1 Topic by Staffordknot

  • Staffordknot
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Topic: Slow cool down of bed

I'd like to see a slow cool down feature for the bed... After my latest glass shattering it struck me a cool down cycle for he bed would be handy as I believe its contraction after cooling that causes glass to shatter not expansion on heat (usually)

2 Reply by Tomek

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Re: Slow cool down of bed

Change your end Code to something like 60 Celsius instead of "off."   I'm surprised, I rapid cycled  cheap 2mm glass plenty of times without a problem. it's slow to cool down because of thermal mass and the printer chamber being surrounded by walls. Never blew cold fans on it or anything.

3 Reply by nlancaster

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Re: Slow cool down of bed

I had a piece of glass break when i printed a part that was about 7x7 inches on my SD3.  While cooling "BANG!!!"  the glass broke.

4 Reply by adrian (edited by adrian 2013-06-20 04:23:06)

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Re: Slow cool down of bed

Borosillicate Glass (aka Pyrex) for the win.

Its designed for heating and cooling.

Standard glass is not.

Pick some up from one of many reprap ebay retailers .. I paid $15 a 200x214mm square shipped.... and it wont ever shatter except through physical mis-treatment

But standard glass is not annealed, and yes, will eventually develop fractures to the surface and fail spontaneously...
So use the pyrex - heat cycles is what its made for smile No need for fancy cool down etc smile

Heres a link I've even UK-asised for you smile Only 13 quid! (I actually got 200x214 from somewhere, as I wanted some spare room for clipping it down...) smile
http://www.ebay.co.uk/itm/Borosilicate- … 3383057aab

5 Reply by Staffordknot

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Re: Slow cool down of bed

I think my problem is i went above 110c, i'm not sure exactly what temp but it was scolding. I'm not sure why but i remember from somewhere that normal glass doesnt like going over this temp.