Making Breakable Glass

[Valiss]

Our guild is a tavern, and as such, we can occasionally put on a "bar fight" for the paytrons.  It's a fun, scripted show.  What I would like to incorporate is the classic "breaking a bottle over the head" scene that occurs in every bar fight.  Now I have read that you can make breakable "glass" from sugar, but I have yet to try it.  There are a ton of recipes on the internet for this, so I wonder: have any of you made this?  How did it work for you?  Do you have a recommended recipe?

Thanks!

[Sitara]

I've never tried to make a bottle but have made panes of "glass".  Be careful, as if you make it too thick, it can still hurt.  As far as bottles, I have bought that type at costume and magic stores.

[Valiss]

How did you make the glass panes? 

It never occured to me that you can purchase these items.  Perhaps I'll have to call some local shops to see if they carry this kind of thing.

[Magister]

Valiss:

  This is sort of like asking how to make a Corvette out of common household materials.

  The person above who said, "you can buy them from magic stores" is correct - and if you have the money to spend I would HIGHLY recommend you go that route.  Expect to pay around $100.00 for 6 bottles.  Somewhere around $15 - $20 bucks each.

  Several options from theatre prop companies are:

http://www.theatrefx.com/store/commerce.cgi?product=breakaway_glass

http://www.alfonsosbreakawayglass.com/

http://www.jmfx.net/breakaway_glass.html

http://www.10outof10.co.uk/acatalog/Breakable_Glassware__props_.html

http://www.backlotprops.com/index.php?main_page=index&cPath=322_272&zenid=00cfa75ff6500e99c022303f77f821bf

  Ok.. now on to the - if you're nuts like some of us and just have to try it yourself.

This is where things complicated.  You have several choices of how to go about it.

First, sugar glass, or "breakaway" plastic.  Both have their benefits, and weaknesses.  Almost everything you will find above is the plastic.  It's easier for commercial companies to deal with, and doesn't melt at room temperature like sugar glass (makes storage, shipping, and handling easier).

For the home hobbyist though, it's more expensive, can require expensive equipment, and you may have to learn how to blow glass just to boot.  But.. for that headache if you do it right, you get a good end product with all the benefits of above.  Make them, and store them.

Then there is sugar glass.  Can be made on your stove.  Ingredients are cheap.  Doesn't "require" (notice the quotes), special equipment, and the biggest risk you have is severe sugar burns - don't underestimate the pain this can cause.  It's like napalm.. sticky, and oh boy does it burn.

Drawbacks - must be kept refrigerated until used.  Doesn't last long at room temperature - will start to "melt" and get sticky (it is sugar afterall), and may just "bend" over the actors head and not shatter.  Glass usually looks a little "cloudy" - getting a perfectly clear one is very difficult.  Adding food coloring / dye can help cover this up.

Ok.. once you've chosen your medium, you need to see if it requires, "blowing" (the plastic is heated in a crucible, and "blown" just like you would blow regular glass), or can be made with a mould (most use moulds now).  Sugar glass will always use a mould.

If you use a mould, you need to either buy one made for the bottle you want, or make one.  Explaining how to make a bottle mould would be a book in itself.  So.. if you want a good book on making props and moulds that includes information on this such topic look for, "The Prop Builders Molding & Casting Handbook" by Thurston James.  Check your local interlibrary loan.

Silicone moulds work the best.  Make sure you use a "release" agent on the mould.  Bottle moulds are usually tricky at best, infuriating most of the time.  Make sure the medium is well and evenly heated, and you get a good pour.  Especially with sugar glass.

As for sugar glass recipes - you are right the 'net it full of them.  Try a few until you find one you like. 

As for the plastic (urethane / rubberized).  A few suppliers are:

http://www.reynoldsam.com/index.php?cPath=5_1120_1164

http://www.eagerplastics.com/rubberglass.htm

  If you have any specific questions, or need help let me know... Good luck whichever way you decide to go.

     - Mag

[Valiss]

Thanks for all the great info.  I was hoping that this would be a fun, easy and cheap thing to do, but this is more work (and money) than I would put into it.  Thanks for all the info though.  I still may track down a seller and get a few just for fun.