Building Wide Glass Cabinet Doors

Advice on construction details and hinge choices for wide glass doors. July 10, 2007

I need to make two cabinet doors for an entertainment unit. The measurements for each door are 22" tall x 24 1/2 wide (inset). The panel calls for smoked glass. Do you foresee a problem at the joints? I don't feel comfortable building these doors. Could I eliminate the wood frame and just use a smoked glass door?

Forum Responses
(Furniture Making Forum)
From contributor K:
I would suggest making 2 doors at that width. In fact, most manufacturers won't even guarantee the door over 24" width. Also, the tolerances for inset doors is so small that the slightest sag will be very noticeable at the top. On that note, glass isn't the lightest panel. The glass-only door is a good idea, although I would still rather make it a pair to relax the load on the hinges. What kind of hinges would you use if you made them framed? If you use Blum inset, they will sag. I would suggest a mortise or non-mortise hinge. Something that doesn't have an arm on it. That may not work if the customer doesn't want to see the hinges, though. Sounds like you have your hands full. My suggestion is to ask the customer what they want it to look like, and then explain to them the pitfalls if they choose the worst option. Have them sign a waiver stating that the doors are not guaranteed.

From contributor V:
You could still use one door by splitting it down the middle with another stile. That won't solve the sag problem, but it would lend overall strength to the door itself.

From the original questioner:
The opening width is 49 1/2 and the customer wants the center to be open (free), so just 2 doors. I was going to use a Blum inset hinge, but you're probably right on the sagging (thanks). I'm going to sit back down with them, suggest the mortise hinge, and go from there. Maybe a bridle joint pinned would help the stability down the road.

From contributor V:
I guess I should have stated it differently. One door each side with 2 panes of glass in each door with an extra stile in the middle. Still keeping it free in the middle between the doors.

From contributor K:
I wouldn't worry as much about the joints failing if they are done properly. I would worry more about it twisting. It really stinks when the bottom sticks out past the frame and the top is less than flush and you can't adjust it out anymore. You'll especially have problems with this with mortise and non-mortise hinges because you can't adjust them in and out.

Is the 49 1/2 span supported from underneath or are you beefing it up somehow? I've seen a lot of cabinets sag and would suggest using a stile even if it is small. I'm guessing that this is the center section of the entertainment unit going either above or below the TV. It may not sag right away, but keep it in mind for the future. And if it is the section under the TV, even if the bottom is supported with sleepers doesn't mean the top won't sag. Just a thought. If anything, the mid stile (or mullion) would allow for a smaller door (i.e. a 2" stile would make the doors 23 1/2", not 24 1/2). This width would be guaranteed from a supplier.

From the original questioner:
I get what you're saying, contributor V (with a middle stile). And contributor K, you're right - I didn't think about not being able to adjust with a mortising style hinge, and now that concerns me. The bottom rail which wraps the front is a 4" piece. This is a corner unit. Great points, thanks.

From contributor P:
I'd have no qualms about doing this with mortised hinges. As for the lack of adjustment: if you build the case square, the opening square, and the door flat and square, and set the hinges correctly, you'll have no problems. You just have to level the case on site, something you would have to do in any case. In my experience hinges which can be adjusted tend to un-adjust themselves pretty quick.

From contributor J:
You could use "smoke Acrylic" instead of glass. Way lighter, almost no strain on hinges. Or you can also go with no frame and the slide in glass hinges with a 9mm pin and bushing. Works great.

From contributor N:
Acrylic is absolutely lighter than glass by far. However, the customer needs to be cautioned about cleaning. Even paper towels and Windex will quickly leave scratches behind. Weekly or even monthly cleanings (unless plastic cleaner/polish is used) will start to fog the acrylic in under a year. I wouldn't want the callback from the customer who hated the appearance of his/her smoked doors that soon.

Doors built with mortise and tenon joints, rather than cope and stick, will support the weight of the glass easily, and the glass will nearly eliminate the risk of a callback.

From contributor V:
If you got cunning to avoid the sag, perhaps a couple of 'closing blocks' at the bottom of the doors that lift and locate the doors into the exact closed position. The self-closing hinges would lend themselves well to this method.

From the original questioner:
Thanks for the responses! Very informative.