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Topic: Glass evenly heating

I have found that printing on glass seems to work very well as most of us may have found out. However, there is a problem with even heat transfer from the original aluminum platform to the glass. My build platform had a severe bend in it so there was a lot of air between the glass and the aluminum. In order to get this fixed all I did was run some oil on the aluminum before putting the glass on. It works very well, the glass is now evenly heated . Make sure to catch any spillover when you put too much oil on, just to prevent a mess.

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Re: Glass evenly heating

Good idea, I wonder if thermal paste as used for CPU heatsinks might not be a better idea.

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Re: Glass evenly heating

Gomisan wrote:

Good idea, I wonder if thermal paste as used for CPU heatsinks might not be a better idea.

Thermal paste is good, but be aware it's carcinogenic and you really don't want to be wiping your hands with it daily (accidentally as you switch the glass plate on and off, if you do that frequently as I do.)

Mineral oil, though less conductive than thermal paste, is much more conductive than air, totally safe (laxative if ingested, tho), and doesn't spoil (not that thermal paste does.)

4 (edited by Gomisan 2013-09-26 00:08:57)

Re: Glass evenly heating

http://lmgtfy.com/?q=is+thermal+paste+carcinogenic#

Before making claims that something is a carcinogen, you really should at least take the time to verify such a claim.

It 'may' be that some pastes have contained known carcinogens, but as with anything you use you should be able to get an MSDS and use it appropriately.

AFAIK, most thermal pastes these days use silver and silicon. Possibly older Beryllium based substances were toxic to a degree, but I don't think they use it anymore.

So really, don't believe every tale someone tells on the internet.


(I'd be more worried about the fumes from printing and acetone we all use!)

5 (edited by Tomek 2013-09-27 01:06:58)

Re: Glass evenly heating

Gomisan wrote:

http://lmgtfy.com/?q=is+thermal+paste+carcinogenic#

Before making claims that something is a carcinogen, you really should at least take the time to verify such a claim.

It 'may' be that some pastes have contained known carcinogens, but as with anything you use you should be able to get an MSDS and use it appropriately.

AFAIK, most thermal pastes these days use silver and silicon. Possibly older Beryllium based substances were toxic to a degree, but I don't think they use it anymore.

So really, don't believe every tale someone tells on the internet.


(I'd be more worried about the fumes from printing and acetone we all use!)

Hi Gomisan,

I'm not just intentionally willy-nilly repeating things from the internet - I'm basing this off of the words I was told at a past summer-job while I was a solder&assembly minion. I should have gone off with a disclaimer that the higher quality pastes- any that you buy off shelf- are likely to be more friendly, but that I would suspect the cheap as dirt paste you can buy off DX and similar mainland based sellers is more likely to be toxic if the toxic preparation is cheaper. And I suppose I am interchanging carcinogenic and toxic which are not the same thing, but hey, I'm just trying to get a mild point across and wasn't intending to go for the "everything will kill you" line. Instead, I mean that if you're going to interact frequently with the paste, as I would, because I have magnet mounted glass plate that I switch out frequently, then you might want to be aware if the paste is carcinogenic or not or that it has a chance of being the kind that is. 

I can see how you're irritated but give me a break, when we store things in our mind as fact we don't always double check that fact. I appreciate you calling me out this time so I know better in the future.

And, even if paste is bad, if you're not interacting with it frequently then I would not worry so much. But I started off printing thinking "of the fumes and acetone won't kill me" but it's been a year and so I've recently worked hard to reduce my exposure because it's clearly not one-off exposure.

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Re: Glass evenly heating

All good mate, I just get annoyed sometimes at things that get repeated without thought. Like MSG causing 'chinese restaurant syndrome'.. which it's doesn't  smile

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Re: Glass evenly heating

Acetone is a metabolic by-product.  Your body makes it by burning sugar (if you are a diabetic, you make even more of it).  The EPA does not consider it a toxic substance.  It can irritate your skin, so don't bath in it.

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Re: Glass evenly heating

Tomek wrote:

Thermal paste is good, but be aware it's carcinogenic and you really don't want to be wiping your hands with it daily (accidentally as you switch the glass plate on and off, if you do that frequently as I do.)

Whenever I use thermal grease, I clean-up all excess by wiping, then disposing the contaminated towels.

+1 on using the correct MSDS. The big problem for the thermal grease I use is eye irritation, so I clean up everything, then wash my hands after usage to remain safe.

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Re: Glass evenly heating

Has anyone tried one of those grey heat-conductive silicone pad things? Looks like a couple of dollars on the net. Might give a bit more squish if it's badly warped?

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Re: Glass evenly heating

I've head reports of this working, but it is a case of taking Everything apart to adjust the bed.

the way I've done it is...

use thick glass, I've got a 5mm thick slab of tempered glass (the stuff that's usually used for making windows on woodburning stoves so that you can see the flame.

