liked. I gave mine a bit more capacity and made it slightly larger overall. Unlike most other designs which are guided only by the edge of the narrow workpiece, or worse yet, on a sacrificial edge of the jig, this one is guided by a 15" long piece of polycarbonate plastic. It's the key to making the routing easy and accurate.

Design Notes

This sled can hold a workpiece up to 6" wide and 1-1/4" thick. The polycarbonate guide (N) positions the jig parallel and 7/8" away from the router table fence. It's rare that you would be routing deeper than 1/2", so this should be plenty. The guide rides 3-3/8" up off the table. Make sure your router table fence is solid at that level. If it's not, adjust the length of the guide supports (C).

When using the jig, you can add a sacrificial backer board behind the workpiece to eliminate blow out at the end of the routed cut. I solve this a different way by cutting my rails wide at first, routing the coped ends, and then cutting off both edges at the same time I'm cutting the final width, eliminating blow out.

The anti-slip grit tape I used on the top of the base is a hardware store item.  You can get it from Amazon.com, too (see Sources). One last note: Don't be confused by the 12" x 12" size for the polycarbonate plastic shown in the Sources list. You can cut your 15" long piece from that piece if you cut it out on the diagonal. You may also want to check with your local plastic supplier and see if they sell scraps.

Cost Considerations

I figured I would use my sled for the rest of my life, so I went all out and spared no detail. I added a lot of "luxuries" which significantly increased the cost. I used UHMW Plastic Jig Stock for the clamp mounts and support backer (K-M). It's nice stuff, but maple is a worthy alternative. I used Nylo-Tape on the underside of the jig base for a smooth ride and large lever clamp feet for more grip, but those could go, too. I also bought a pair of silicone hand grips (only one is needed) from my neighborhood bicycle store for $10, but I can't find them for less than $25 on the internet. An uncovered rear handle bar dowel (J), a turned handle, or pipe wrap are options. Removing those four items would save you $60.

Make the Base

Cut the base pieces (A and B) 1/4" over-sized in length and width and glue them together (photo 1). Trim the assembled base to its finished size and make sure it's square.

Rout the T-bolt slots (photo 2). I found it safer to cut those halfway through from each face. To get the groove cuts started, you'll need to go forward and backward a 1/2" or so until the bit is plunged into the base.

Lay out, countersink, and drill the screw holes in the base.This is done on the underside. Use the screw hole layout drawing included in the PDF at the beginning of the article. Make sure the countersinks are deep enough so the screw heads are just slightly below the surface of the laminate.

Photo 1. Glue and clamp the plastic laminate to the 1/4" thick MDF. Use yellow glue, and side-to-side clamps to align the edges. The "sandwich" from bottom is: 3/4" particle board, wax paper, plastic laminate, wax paper, 3/4" particle board. The particle board distributes the clamp pressure.	Photo 2. Rout the T-bolt slots in the base. Stops on the router table fence control the start and end locations. Do the 1/2" wide shallow grooves for the T-bolt heads first, then do the 1/4" wide through slots.

Photo 3. Rout the 1/4" wide x 1/4" deep loose tenon grooves in the ends of the front cross support (E). Clamp the workpiece to a large block of scrap wood for support.

Make the Handle and Guide Supports

Rout the loose tenon grooves (photo 3). Routing these grooves can be a bit dicey. If you try to rout the full 1/4" deep right off the bat, the bit will grab the wood aggressively at the start of the cut.  That can be quite nerve racking. The solution I found was to make the groove cuts in several passes, slowly increasing the height of the bit.  Much less grabbing that way. Also, for the grooves in pieces C, D, and one of F, rout those in long stock first, then cut the pieces to their finished lengths.

Cut the 30-degree top of the front handle support (D). Drill the front handle mounting hole (photo 4). Threading the handle stud directly into the maple works great. I tried using a threaded insert, but man, that was a ton of work. This way is simple and just as good. Apply screw wax to the handle stud threads and drive it in the hole. Then remove it. Round the top outside corner of the front handle support. Glue the front guide support, loose tenons (G), front cross support, and front handle support together.

Drill the rear handle bar holes in the rear handle supports (F) (photo 5). Then from the other side, drill the screw countersink and clearance holes for the rear handle bar (J) screws. Round the ends of the rear handle supports.  Glue the rear guide support, loose tenon (H), and inside rear handle bar support together. Finish sand and apply clear finish to the front and rear handle assemblies. Cut the rear handle bar to length, add the cushion grip, and screw the handle bar to the rear handle bar supports.

Photo 4. Drill a 9/34" dia. x 5/8" deep hole for the front handle in the top end of the front handle support (D). Drill it perpendicular to the 30 degree top, centered in the width, and 7/16" in from the inside edge.	Photo 5. Drill the rear handle bar holes in the rear handle supports (F) using a 5/8" dia. Forstner bit. Drill holes 3/8" deep. Make sure to drill on the inside of the rear handle support that has the loose tenon groove.

Photo 6. Align the rear handle assembly to the base. Clamp a temporary square support block to the handle assembly inside. Align the parts, clamp it together, flip it over, and drill the screw pilot holes.

Photo 7. Screw the guide (N) to the guide supports. Align the parts using a 7/8" thick spacer set between the sled and router table fence.

Assemble the Jig

Align and clamp the front handle assembly to the base, then drill the screw pilot holes and insert the screws. Make sure the front handle support is on the correct side. I goofed this my first time!  Now do the rear handle assembly (photo 6). Its alignment is: The outside rear handle support is flush with the base outside edge and 1" in from the base rear edge at the corner. The rear guide support is aligned flush with the base rear edge.  The inside edge of the front guide support is set by the overall length of the rear handle assembly. It lands where it will and that should be darn close to 1/16" away from the base inside edge.

Cut the front and rear clamp mounts and the support backer to size (K, L and M). Drill the T-bolt holes in the front clamp mount (K).  Assemble the rear clamp mount and support backer (L and M).  Attach the lever clamps to the clamp mounts. The rear inside lever clamp is set at 10-degrees to the base so its foot is closer to the inside edge of the base. Align and clamp the rear clamp mount assembly to the baseCheck that the support backer is perfectly square with the inside edge of the base.

Apply the anti-slip safety grit tape to the top of the base and the Nylo-Tape to the underside.  Attach the front clamp mount to the base using the T-bolts and Ergostyle wing nuts.  Make and attach the polycarbonate guide (N) (photo 7).  Give the sled a test run. You can shim behind the support backer now or in the future, to adjust it--should it become out of square with the base.

I designed my sled based on one made by Infinity Cutting Tools which I recently used and really liked.

The following cut list and source list can be found in the PDF located at the beginning of this article.