Clear cast 1-I was recently advised not to pour on or in glass ?? I have been, and now concerned if they will explode with temp changes?? I did have one crack in a freezing car over night , but that I understand - I have sent several coasters to Florida and not sure if I should continue embedding items glass coasters? 2-I was warned about cleaning my accidental exposure with alcohol? I have been doing this and told that breaks up the chemicals and easily able to enter into your bloodstream and cause dangerous exposure ? 3-I just run a fan Blowing towards the bathroom and keep the bathroom fan on that is directly off the basement I pour in ?
Let me copy what I said on the other thread for #1**
Once the resin is poured and has fully cured, it's considered "stable" and should not break. I keep my castings and mold boxes in a room that is fairly un-insulated and have not had a problem when the room reached below freezing several times - the clear has never even cracked from that. The glass probably broke due to a quick change in temperature which is what glass will normally do especially if it's thin or it's not "tempered" glass like a window pane.
If they are coasters, I'm assuming they'll be used inside so you should have no worries about them exploding due to a temperature change. Other than that, I am 99.9% sure you are safe in pouring resin onto and over glass and don't need to worry about it exploding.
If anything breaks, I'm fairly sure it would be the glass and not the resin - I've used the Clear on some of my mold box bottoms to level out the bottom or fill in any cracks under the castings and on one of my most bought molds it is just now starting to have problems due to my rough handling (I'm very rough on it too) and to understand how long it lasted you have to know that I've made this mold design over 10 times. This is a thin layer and the Clear can really handle not only the temperature extremes but all the prying and flexing I do to it so a little thing of shipping them and regular use should not make them explode or break unless the glass itself is what breaks.
Now I would not be dropping them from like 3 stories high just to test that out or baking them in the oven then pulling them right from the hot oven to a 70 degree room. That's stuff that would cause the glass itself to break and it wouldn't be the resin's fault. I hope this helps you.
#2 Yes alcohol is what is normally used to clean up and it does break down the chemicals but normally you wear gloves when handling alcohol so your exposure level is very, very low and if you wash your hands after clean up and removing the gloves you should be fine. I use Disinfecting Wipes myself and half the time I am using them barehanded and I have had no problems. And I'm one of those people who it would show up immediately on if there was any problems.
#3 If you have a fan blowing then you've got ventilation and having the bathroom fan on is a good extra precaution so you're doing it right. Again, I'm one who would know immediately if there is a problem - I once caught some kind of gas leak seconds after it started in a grocery store I was working in and it was just a tiny leak (it was a small leak above the register through the vent but we evacuated the customers just in case) but I caught it before anyone else and caught it right away. If you can smell the fumes and you're still worried, you could also get a air purifier for the room. If there are no windows there (you mentioned a basement), I'd get one just in case. And keep your fan on high for at least an hour after you finish working just to be sure the fumes don't even get a chance to think about settling on anything and go right out the bathroom fan's exhaust.
Ok thanks for the info ! My concern is the glass breaking not the resin- I plan to pour over a glass table with black resin but the four season room dies get pretty cool and pretty warm I don’t want the glass to crack ?!
......If anything the resin will act as an insulator between the elements and the glass. Something to think about....the windows in my garage are exposed to triple digit temps for hours at a time in the Summer and zub zero temps in the Winter with no issues. Now if I where to throw ice water at a window when its 100 degrees + I really doubt that it would crack, break or shatter..... same could be said for throwing hot water on a cold window in sub zero weather. The only way that expansion or contraction of glass would be enough to damage the glass would be if it where exposed to excessive heat over a duration of time such as a structure fire as a example.
I forgot about the insulation benefit but the table would have to be completely enclosed for it to work like the tempered glass of a window as tempered glass is exposed to extremes to make it tempered. If it's going to be in an actual room, you still should be okay as the air in the room will act to keep the whole room fairly level in temperature as the whole room will need to warm up/cool down to get to the extremes that will cause glass to break. And a good size room should be harder to go to extremes quickly enough to break glass. The resin might actually keep the glass together to a point if the glass just cracks - it's something to think about.