hinging tempered glass

BobB · Post by **BobB** » Tue Nov 04, 2003 6:11 pm

I have a project that involves connecting 2 large pieces of tempered glass.

The first sheet is 1/4 inch thick, 4 feet x 8 feet tempered glass that I want to hinge a second piece of 1/4 inch thick, 2 feet x 8 feet tempered glass to it.

What would be the best way to do that? I thought about drilling the glass and screwing hinges to both pieces, with a rubber insulator between the glass and metal hinges, but am worried about the strength of the glass around the hinges.

Any suggestions would be appreciated.

Thanks,
BobB

Tony Serviente · Post by **Tony Serviente** » Tue Nov 04, 2003 6:38 pm

Bob-If the glass is already tempered you can't drill it. If you are going to drill and then have it tempered you'll probably have to search for a tempering plant that will work with you on that. If you get that far, go to a window glass shop that can give you advice. Your idea is pretty close to how it is done, but there are catalogs of hardward made just for hinging float. With sheets that big you don't want to take chances.

BobB · Post by **BobB** » Tue Nov 04, 2003 7:14 pm

Yes it's already tempered Tony. I need to attach the smaller piece securely and have the "connection" moveable and strong enough to support the weight of that smaller piece.

Back to the drawing board.
BobB

Paul Housberg · Post by **Paul Housberg** » Tue Nov 04, 2003 7:41 pm

CR Laurence supplies hinges that clamp to the glass with nylon screws, but depending on the weight, how the glass is supported and how it is used, they may not be adequate. Frameless doors, railings, etc. are frequently made with glass that is drilled and then tempered and they are surprisingly strong. But, that won't work in your situation.

Dean Hubbard · Post by **Dean Hubbard** » Wed Nov 05, 2003 12:22 am

Bob B,

I don't know the specifics of your project, all I know is the glass is already tempered and you want to hinge a small peice to a larger fixed piece right? I assume that this hinge is single acting and not double acting. (swing in both directions)

Something you can do besides using a clamp type hinge or a framed piano style hinge would be to make a full length hinge made out of only silicone. You will also need a few strips of tape, a straight edge, two fingers, glass cleaner and a few razor blades. Before you start, be sure glass is clean, at least where the silicone hinge is to be placed.

1. Lay larger piece flat on a cutting table or floor if needed with one piece of tape attached to underside surface along the edge where hinge is needed, with at least half the width of strip of tape exposed. You can also do this in a vertical situation, just be sure nothing moves.
2. Carefully set the smaller piece onto the tape leaving a small uniform space between both pieces. (this space determines how far the hinge will easily swing, the penetraction of silicone into this space is key, more penetration equals less swing/more strength, less penetration equals more swing/less strength) I use setting blocks to get uniform spacing.
3. Lay down the other two strips of tape on top surface of each piece of glass about 3/8" away from the edge of where hinge is needed.
4. Using a caulking gun, apply a generous amount of silicone, making sure you are filling the void between the glass.
5. Place straight edge near and paralell to one of the two strips of tape.
6. Place thumb alongside straight edge and place two fingertips into silicone so that the space between the fingers is directly above the joint.
7. Lock hand in position and pull along the entire length of glass.
8. Excess silicone should not extend or smear past the width of the tape. (Makes clean up a snap)
9. Wipe that blob of stuff off of your hands!
10. Don't move glass or try to remove tape until silicone is set up.
11. A cross section of the silicone hinge should look like a "T" with the top surface of the "T" being tapered up from the tape line to a peak right above the joint.

This is a surprisingly strong hinge. I would recomend that you do a small test first to get the hang of it and determine how far you need to space the glass. Also, if you are sure that the silicone has totally covered the space between the two strips of tape after gunning, spray some glass cleaner on it and your fingers prior to tooling with your fingers. I have used this hinge for many things and have never had a problem. Try it if it suits your needs. A good construction type silicone is what I would recomend, just make sure the glass is clean prior to application.
Good Luck!

