Keeping vintage door hardware working

Quick answer

Old mortise locks can usually be cleaned, lubricated and adjusted rather than replaced. When parts are worn out, a new mortise lock can fit the same pocket, or a conversion kit can add a modern deadbolt without losing the look.

Many older San Gabriel homes, especially near the Mission District, still have original interior and front doors with mortise locks: a rectangular lock body set into a pocket in the door edge, with a knob, a skeleton keyhole, and sometimes a thumb latch. They are beautiful and solid, and they do wear out.

Common problems

• The knob spins without moving the latch
• The latch sticks in or out
• The key will not turn or the lock is missing its key
• The knob is loose on its spindle
• The door does not latch because the strike is out of line

What is inside

A mortise lock contains springs, levers and a latch bolt. After decades, old grease turns sticky, springs weaken, and set screws loosen.

Repair first

We remove the lock body, clean out old grease and grit, lubricate with a dry graphite or light lubricant, replace broken springs where parts exist, and reinstall. We adjust the strike plate so the latch catches cleanly.

When to replace

If the case is cracked or parts are unavailable, new mortise locks are made to fit standard pocket sizes. For front doors, we can also add a separate deadbolt or a mortise conversion that offers modern security.

Glass and porcelain knobs

Vintage glass knobs loosen on their spindles. New spindles and screws restore a tight fit.

Skeleton keys

Interior mortise locks in older homes often use simple skeleton keys. Replacement keys are easy to find by matching the lock. If you only need privacy, a key that fits most interior locks can be kept on a hook nearby.

Front-door mortise locks

Front-door mortise locks are larger and use cylinder keys. They are strong when in good condition. If the cylinder is worn or keys are missing, a new cylinder can usually be fitted to the old lock body.

Restoring finishes

Brass and bronze hardware can be cleaned to bring back its finish. We avoid harsh abrasives that remove the patina unless you want a bright look.

How a mortise lock works

A mortise lock sits in a deep rectangular pocket cut into the edge of the door, rather than in a round bore like a modern lock. One body holds both the latch and, often, a deadbolt operated by a key. Many San Gabriel homes from the 1920s through the 1940s still have them on interior and front doors, with glass or brass knobs, decorative escutcheon plates and skeleton keys. They are durable, but decades of use wear the springs, levers and keys.

Common problems

• The knob turns but the latch does not retract, usually a broken spring inside the lock body
• The knob is loose or falls off, usually a loose set screw on the spindle
• The key will not turn, because of worn wards, a different key or paint inside
• The latch does not catch, often because the door has sagged and the strike no longer lines up
• The door rattles, since the strike is too far from the stop

Opening the lock body

Our steps:

• Remove the knobs by loosening the set screw on one knob and pulling the spindle
• Remove the screws on the faceplate at the door edge
• Pull the lock body out of the mortise
• Open the case cover carefully, noting how springs sit
• Clean old grease, replace broken springs, and lightly lubricate with graphite or light grease
• Reassemble and test before reinstalling

Taking a photo of the inside before removing anything helps when putting it back together.

Parts and keys

Springs and some parts can be found from restoration hardware suppliers, salvage shops, and locksmiths who work with old locks. Skeleton keys are simple to duplicate. Original locks are not very secure on exterior doors; a modern deadbolt added above, or a mortise lock replacement designed for security, improves protection while keeping the look.

Glass knobs

Glass and crystal knobs loosen at the metal shank. Some can be reset with epoxy. Knobs with a spindle that has worn threads may need a new spindle. Matching replacements are often available from salvage sources.

Strike adjustments

Old doors sag. When the latch does not line up, the strike can be moved slightly, or the opening filed. Tightening hinge screws or adding long screws into the frame lifts the door back toward square.

See heavy plank doors and strap hinges.

Painted hardware

Many hinges and plates have been painted over. Removing hardware and soaking it in a slow cooker with water and a little dish soap softens paint so it peels off. Check for lead paint first.

Keeping original hardware

Original hardware is part of what makes an older San Gabriel home feel right. Even when a lock is worn out, the knobs, roses and escutcheons can often be kept and paired with a rebuilt or replacement lock body of the same size. Measure the faceplate height and width, the backset from the door edge to the spindle, and the distance between the spindle and keyhole before shopping, since those dimensions decide what fits the existing mortise.

What our visit involves

We go door by door, repair or replace locks and knobs, align strikes and plane any door that drags. See doors, cabinets and hardware.

After a hardware job near Las Tunas Drive, we like to stop at Newport Seafood, as long as it is not a Tuesday.

Want us to handle it?

Call or text (626) 684-3505, Mon–Sat 8:30 AM–7 PM. Send a photo and we will give you an upfront quote.

Call or text (626) 684-3505