Converting Cabinet Doors to Glass Doors

It is a fairly common scenario. You want to add a glass door to your existing

kitchen cabinets. The manufacturer of the cabinets doesn’t make that style or color anymore and even if they do, a factory fresh door will not match one that has aged in the light for a few years. So, is it possible to convert the existing door into a glass door? In most cases, the answer is yes.

The main thing to determine is how your doors are put together. Though it is possible to convert composite material doors like PVC and melamine, this article is going to focus only on wood doors. Some wood doors are simply a sheet of plywood with a design routed into them and this is a different animal as well. Most doors are composed of a stick built outer frame with some type of a panel in the center. This is what we will be concentrating on.

I have seen methods of doing this with a router, spiral saw, rotary tool and some others, but the setup for these can get extensive and if the jig slips the consequences can quickly get really bad. In recent years oscillating multi-tools have become popular and reasonably priced. This is the method we are going to use. If you don’t own one of these, a decent corded oscillating multi-tool can now be had for under $100 and considering the cost of the alternatives to attain a glass door, this is not at all an unreasonable job cost. Besides, when you are done, you will still have a really cool tool for other projects. (Hint, hint – great excuse to buy cool new toy)

I have no incentive to plug oscillating multi-tools so allow me to explain why I choose this method. It is quick and does not require a lot of set up. It is manageable for fine work like this. Mistakes or inaccuracies with this tool are usually small and repairable as compared to something like a router that can take off and cut a big gouge before you know what happened. With a little practice, you can get very accurate with this saw. In the sphere of woodworking power tools, this is like a surgical instrument.

Now in the same breath that I am not suggesting this is quick and easy, I am also going to emphasize that the key is to take your time. The greatest drawback to this project is that if you mess up, you have just potentially ruined the only door that is an exact match to your kitchen. So, let me say it again, T A K E Y O U R T I M E. Be patient and precise. If this is your first time using a method like this, practice depth cuts and long straight cuts on a scrap piece of the same species of wood to get the feel for it.

Now that you should be questioning the sanity of this endeavor, let’s overcome fear with knowledge. The center panel of a solid door is captured within a mortise in the frame. A glass door is not, typically, captured within a mortise. It is set into a dado and secured either with glass clips or silicone. (Fig. 1) So to prepare for a glass door, we are going to remove part of the mortise to create a dado and eliminate the center panel.

Determine the depth of the mortise. This can be measured either on the top or the bottom of most doors. (fig. 2) If you happen to have a door where the door is mitered at a 45° like a picture frame, you may have to do a little exploratory surgery. Pick a spot on the back of the door and cut back ¼”. If you do not find the edge of the insert panel, continue removing in 1/8” increments until you do.

On the back of the door, mark the depth with masking tape to determine the line you want to cut. I recommend putting some cardboard down to prevent the possibility of scratching the face of the door. Clamp a straight edge to the back of the door along the line you want to cut. This will serve as a guide. (fig. 3)

Slowly and carefully, cut the line to the same depth as the reveal between the back of the door and the insert panel. You can put masking tape on the blade as a depth guide if you want. Be sure to look for small 23 gauge pin nails as you are cutting. Many manufactures use these to stabilize raised veneer or flat panel inserts. The frame and the insert can expand and contract at different rates sometimes splitting the seams of the frame or exposing unfinished wood on the insert panel. On solid wood doors, there are often rubber bushings between the edge of the panel and the crotch of the mortise. (fig. 4)

If you have an arched or cathedral top door like the one shown, a curved cut is required for that section. Mark the approximate line with tape being careful that you are not going to cut too far back into the door. Make a rough cut with the oscillating multi-tool and clean it up with a good sharp chisel. (fig. 5)

At this point, the panel should pop out. If you are getting any resistance, and all the edges are clearing the frame, you may want to flip the door over so the front is facing you. Using a very sharp razor knife, gently and carefully run it along the seam where the insert panel meets the frame. There is a possibility that finish is causing the panel to stick and by scoring that seam, you will protect the front of the door from possible chipping.

Once you have the center panel out, use a stain that matches closely or even one of those touches up stain pens to treat the raw edge. You will see very little of it, even when the door is open, but a raw edge has a tendency to stick out.

Drop in your glass. This can be attained from a local glass shop or even the big box home improvement store.

You can use glass clips to secure the glass or silicone. I prefer silicone because it rattles less. However, the glass clips are easier and you don’t have to wait for it to set.

At this point your door is done, mount it back on the cabinet and enjoy the view.