Have you ever completed a cabinet carcass glue up, only to find you didn't perfectly align the web or dust frames in their dados? Now there are small gaps or protrusions where the face frame and back need to go. That'll never do. The gaps will cause weakness in the cabinet, and the protrusions won't allow the face frame and back panels to be attached properly.
Don't tear down the cabinet and start over! This Instructable will detail the process behind repairing gaps and protrusions so the final glue up to the remaining sides goes perfectly, and your cabinet is strong.
You will need:
- Additional material that you made the web frames from; I used pine 1x4s
- Brad/pin nails
- Blue tape
- Tape measure
- Table saw
- Feather board (optional)
- Miter saw or crosscut sled
- Flush trim router bit
- Lots of clamps - bar/pipe, spring/grip, QuickGrip/F-Style
- Silicon glue brush
- Brad/pin nail gun
- Vise Grip/locking pliers
- Palm sander
Step 1: Cut Repair Strips
I used pine 1x4's for the web frames, which the real dimensions are 3/4" x 3 1/2". So naturally I used the same material to repair the web frames.
I doubt this method of gluing on a strip and trimming it down would work well for plywood or MDF. If you used plywood for your web frames, use solid wood to shim it. Don't use MDF for web frames, MDF isn't very strong and can split really easily.
If I ripped a 3/4" strip, I could get 4 of them from one 1x4. I planned to just rip them holding them against the fence with push sticks, but decided to add a feather board to my miter track to ensure no kick back on my table saw.
Next time, I would use 1/4" strips, because my gaps were small and I had to take off lots of excess material.
Step 2: Glue & Clamp Repair Strip
Gather all your materials. A glue up is most successful when everything is ready and in place.
For the glue up, you will also need:
- Several tape strips
- Quick grip style bar clamps
- Long bar/pipe style clamps
- 2 inch grip/spring clamps
- wood glue (I prefer Titebond II for indoor projects)
- Silicone glue brush
Start with a dry run. Fit the pieces on the web frame fronts and clamp them on. Ensure a tight fit. If the dry run goes well, unclamp the dry piece and apply glue. Wipe a consistent spread of glue across the whole joint with the silicone brush.
While holding the glued end to the web frame, apply tape as tight as you can one handed to one side. Then apply tape to the other side as tight as you can. Then fill in the middle sections with tape, pulling as tight as you can before sticking the tape down. The tape is just to get the joint started, the clamps will apply the real pressure.
Apply a 2 inch grip clamp to each end to make sure the joint is aligned vertically. Then add bar clamps across the joint all along it to ensure a tight bond. You know you have tightened the clamps properly if you see some good glue squeeze out. You don't want to crank it down too hard, but enough to form a solid bond across the whole joint.
Wait 24 hours to remove the clamps. I know, glue sets up in an hour; I still prefer to let the joint cure fully until disturbing it.
Remove the tape and clean off the squeeze out. Whatever won't scrape off with a chisel lightly you can hit with a detail or palm sander.
Step 3: Trim Off the Excess to a True Edge
To true up the edge, I'm going to attach a temporary fence on the web frame where it meets the face of the cabinet, then use a flush trim bit in my router to trim most of the material away. Then for the edges, I'll hit it with a chisel and sanding to get it flush.
For the fence, use one of the extra strips cut from the 1x4. It can be attached with carpet tape, pin nail it on, with hot glue, or a few drops of cyanoacrylate glue (super glue). If you use carpet tape or glue you'll need to pry it off with a paint scraper or chisel. If you use pin nails, you can use a pry bar.
Once the fence is attached, chuck a flush trim bit into your router, and set it so the depth of the bearing hits the fence. Always adjust your router or any tool with the power cord unplugged.
Ride the router along the face, bearing hitting the fence and flush trim as much material as possible. Scribe a line at the edge of the fence for the remaining wood. Then, remove the temporary fence.
To chisel away the excess, make relief cuts across the grain and then follow the grain taking off a small layer at a time. Stop when you are 1/16 to 1/8 inch proud of the line, and then switch to a sander, and sand to the line. Keep the sander square against the face.
You could probably also remove the excess with a block plane if you have one.
Step 4: Attach the Face Frame & Back Panel
Now that the front edge is trued up, you can attach the face frame. You may need to apply some force to square up the cabinet. You should repeat the previous steps if you have large gaps in the back of the cabinet, or if the web frames are proud of the rabbet to hold your cabinet back panel.
With the edges of the web frames true to the face of the cabinet, your glue up will go more successfully, and your cabinet will be stronger. It may not be perfectly square, but when adding the back panel and face frame it can help square it up enough. You're not building a piano, so a little bit of slop in your tolerances can be okay. Unless you are building a piano.