Glass for wood stove door?

G'day Jim, From my time in retail glass, I found the type of glass found in slow combustion stoves is normally :

1/ Pyro Ceramic or 2/ Toughened Pyro C. is definitely better for the purpose, though frightfully expensive. Some stoves have PC fitted in vertical strips, very often in curved doors to get round the bend without the expense of a curved piece, and other times in flat situations (obviously using the offcuts to reduce wastage). They are just dry butted together with no major loss of heat. PC is usually 5mm thickness, though sources outside Australia may have other thicknesses available. Toughened was usually from 4mm to 6mm thicknesses. Both are prone to thermal shock, such as working temp glass being splashed with liquid etc. Also burning logs falling / leaning against the glass can break them. Pyro ceramic will crack, stay in place, and still be functional. Toughened will shatter into a spiderweb of pieces, possibly explode outwards, or (if it doesn't blow out straight away) eventually fall in or out. Older heater had an asbestos type gasket, but some where puttied in with a high temp (black coloured) putty like material. Other modern slow combustion stoves have a different asbestos-like material, that is apparently not harmful like asbestos is well know to be. Not sure what this new gasket material or the putty is actually named, but try your local combustion heater supplier. Pyro C. can be cut to size, toughened can be cut to size and then 'toughened'. Hope this helps.

I have a piece in mine that has been abused for 20 years. I believe it's quartz glass. Go to the fireplace shop and ask about the glass with an acetylene torch on one side and a stream of water on the other.

Hi Jim,

I agree with Jack. I would recommend quartz glass. I will commonly demonstrate the difference between Pyrex and Quartz by hitting the Quartz with a blue point oxy/fuel gas flame until white hot, and then douse it in water. Pyrex will normally crack, Quartz will not crack. It is the same type of glass used in the windows of the space shuttle. It has a high melting point.(above 2000 F) It can also take the thermal shock.,

It is readily available on the shelf from 1"x 1" to 6" by 6" squares or round disks from many glass vendors. You can get it in different thicknesses, 1/8", 3/16", 1/4". It increases in price dramatically the thicker you go.

I'm not sure, but I think what Les is referring to is Pyrex (Borosilicate glass) It can take a lot of heat, but not the sever thermal shock that quartz can withstand. The only reason you would want to temper it would be to satisfy some idiot authored government code. Tempering will not work on Quartz.

There are a lot of non asbestos, high temperature tapes, putties, and adhesives available that we use in scientific glass blowing. here are some links to one of the vendors I use. I'm not sure if the first one will work. the second is their home page. You should be able to find what you need from refractory suppliers, or kiln builders as well.

Hansen SC Glass Tech Scam Diego, Comi-fornia

Many refrigerators also use quartz glass tubes in the defrost units. They contain a heating coil inside that gets red hot during defrost. Water often drips on the tube with no problem. One of those things you have to see to believe.

That sounds like the best product for sure Randy. The demo Jack describes sounds almost unbelievable, they actually use that as a demonstration ? Possibly so from your reply Randy. Pyro Ceramic in recent years appeared pink ish in colour (in the 5mm ish thickness), while I recall earlier on in my time in retail flat glass it could have had a brown / yellow ish tinge in possibly 4mm thickness. It was then approx retail $800AUD a square metre, (12" x 10" piece would have been about $48.00AUD), which was very high even when compared to other specialty flat glass types. I'll try to get some info on quartz glass to satisfy my curiosity, thanks.