What glue/adhesive use for Sendust/Kool Mu E core assembly ?

[Miyuki]

Hi folks,

do you have any recommended glue for bonding E cores made from Sendust together and also for mounting core to PCB ?

[coppercone2]

thin superglue or manufacturers recommendation

[Miyuki]

So I have reply from manufacturer, if you need to glue this type of material:

This powder type material cannot be glued by thin superglue, but can be used thick rubber filled superglue like Loctite 410, Cyberbond 2241
Or use two component epoxy

[jbb]

I suggest you check the temperature rating on the glues too - superglue may come unstuck...

[gka_0509]

"Resinlab EP950G is a one part epoxy adhesive that is recommended for use on Powder Core materials. This adhesive has good strength at room temperature and retains strength at high temperature."
https://www.mag-inc.com/Products/Powder-Cores/Learn-More-about-Powder-Cores

[coppercone2]

why wont thin superglue work? I thought it would give better thermal contact

[schmitt trigger]

I remember asking that same question many years ago.
If my memory serves me well, dust cores are porous, and superglue does not properly fill all the voids.

[Bud]

I have not seen anything that could not be fixed with a 2-component epoxy tube out of a dollar store.

[coppercone2]

I remember asking that same question many years ago.
If my memory serves me well, dust cores are porous, and superglue does not properly fill all the voids.

Does it like keep wicking into the core? Maybe it penetrates and the thermal cycling stressed it because of dissimilar tempco of the two materials. Might make signal applications suffer?

[T3sl4co1l]

Superglue may be too brittle or sensitive to temperature.

Transformer varnish is also an option, which helps with the windings as well (preferably vacuum impregnated).

Tim