Alumina oxide powder proportion

[Ledean]

I have some alumina oxide powder from the sandwich shoppe.
I am looking for a cheaper alternative than AA.
What epoxy do you use to make a thermal blog, and what are the proportions used to mix with the epoxy with alumina oxide.
I do not want to put too much epoxy and loose out on the thermal transfer.

Can JB weld be called an epoxy?
Thanks
Ledean

 

[rdshores]

Check out this link: MAKE YOUR OWN THERMAL EPOXY
It's not exactly what you aaked for, but it may help.

 

[dat2zip]

The critical thing to do is to ensure you do not trap air bubbles in the ALumina Oxide Powder. I've found that starting with thicker epoxy will form little clusters or balls of powder that are not fully dissolved and thus have trapped air.

You might need to vacuum pump out the air, stir in the powder slowely or some other method. Starting with thinner epoxy will make it easier and less forgiving of creating trapped lumps.

The more you can blend in the epoxy the better the thermal efficiency will be.

Wayne

 

[NewBie]

Blend into one half first, work the bubbles all out with vacuum or centrifuge (may need stirred again).

Then mix the two expoy halves.

 

[IsaacHayes]

Yup. Jar just said what I was typing the quick reply.

Is there any epoxies that tend to be thinner and not get trapped air bubbles? I'd like to find some for glowpowder mixing and would like to avoid the air bubles too.

Any brands that have good results?

 

[Ledean]

Thanks for all the replies.
Yea is there any particular brand of a good epoxy ?.
Ledean.

 

[NewBie]

Epo-Tek makes a number of them, and low cost, and can buy in bulk if need too.