Aluminium
 

quite some years ago I used to by electronic magazines and some usefull
tips where given in them.
anyway one tip I remember which I want to do now but have forgotten the
process?
The process involved dipping aluminium panels in caustic soda for a few
minutes whereby it gave the surface/facia a very hard resiliant
surface,almost none scratchable.

Does anyone know the strenght of the formula and time to keep it in the
caustic soda?

Thanks
--
Sir Benjamin Middlethwaite

Aluminium
 

In article ,
The3rd Earl Of Derby wrote:
quite some years ago I used to by electronic magazines and some usefull
tips where given in them.
anyway one tip I remember which I want to do now but have forgotten the
process?
The process involved dipping aluminium panels in caustic soda for a few
minutes whereby it gave the surface/facia a very hard resiliant
surface,almost none scratchable.

Does anyone know the strenght of the formula and time to keep it in the
caustic soda?

These people do kits for all sorts of metal finishes. Their cat. gives
quite comprehensive details - but you'll have the to check the website
yourself to see if it does too as I'm off to watch TV.
http://www.frost.co.uk/

--
*Why is the word abbreviation so long? *

Dave Plowman London SW
To e-mail, change noise into sound.

Aluminium
 

The3rd Earl Of Derby wrote:

The process involved dipping aluminium panels in caustic soda for a few
minutes whereby it gave the surface/facia a very hard resiliant
surface,almost none scratchable.

I think caustic soda would just dissolve the aluminium.

It's not anodising, is it?

Anodising increases the thickness of the surface oxide layer, which is
absorbent and can be dyed to pretty colours. That's also why they can't
get all the paint off underground trains when they've been defaced by
morons with spray cans.

Idiots' anodising guide here;
http://www.creative-chemistry.org.uk.../anodising.pdf

Caustic soda is involved, but only for initial cleaning. The anodising
solution uses sulphuric acid.

If it's not anodising, then just ignore that.

Aluminium
 

Aidan wrote:
The3rd Earl Of Derby wrote:

The process involved dipping aluminium panels in caustic soda for a
few minutes whereby it gave the surface/facia a very hard resiliant
surface,almost none scratchable.

I think caustic soda would just dissolve the aluminium.

It's not anodising, is it?

Anodising increases the thickness of the surface oxide layer, which
is absorbent and can be dyed to pretty colours. That's also why they
can't get all the paint off underground trains when they've been
defaced by morons with spray cans.

Idiots' anodising guide here;
http://www.creative-chemistry.org.uk.../anodising.pdf

Caustic soda is involved, but only for initial cleaning. The anodising
solution uses sulphuric acid.

If it's not anodising, then just ignore that.

Thanks for that,but no it didn't disslove it as it was not in the caustic
solution long enough for this to happen bearing in mind also its strenght.

I have done this ,but as i said it was quite some years ago.

The process gave the aluminium surface an semi matt appearence something
like brushed aluminium.

--
Sir Benjamin Middlethwaite

Aluminium
 

Aidan wrote:

I think caustic soda would just dissolve the aluminium.

It's not anodising, is it?

Anodising increases the thickness of the surface oxide layer, which
is absorbent and can be dyed to pretty colours. That's also why they
can't get all the paint off underground trains when they've been
defaced by morons with spray cans.

Idiots' anodising guide here;
http://www.creative-chemistry.org.uk.../anodising.pdf

Caustic soda is involved, but only for initial cleaning. The anodising
solution uses sulphuric acid.

If it's not anodising, then just ignore that.

I was looking at this site,similiar to what you posted.
http://astro.neutral.org/anodise4.shtml


--
Sir Benjamin Middlethwaite

Aluminium
 

In message , The3rd
Earl Of Derby writes
quite some years ago I used to by electronic magazines and some usefull
tips where given in them.
anyway one tip I remember which I want to do now but have forgotten the
process?
The process involved dipping aluminium panels in caustic soda for a few
minutes whereby it gave the surface/facia a very hard resiliant
surface,almost none scratchable.

