The Editors Mailbox

The Editors Mailbox

How to Install Knife Hinges

comments (1) December 29th, 2010 in blogs

thumbs up 35 users recommend

Knife hinges arent all created equal. The hinges on the left and right are stamped steel with a riveted pivot pin, making them nearly impossible to install accurately. In the center is a Brusso hinge, well-machined and much easier to install. - CLICK TO ENLARGE

Knife hinges aren't all created equal. The hinges on the left and right are stamped steel with a riveted pivot pin, making them nearly impossible to install accurately. In the center is a Brusso hinge, well-machined and much easier to install.


1 | 2 | 3 > View all

Installing Knife Hinges
Learn Fine Woodworking contributing author Gary Rogowski's technique for super-solid knife hinge installation.

The straight knife hinge is used in situations where the top and bottom of the carcase extend over the door frame, and the door frame covers the carcase sides.

An L-shaped knife hinge, like the one seen here, is used on full inset doors. The short leg of the hinge, into which the pivot pin is set, moves the pivot away from the carcase so that the door can swing clear of the carcase side without binding.

Accurate Placement is Key to Success
Laying out the mortises for either type of knife hinge involves essentially the same steps. Layout is the most critical part of setting them. Installed correctly, knife hinges will hold a door true to the face of the carcase and establish a consistent reveal between the door and the carcase sides all the way around. The key to achieving both of these goals is accurate placement of the hinge leaves. This comes down to a precise hinge setback in both the carcase and door and shimming the door hinge against the carcase wall to set the reveal.

Hanging a door with knife hinges begins with making sure the dry-assembled carcase's face is flat and square. Before gluing up the carcase, lay out the two carcase hinge mortises, disassemble the carcase and then rout and pare the hinge mortises. Glue-up the carcase, and then let the glue dry, checking again to make sure the carcase is square across its opening. Plane or sand the face of the carcase flat.

For a consistent reveal around a door, use shims the same thickness as the hinge washer. Many varieties of plastic laminate are the right thickness, but cardboard and other materials will often work as well.
To lay out the hinge mortise, start with a pencil. With a laminate shim between the carcase wall and the hinge, the author marks the end of the hinge leaf and the edge of the short leg of the "L." These reference lines set limits for a marking gauge, which is used next.
Marking-gauge line establishes front edge of mortise. Scratch a marking-gauge line from pencil mark to pencil mark. The marking gauge should be set for the distance from the center of the pivot pin to the outside edge of the hinge leaf's long leg. Try not to let the gauge wander along any sloping grain.
Use a knife to mark edge and end of mortise. Position the hinge leaf on the marking-gauge line, mark the end of the hinge leaf and the inside edge of the "L" with a knife, and then erase the pencil lines.

1 | 2 | 3 > View all


posted in: blogs, how to, cabinet, hinges, installing hinges, knife hinge


Comments (1)

Dekester Dekester writes: Not sure if the author or anyone will be checking in, but can anyone offer trouble shooting advice and a little more guidance on installation? For example, are the pin hinges always in the frame/cabinet and the open/female pieces in the door? If pints start to jam or tighten, what might cause that?

Sorry for such rookie questions, but you'ld think $25 hinges would come with at least a little instructions! We aren't all seasoned pros... alas... :-)
Posted: 6:36 pm on August 22nd

You must be logged in to post comments. Log in.

Advertise here for as little as $50. Learn how

Save up to 52% on Fine Woodworking

 

Become a Better Woodworker

ABOUT THE EDITORS MAILBOX

FineWoodworking.com editors report from the woodworking front lines. Check in every weekday for news, information, projects, and answers to questions from Fine Woodworking readers everywhere.

Learn about our new format!

Archive: Temporarily unavailable. Stay tuned and sorry for the inconvenience.