Might be one for TNP as he knows about epoxy (hi waves)


Best glue for shiny neodymium magnet disc (5p sized) to plain ali?

Epoxy or hotglue. Or something else?


I'm aware ali can be awkward due to oxide coating. And there will be
heavy thermal cycling, which killed the foam tape on some trunking - had
to screw that in the end.


Just wondered if anyone had experience?


Cheers - Tim



Why?

Have one of a series of mini projects is to put some led tape around the
conservatory using ali extrusion to make it nice:

https://www.marcled.com/p3-led-profi...-diffuser-opal


Going to be sticking on the removable uPVC strip that runs around at the
top of the windows.

Don't want to drill it (so it cabn be restored later if lights become
defunct).


So I'm going to hotglue chunky steel washes to the back of it and
replace, then glue neodymium disc magets about the side of a 5p coin to
the back of the ali extrusion.

No doubt that it will hold well.

On 06/02/2020 19:45, Tim Watts wrote:
Might be one for TNP as he knows about epoxy (hi waves)


Best glue for shiny neodymium magnet disc (5p sized) to plain ali?

Epoxy or hotglue. Or something else?



Ive generally found that car body filler is better than epoxy for most
hack jobs, but its a pain to buy a huge tin if you dont have any.

hot gl;ue willwork biut its noyt that strong.

On balance degrese and use epoxy and warm it a bit before use



I'm aware ali can be awkward due to oxide coating. And there will be
heavy thermal cycling, which killed the foam tape on some trunking - had
to screw that in the end.

neodymium magnets lose their mojo at between 50C and 100C depending on
exact chemistry.

I'd say that means epoxy then. Or car body filler.



Just wondered if anyone had experience?


Cheers -Â* Tim



Why?

Have one of a series of mini projects is to put some led tape around the
conservatory using ali extrusion to make it nice:

https://www.marcled.com/p3-led-profi...-diffuser-opal



Going to be sticking on the removable uPVC strip that runs around at the
top of the windows.

Don't want to drill it (so it cabn be restored later if lights become
defunct).


So I'm going to hotglue chunky steel washes to the back of it and
replace, then glue neodymium disc magets about the side of a 5p coin to
the back of the ali extrusion.

No doubt that it will hold well.



--
Climate Change: Socialism wearing a lab coat.

On 06/02/2020 19:45, Tim Watts wrote:
Might be one for TNP as he knows about epoxy (hi waves)


Best glue for shiny neodymium magnet disc (5p sized) to plain ali?

Epoxy or hotglue. Or something else?


I'm aware ali can be awkward due to oxide coating. And there will be
heavy thermal cycling, which killed the foam tape on some trunking - had
to screw that in the end.


Just wondered if anyone had experience?



I've found the the shiny silver coating on the magnet is the weakest
bond (to the rest of the magnet) and just relying on sticking to that
will result in it soon failing.

As you indicate, I've used a magnet with a hole that can take a screw.

Alternatively use epoxy to encapsulate the whole magnet as well as
sticking it down. Perhaps drill a small hole in the ali so that the
epoxy also flows through it forming a glue bridge front to back (easier
if gluing to a horizontal surface).

Sandwich the magnet between in between two pieces of material that are
physically joined so the magnet cannot move.


--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 07/02/2020 02:19, The Natural Philosopher wrote:
On 06/02/2020 19:45, Tim Watts wrote:
Might be one for TNP as he knows about epoxy (hi waves)


Best glue for shiny neodymium magnet disc (5p sized) to plain ali?

Epoxy or hotglue. Or something else?



Ive generally found that car body filler is better than epoxy for most
hack jobs, but its a pain to buy a huge tin if you dont have any.

hot gl;ue willwork biut its noyt that strong.

On balance degrese and use epoxy and warm it a bit before use



I'm aware ali can be awkward due to oxide coating. And there will be
heavy thermal cycling, which killed the foam tape on some trunking -
had to screw that in the end.

neodymium magnets lose their mojo at between 50C and 100C depending on
exact chemistry.

We're probably talking 30, 40C extreme peak in summer on a bad day. 5C
in winter.


I'd say that means epoxy then. Or car body filler.


Cheers for that

On 07/02/2020 09:38, alan_m wrote:
On 06/02/2020 19:45, Tim Watts wrote:


I've found the the shiny silver coating on the magnet is the weakest
bond (to the rest of the magnet) and just relying on sticking to that
will result in it soon failing.

As you indicate, I've used a magnet with a hole that can take a screw.
I also considered that, but there's not much to lose a thread into on
the ali. They come with little spring clips that are also designed to
take a countersunk screw like the magnets. Unless I screw from both
directions into a pad of some sort... Maybe a little block of nylon or
something that can easily take a thread.


Alternatively use epoxy to encapsulate the whole magnet as well as
sticking it down. Perhaps drill a small hole in the ali so that the
epoxy also flows through it forming a glue bridge front to back (easier
if gluing to a horizontal surface).

Sandwich the magnet between in between two pieces of material that are
physically joined so the magnet cannot move.
Some ideas that - thanks for suggesting them

On Thursday, 6 February 2020 19:45:47 UTC, Tim Watts wrote:
Might be one for TNP as he knows about epoxy (hi waves)


Best glue for shiny neodymium magnet disc (5p sized) to plain ali?

Epoxy or hotglue. Or something else?


I'm aware ali can be awkward due to oxide coating. And there will be
heavy thermal cycling, which killed the foam tape on some trunking - had
to screw that in the end.


Just wondered if anyone had experience?


Cheers - Tim



Why?

Have one of a series of mini projects is to put some led tape around the
conservatory using ali extrusion to make it nice:

https://www.marcled.com/p3-led-profi...-diffuser-opal


Going to be sticking on the removable uPVC strip that runs around at the
top of the windows.

Don't want to drill it (so it cabn be restored later if lights become
defunct).


So I'm going to hotglue chunky steel washes to the back of it and
replace, then glue neodymium disc magets about the side of a 5p coin to
the back of the ali extrusion.

No doubt that it will hold well.

Drill some holes in the aluminium to help the glue stick to it.