Repair Damaged Hidden Hinge to Last FOREVER!

My wife and I renovated our kitchen several years ago with high quality hardwood faced cabinets and mounting hardware. Imaging our chagrin when the hidden hinges on our carousel cabinet started to give way after only 3 years. The hardwood frame was under a lot of stress due to the brittle nature of the wood itself, very short screws to mount the hinges, and the weight and torque the fully opened doors put on the frame. I attempted “half fast” repairs, but these failed as well.

I had the tools below already. Those I needed to get specifically for this project are indicated in the appropriate step.

Screwdriver. Hammer, Center Punch & Chisel. Shims and block. Masking tape and marking tools. Protective gloves and eyewear. Workbench and vices/clamps. Measuring tools. Exacto/Utility knife. Drill and bits. 80 grit sanddpaper.

I removed the door, and removed the mounting hinges. These hinges are very conveniently disassembled, but this repair can work for all hidden hinge types. I took the hinge to the hardware store to determine the best “T” mounting plate and screws. I got the appropriate tap and drill set for the screws. I also picked up a fiberglass repair kit. Be sure cloth is included in the kit. I already had a tap handle of the correct size, but get one if you don't have one.

Look ahead to step 5 to estimate the length of general purpose screws needed to attach the "T" place to the existing cabinet frame(s). Return here with the estimate you made. The ones pictured above, I had already

On the workbench, align the frame leaf to the “T” plate, and mark. Center punch, drill and tap the threads in the “T” plate. Deburr the newly tapped threads with a wire brush or similar. Test fit the frame leaf to the “T” plate. Measure the runout of the screw from the front surface of of the “T” plate.

Re-attach the hinge to the door. Place masking tape on the door so that it can be seen on the side stile of the door, as well as the back. Place a mark for the edges of the “T” plate, and the newly tapped screws.

Fit the door back into position and shim to correct position. Don’t attach the hinge to the cabinet frame yet. Place masking tape on the cabinet door frame. And transfer the marks from the tape on the cabinet door. Set the door aside.

A relief cut will be made in the cabinet frame to account for the thickness of the “T” plate. I used an Xacto blade to remove just enough masking tape ti indicate desired depth.

With a spiral saw, chisel, or similar tool, remove the damaged wood. Don’t go too deep (the runout measurement was made above in Step 2.)

Use chisels to pare the relief cut to the depth needed.

Measure for the desired length of screw. The length of screw I chose went well into the frame of the adjoining cabinet. I happened to have an appropriate length of screw on my shelf.

Make pilot holes, and attach the “T” plate with appropriate length screw. Mount the frame leaf to the “T” plate with the machine screws, then affix the door to check for rough fit. Use the shims to adjust to the tape marks on the frame and door. Adjust the depth of the relief cut in the cabinet frame if necessary. Remove the door and set aside.

Rough up the surfaces of the inside of the cabinet and the exposed surface of the “T” plate. Measure the size of the fiberglass cloth needed and cut it out. Mix the epoxy according to the fiberglass repair kit directions, wet the roughened cabinet and “T” plate surfaces. Lay on the fiberglass cloth patch. work more epoxy into the cloth to wet it, and force epoxy into the factory holes of the “T” plate. When the epoxy is cured, pilot and insert short screw only in the indicated hole.

Re-install the hinge’s frame leaf and door leaf. Use shims to align to door to its correct location, and make adjustments to the hinges to ensure plumb, swing, level, and clearance. Remove the tape, and enjoy the adoring look from your spouse!