Tony Serviente · Post by **Tony Serviente** » Wed Nov 05, 2003 10:14 am

Glazinguy-Is this a common practice in the glazing industry? I never heard of it before, but sounds like it a good technique to have available. I can imagine some smaller scale applications that I'll try it on. How about long term durability? What I'm wondering about is the glass to silicone bond, especially along the top of the hinge. Typically, how much angle of swing can you get out of this type of hinge? Can you get close to a conventional hinges range?

BobB · Post by **BobB** » Wed Nov 05, 2003 10:39 am

Tony this technique sound similiar to aquariums without the hinging part. You'll see a silicone looking seal on the glass to glass connections. I do wonder about the strenghth. The smaller sheet of glass weighs at least 20 to 30 lbs and it would be suspended or hanging from the larger piece only supported by the hinge.

The clamp on hinges may be a possibility.

BobB

Tony Serviente · Post by **Tony Serviente** » Wed Nov 05, 2003 11:02 am

Hi Bob-I've seen the joints on aquariums, and also on right angle corners in commercial installations and racquetball courts, but yeah, putting movement into the mix is what I haven't seen. I'm really curious as to how common and for how long this technique has been around.

Dean Hubbard · Post by **Dean Hubbard** » Wed Nov 05, 2003 12:13 pm

Your smaller piece is gong to weigh at least 50lbs. I wouldn't say this is a standard practice in the industry, unless you are talking about aquarium tops. You are not going to get a whole lot of swing as compared to a conventional hinge and this type of hinge is always going to want to be in the closed position. I suggested this application because you have limited choices at hand because you already have the tempered glass. This application would not be my first choice. If you need a hinge that stays in an open position, or need somewhere around a 90 degree swing, I wouldn't consider this type of application. Again, I stated earlier that I didn't know the specifics of your project. I don't see a problem with the ability of the silicone to hold the weight of the glass. You could also use a setting block on the bottom of the glass at the strike side for added support when the door is in the closed position, if the abilility of the silicone is in question.
If this project is for commercial use, or if the hinge is going to see excessive use, I would use a frameless shower door hinge. (My first choice would be a hinge like this, http://www.crlaurence.com/ProductPages/ ... 35&Origin=) CRL has an extensive selection of these types oh hinges available in different configurations. These types of hinges reqiure cut-outs, notches and or holes in the glass. (Which means you would need to re-order the glass.) A piano type hinge is also available, but that would require the use of u-channels applied to the glass. (Do you have the extra clearance in the width for this application?)
The hinge mentioned in an earlier post, is for showcase and stereo cabinet applications. If you are considering the use of that type of hinge, I would check with the supplier to find out the maximum weight support loads.
Another type of showcase/display cabinet hinge that you might want to consider, is configured with a short u-channel that attaches to the glass on the top and bottom edges. The u-channel is held in place with the use of two metal set screws that push against a flat metal insert bar between the glass and the u-channel. The u-channel has a small dowel pin that fits into a nylon sleeved collar insert. You would need to drill a hole in the header and the base for the nylon collar. The door glass in this application requires some allowance at the top and bottom, for the space that the u-channel and the lip of the nylon collar takes up. If you have enough clearance, top and botom, this would be a good way to go with this, because the weight of the door is setting on the bottom pivot point, the top pivot point keeps the glass door from tipping. (Again, I dont know if you have already commited yourself with the size of your glass.)

Dean Hubbard · Post by **Dean Hubbard** » Wed Nov 05, 2003 6:21 pm

Bob,
I did some checking for you on that last hinge I described. It is designed for 3/16". (I posted a link for you below.) The size of your glass also exceeds the reccomendations. You might be able to eliminate the set screws/insert plate and silicone or urethane the hinge onto the glass. Other than re-ordering the glass, this might be your only option, other than attaching a piano hinge to two u-channels. I also checked on the other hinges with plastic set screws that don't require holes. I was told that your glass size also exceeded the limits of those hinges as well. You should be able to design a workable hinge for the 1/4" glass based from this design: http://www.crlaurence.com/ProductPages/ ... 11&Origin=

Good Luck!
Let me know what way you decide to go with this.

BobB · Post by **BobB** » Thu Nov 06, 2003 12:14 pm

This is freebie glass I'm working with. And am just throwing around some ideas and ways to use these pieces.

I'll post pics once I'm done. Thanks for the research on the hinges and weights you've done. Good stuff.

BobB