Make a Wood and Brass Panel Gauge
By: Bob Rozaieski
Learn how to work with brass and make an indispensable tool for hand work.
If you rip your stock on a table saw, your uses for a panel gauge are limited. If you make your rip cuts with a band saw or hand saw, however, a panel gauge is an indispensable tool. Its usefulness really shines when you need to mark out multiple wide panels to the same width such as the sides of a carcass or the shelves of a bookcase. You can use a ruler and straightedge to perform this task, but the panel gauge is more efficient and precise.
Panel Gauge Requirements
I built a simple panel gauge 10 years ago. But after years of use, my old, poorly designed gauge is starting to get a bit worn and loose, affecting its precision and usability. I considered buying a new one, but there are few commercial options available and each has at least one shortcoming that I wasn’t willing to accept. So I decided to build one.
My new panel gauge needed to meet several requirements. First, the beam should be at least 28″ long to allow marking out case sides up to 24″ deep. Second, the beam must lock in place rigidly with no movement whatsoever. Third, the fence has to register solidly on the stock. Finally, the gauge must be able to mark both rough sawn and milled lumber, which means it has to accommodate both a knife and a pencil.
This panel gauge also incorporates brass for the locking mechanisms and wear parts. Brass can be cut easily with a hacksaw and shaped with files. Tapping brass is also straightforward. Plus, it polishes it up nicely.
Start with the Fence
I’m using 11⁄4” thick hard maple for my gauge because it’s a dense wood that will be resistant to wear yet it can still be worked easily enough with hand tools. However, any heavy, dense hardwood will work just fine.
Mill the stock for the fence to dimension, then bore the holes for the beam mortise and 1⁄2” brass nut. The beam is pentagon-shaped so that will lock down without any wiggle at all. In order to layout the mortise for this shape, start with a diamond by drawing lines tangent to the hole at 45 degrees to the bottom of the fence.
After laying out the 3⁄4” diamond mortise, chop the sides with a 3⁄4” chisel. Work half way through the stock from either side, meeting your cuts in the center. The resulting mortise should be as clean and straight as possible so that the fence slides easily on the beam without being loose and sloppy.
After chopping the diamond, lay out the 1⁄4” square mortise for the brass pressure foot on each face of the fence. To do this, measure 1⁄8” above and below the top point of the diamond (the center of the mortise) and draw lines parallel to the bottom of the fence. Similarly, measure 1⁄8” left and right of the top point of the diamond and draw lines perpendicular to the bottom of the fence. Chop out this mortise to a depth of approximately 1⁄8“.
This will leave you with a section in the center that is still “V” shaped. Pare away the “V” shaped material just to the tip of the diamond. You will end up with a mortise that is 1⁄4” wide x 1⁄4“high x 1⁄8” deep on each face, connected by a mortise that is 1⁄4” wide x 1⁄8” high and about 1″ deep through the center.
Complete the Brass Work
The nut for the thumbscrew is made from a short section of 1⁄2” round brass rod. In order to ensure that the hole in the wooden fence stock lines up with the hole in the 1⁄2” round brass nut, bore through both at the same time. Use a bit sized for the thumbscrew you are using (mine is 1⁄4“-20 TPI).
Bore straight through the brass all the way into the beam mortise (a drill press makes this step easy). Then, remove the 1⁄2” round brass stock and bore the hole in the fence larger to create clearance for the thumbscrew. Tap the hole in the 1⁄2” round brass stock to match the threads of your thumbscrew, and cut the brass stock slightly oversized with a hacksaw.
Make a 1⁄2” by 1⁄2” rabbet in the bottom corner of the fence to provide better registration of the fence on the stock being marked. Since the rabbet is subject to significant wear, attach a pair of 1⁄8” thick x 1⁄2” wide brass strips with 30-minute epoxy. These wear strips will help to lengthen the life of the fence. Leave them slightly oversized for now.
While you have the epoxy mixed, glue in the brass nut if you’d like (this step is optional but makes the gauge more user-friendly). To do so, insert it most of the way into the hole and add a bit of epoxy to the two ends before setting it all the way in. This will keep epoxy out of the threads. Make sure to get the thumbscrew hole aligned and the thumbscrew functioning before the epoxy sets up.
Now turn your attention to the pressure foot. This small brass foot is cut and filed to shape from a 1⁄4” x 1⁄4” x 11⁄2” piece of bar stock and applies pressure to the top of the beam to lock it in place. Without this piece, the thumbscrew would damage the top surface of the wood beam.
Once the epoxy has cured, all of the brass can be filed flush with the faces of the wooden fence. To hold the pressure foot in place for filing, wedge a small piece of soft pine in the beam mortise.
Make the Beam
The beam starts out as a 3⁄4” square piece of maple. Plane the corners off the beam leaving a small flat. To create the larger flat surface for the pressure foot to contact, plane the top corner down until the flat is about 1⁄4” wide.
Bore a hole to fit a pencil about 3⁄4” from one end. Make a vertical saw kerf through the end of the beam, through the center of the hole and about 3⁄4” past the hole. In front of the pencil hole, bore a horizontal clearance hole for a wood screw on one side of the kerf, and a pilot hole on the other side of the kerf. By putting a wood screw in this hole, you can pull the kerf closed to clamp a pencil in the beam.
Fit the Knife
On the opposite end of the beam, chisel a 1⁄2” wide x 3⁄16” deep notch. Cut a piece of the 1⁄8” x 1⁄2” brass stock and fit it to the notch. Bore and tap a hole in the center of the brass for a #10-32 machine screw. Bore a shallow relief hole in the beam behind the brass so that the screw does not press into the wooden beam, and then epoxy the tapped brass strip into the notch. Once the epoxy has cured, file the brass flush with the beam.
You have several options for the knife. The easiest is to purchase a panel gauge knife (Lie-Nielsen carries them). If you go this route, you may need to alter the size of the mortise at the end of the beam to fit the knife.
I made a knife from an old card scraper. To do so, cut a 1⁄2” wide strip from the edge of the scraper. I used an abrasive cutoff wheel in a rotary tool. You could also clamp the scraper stock between two scraps of wood and use a hacksaw to cut through the wood and scraper at the same time.
File the cut edge until the blade fits into the notch in the end of the beam. Grind a curved cutting edge and bevel on one end of the knife. Drill a series of holes down the center that will become a slot for the mounting screw. Use a chainsaw file to connect the holes and smooth out the slot. Cut the knife to length, file the edges to remove the sharp corners, and polish the faces on a honing stone. You can then hone or file the bevel.
Finish is Optional
I go back and forth when it comes to finishing tools. On the one hand, applying a couple of thin coats of finish will protect the tool from dirt and keep it looking pretty longer. On the other hand, any film finish is going to wear away with regular use. For this gauge, I applied a couple of coats of an oil/varnish blend, lightly sanding with 600 grit sandpaper between coats. I don’t know how long the finish will last. But I have no doubt that this new gauge will last me at least the rest of my lifetime. PWM
For more from Bob Rozaieski, visit his personal blog at brfinewoodworking.com
This article appeared in the August 2018 issue of Popular Woodworking Magazine.
Instead of making great furniture with minimal tools, this time Chad’s showing how to make three shop tools that will see use every day: a wooden mallet with wrapped handle; a marking gauge and a square that can be checked and adjusted for accuracy.