I've drilled holes through the glass (using the aluminium bed as a template.

I've stuck (with kapton) a long and snaking length of nichrome wire under the bed keeping the same resistance as the stock resistor...

my bed is as easy to adjust as the stock product, heating sees completely even over the bed. -I guess the only thing that I actually miss compared to most bed conversions is the ability to take the glass off, but then I also miss out on crashing the head into bulldog clips and miss out on the glass ever shifting...

it's not an easy conversion, (but it is pretty cool to be able to see straight through the build area.)

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Re: Glass evenly heating

Tomek wrote:
Gomisan wrote:

http://lmgtfy.com/?q=is+thermal+paste+carcinogenic#

Before making claims that something is a carcinogen, you really should at least take the time to verify such a claim.

It 'may' be that some pastes have contained known carcinogens, but as with anything you use you should be able to get an MSDS and use it appropriately.

AFAIK, most thermal pastes these days use silver and silicon. Possibly older Beryllium based substances were toxic to a degree, but I don't think they use it anymore.

So really, don't believe every tale someone tells on the internet.


(I'd be more worried about the fumes from printing and acetone we all use!)

Hi Gomisan,

I'm not just intentionally willy-nilly repeating things from the internet - I'm basing this off of the words I was told at a past summer-job while I was a solder&assembly minion. I should have gone off with a disclaimer that the higher quality pastes- any that you buy off shelf- are likely to be more friendly, but that I would suspect the cheap as dirt paste you can buy off DX and similar mainland based sellers is more likely to be toxic if the toxic preparation is cheaper. And I suppose I am interchanging carcinogenic and toxic which are not the same thing, but hey, I'm just trying to get a mild point across and wasn't intending to go for the "everything will kill you" line. Instead, I mean that if you're going to interact frequently with the paste, as I would, because I have magnet mounted glass plate that I switch out frequently, then you might want to be aware if the paste is carcinogenic or not or that it has a chance of being the kind that is. 

I can see how you're irritated but give me a break, when we store things in our mind as fact we don't always double check that fact. I appreciate you calling me out this time so I know better in the future.

And, even if paste is bad, if you're not interacting with it frequently then I would not worry so much. But I started off printing thinking "of the fumes and acetone won't kill me" but it's been a year and so I've recently worked hard to reduce my exposure because it's clearly not one-off exposure.

I too work in the computer industry and I've been in contact with Thermal grease/paste for years, and I still have all my hair (although I can't make the same claim about my brain cells).

Anyway, this entire "thermal paste is carcinogenic" stuff has been passed around for years and to this day no one has yet to prove long term ill effects of being in contact with thermal compounds.  So most of us in the business refer to this as an "urban myth".

Most of this got started when someone found out that in some extremely specialized application, thermal paste containing Beryllium Oxide was used.  Beryllium oxide can cause beryllium disease (a form of lung cancer) if inhaled as a powder/dust, so in some cases where BeO exists in powder form, or ceramics or solid BeO is likely to be sanded caution should be taken to prevent inhalation.

However in the average application (or the average use of thermal paste compounds), this is not an issue since the BeO would not be present in a powder form.  Additionally, BeO is very expensive, so it's not commonly used in consumer grade thermal paste, rather it's used in chip manufacturing.

Does this mean I would spread this stuff on 64 square inches with my bare fingers, probably not, but not because I'd be afraid, but because it would be really messy.

To print or, 3D print, that is the question...
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...and too much time on my hands.

12 (edited by adrian 2014-03-17 07:14:18)

Re: Glass evenly heating

Yes.. misunderstandings, or worse, misrepresentations of things can cause a lot of undue anxiety... - Just like peoples worries  and constant 'warnings' to others about acetone and constantly put forward as 'dangerous' - its a naturally occurring substance that is produced and disposed of in the human body as a standard metabolic process... be wary the pregnant diabetic if acetone scares you! smile

Anyway - as already stated - Always read the MSDS yourself, and when in doubt seek advice from professionals outside of the Internet - Misinformation can be dangerous... to society or your health smile

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Re: Glass evenly heating

adrian wrote:

Yes.. misunderstandings, or worse, misrepresentations of things can cause a lot of undue anxiety... - Just like peoples worries  and constant 'warnings' to others about acetone and constantly put forward as 'dangerous' - its a naturally occurring substance that is produced and disposed of in the human body as a standard metabolic process... be wary the pregnant diabetic if acetone scares you! smile

Anyway - as already stated - Always read the MSDS yourself, and when in doubt seek advice from professionals outside of the Internet - Misinformation can be dangerous... to society or your health smile

I bet you wish you had a dollar for every time you have posted a response to this issue big_smile

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