Alex Coleman wrote:
On 01 Apr 2007, OG wrote:

"Derek Geldard" wrote in message
...
On Sun, 01 Apr 2007 18:35:22 +0100, Alex Coleman
wrote:

On my rather old tube of 'regular' Araldite it says it is ok for
metal.

It is OK for metal.

If this is so then why would I ever use one of those 2-part
adhesives sold specially for metal? I mean the sort of thing that
is usually coloured grey and can often be bought in car accessory
shops?
Sundry other reasons. If it's what I'm thinking about they contain
a lot of inert filler, it helps filling holes and gaps. The grey
colour is to convince the proles they can fix holes in grey metal
with it.

I need to glue an aluminium ring (about 1.5 inches diameter and
about 4mm thick) to a plastic base. There will be some light to
moderate stressing of this arrangement when it is in use.

I figured the Araldite was just fine for the plastic but what
about the metal?
It's fine on aluminium per-se.

Less so on plastic, and it depends which plastic.

Set araldite is brittle, if the whole assembly will deflect under
load the joint may break up.
I use a little less hardener if I think a bit of 'give' is needed.



Doesn't using less hardener with Araldite slow down the rate of
curing rather than give an incomplete (and therefore more flexible)
cure?

Actually it isn't hardener. Its two parts of the glue which have to be
mixed thoroughly and in equal proportions. All that less of one part
does is leave pockets of the other unset.