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Please Help. I am making a grandfather clock type Display Case with glass sides (set in wood frames), and a glass door (also set in a wood frame).

Do you think I should use Quarter-inch thick glass or Eighth-inch thick glass????

Tempered glass or not tempered???

Thanks for any advice you can give me.
 

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I'd think common window glass would be fine, which is about 1/8" thick. 1/4" thick glass will be pretty heavy. It's not going to be under any stress, so I don't think it would have to be very strong.

You'll also want to consider how it will be cut. You can cut 1/8" thick regular glass yourself fairly easily. I don't know how tempered glass is cut - i.e. I don't know if a simple scoring glass cutter works on tempered glass because of its structure.

You could also just go look at some commercially-made clocks and see what they use. Of course, if they're using beveled glass, that would have to be thicker just to accommodate the bevel.
 

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You can't cut tempered glass. You order it in the final size. It's not too pricey but a bit tricky to work with. I was carrying a large piece and the stress from me holding it caused it to fracture.

Your clock probably won't be in a high traffic area so 1/8" regular glass will be fine.
 

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You can't cut tempered glass. You order it in the final size. It's not too pricey but a bit tricky to work with.
+1.:yes: For DIY, do not attempt to cut it.

For the most part ⅛" double strength`glass would be fine. For beveled glass up to 1" bevel,3/16" glass works out well. You can cut glass fairly easy up to ¼" thick with an oiled carbide wheeled cutter.






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You didn't say anything about the size of the glass or how it will be installed. If you plan on using a keeper molding you have to account for that, the glass and any bead left on the frame. In most cases, 1/8" ordinary window glass is fine. Large sizes or the possibility of the glass being struck, kids playing, museum case, etc. may require thicker or shatter proof glass.

An option you might consider is using art glass, the types they use for stained glass windows. There are many different choices, clears, colors, textures, wavy antique looking. I think there are two projects in my pictures that used this type of glass. The console cabinet is clear but a little wavy, the jewelry cabinet has colored, textured glass. This glass is usually a bit thicker, 3/16" and fairly tough.
 

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The real question is how low is the glass to the floor and if you have young children in the house. Tempered glass is harder to break and when it does it would shatter into pieces rather than large pieces that could come out and cut. I do think 1/4" glass is overkill. It just adds unnecessary weight to the clock. The clock I made in high school I used single strength glass in the doors and it still has the original glass in it.
 

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You'll also want to consider how it will be cut. You can cut 1/8" thick regular glass yourself fairly easily. I don't know how tempered glass is cut - i.e. I don't know if a simple scoring glass cutter works on tempered glass because of its structure.
Tempered glass has to be scored both side, snapped and the have a blade run down the crack to sever the plastic laminate. Lots of very precise work, id avoid it.

Personally, id go with 1/8 thick. Its not load bearing nor under extreme stress, so the double thickness would probably be wasted
 

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Tempered glass has to be scored both side, snapped and the have a blade run down the crack to sever the plastic laminate. Lots of very precise work, id avoid it.
Where did you get this bit of erroneous wisdom? You can't cut tempered glass.

Personally, id go with 1/8 thick. Its not load bearing nor under extreme stress, so the double thickness would probably be wasted
Where did you get this bit of erroneous wisdom? Double strength is not double thickness...just double strength.







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The thickness of single strength glass is 2.5mm and the thickness of double strength glass is 3.2mm. I think double strength glass for the clock would work fine. I don't think it's worth it to go with tempered glass. It would be safer. You don't really cut tempered glass. You order it to the size you need and the glass company cuts it and then tempers it. In order to cut tempered glass it must be heated to remove the temper, then cut it and then re-tempered. Still this process isn't for the do it yourselfer and has a high failure rate and generally not worth the trouble.
 

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Tempered glass has to be scored both side, snapped and the have a blade run down the crack to sever the plastic laminate. Lots of very precise work, id avoid it.

Personally, id go with 1/8 thick. Its not load bearing nor under extreme stress, so the double thickness would probably be wasted
It's easy to confuse them. There is safety glass which is tempered and some that is laminated. The glass that is laminated and not tempered can be cut but tempered glass will shatter in a million pieces if you try to cut it. For this clock the laminated glass might be a cheaper alternative to safety glass.
 

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Seriously: glass cutting is a very specialized task. I'd go to a glass shop and explain what you are trying to do. Try to speak to one of the craftsmen, if possible. If there is any chance of it being run into by small kids... I'd go with safety glass. That stuff is expensive and difficult to work with, or so I am told.

Remember: you are going to make it once, and pay for it once. You don't want to have to live with yourself if some kid gets cut up because you wanted to save on the cost of the glass.
 

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Tempered glass has to be scored both side, snapped and the have a blade run down the crack to sever the plastic laminate. Lots of very precise work, id avoid it.

Personally, id go with 1/8 thick. Its not load bearing nor under extreme stress, so the double thickness would probably be wasted
To correct myself, I said tempered but was thinking safety glass. Also, I realize that strength to thickness isn't a perfectly linear relationship, but at the same time, who cares, it's close enough.
 

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Where did you get this bit of erroneous wisdom? You can't cut tempered glass.



Where did you get this bit of erroneous wisdom? Double strength is not double thickness...just double strength.







.
i did google search and found lot's of information on cutting tempered glass ?? i don't belive i would go thro with this , just what i found How to Cut Tempered Glass

There is a special process that you must follow when cutting tempered glass, otherwise it will shatter and no longer be usable. It is important to use extreme caution as you go through the process so that you do not get injured.

Step 1: Clean the Tempered Glass Thoroughly

Make sure there is no dust or dirt particles that could get in the way of a clean cut. Clean it thoroughly with window washing solution and allow it to dry completely.

Step 2: Anneal the Glass

Heat the glass in a craft oven until it reaches 900 degrees Fahrenheit, then turn off the oven and allow the glass and oven to cool for 8 hours. This will make the glass so that it is no longer tempered and will not shatter when cut.

Step 3: Prepare the Glass for Cutting

After the glass has been annealed, place it on a flat surface and place a t-square over the place you wish to cut it. The dip your glass cutter into kerosene. This will allow for a cleaner cut.

Step 4: Cut the Glass

Pressing down with moderate pressure, run the cutter along the straight edge in one smooth motion to make a thin line across the top of the glass. Do not run the cutter over the glass again. Place the dowel under the line and press downward on both sides of the dowel, making sure to wear protective clothing. This should snap the glass evenly down the line.

Step 5: Smooth the Edges

Smooth the edges by running them against a whetstone. Not only will this make the glass smoother and less dangerous to carry, it will also strengthen the glass.
 

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Step 2: Anneal the Glass

Heat the glass in a craft oven until it reaches 900 degrees Fahrenheit, then turn off the oven and allow the glass and oven to cool for 8 hours. This will make the glass so that it is no longer tempered and will not shatter when cut.
So, the process for cutting tempered glass involves making it not tempered anymore. Hmmm, ya learn something new every day!
 
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