Does anyone know the strenght of the formula and time to keep it in the
caustic soda?

Not long - caustic soda will eat aluminium with vigour

--
geoff

Aluminium
 

The message . com
from "Aidan" contains these words:

I think caustic soda would just dissolve the aluminium.

It does if you leave it in too long, but I've done it - oddly, from a
suggestion in a very old electronics mag, and a pint of warm water with
a tablespoon full of caustic soda in it does produce a passable finish.

Anodising it is not - nor is it a patch on proper anodising, but it's OK
for some uses.

--
Skipweasel
Pay no attention to that man behind the curtain.

Aluminium
 

Hi there
FWIW I remember this too - as distinct from anodising, which I also
know and have a had a go at. I was a schoolkid when I tried - about all
I can remember is:

- it must have been pretty string as I'm fairly sure it was a
satisfyingly 'bubbly' mixture, and yes I do know to add soda to water
- I think I first prepared the Al by scrubbing it with steel wool. IIRC
this was part of the process; the action of the Caustic solution on the
'grain' of the metal created this way was part of the point.
- I think the panels went in for only a short time, say 30secs.

Sorry I can't dredge up more. Have you tried somewhere like the
repairfaq?

jon N

Aluminium
 

Guy King wrote:
The message . com
from "Aidan" contains these words:

I think caustic soda would just dissolve the aluminium.

It does if you leave it in too long, but I've done it - oddly, from a
suggestion in a very old electronics mag, and a pint of warm water
with a tablespoon full of caustic soda in it does produce a passable
finish.

Anodising it is not - nor is it a patch on proper anodising, but it's
OK for some uses.

John Haigh mode on
but where can I obtain Sulphuric Acid?

--
Sir Benjamin Middlethwaite

Aluminium
 

The message
from "The3rd Earl Of Derby" contains these words:

but where can I obtain Sulphuric Acid?

Old batteries.

--
Skipweasel
Pay no attention to that man behind the curtain.

Aluminium
 

In article ,
Owain wrote:
- but you'll have the to check the website
yourself to see if it does too as I'm off to watch TV.

I didn't think The Bill was on tonight :-)

Watch that rubbish? ;-)

Naw - it was Judge John Deed I wanted to see. ;-)

--
*Sticks and stones may break my bones but whips and chains excite me*

Dave Plowman London SW
To e-mail, change noise into sound.

Aluminium
 

In article ,
The3rd Earl Of Derby wrote:

The process involved dipping aluminium panels in caustic soda for
a few minutes whereby it gave the surface/facia a very hard
resiliant surface,almost none scratchable.

Caustic soda etches aluminium, removing the protective
oxide film. It has to be handled carefully in this state
because it stains so easily. However a thin oxide film
does grow back fairly quickly. Professional anodising
grows a thicker film by electrolysis.

Radiospares used to do an aluminium labelling system
(was it Copyphot?) where the final stage was to immerse
the label in a hot solution of some magic salts that
chemically grew the protective oxide film.

--
Tony Williams.

Aluminium
 

"Guy King" wrote in message
...
The message . com
from "Aidan" contains these words:

I think caustic soda would just dissolve the aluminium.

It does if you leave it in too long, but I've done it - oddly, from a
suggestion in a very old electronics mag, and a pint of warm water with
a tablespoon full of caustic soda in it does produce a passable finish.

Anodising it is not - nor is it a patch on proper anodising, but it's OK
for some uses.

Such as?

Not challenging, just interested!

Mary

--
Skipweasel
Pay no attention to that man behind the curtain.

Aluminium
 

The message
from "Mary Fisher" contains these words:

Anodising it is not - nor is it a patch on proper anodising, but it's OK
for some uses.

Such as?

Not challenging, just interested!

I used it for a bit of alloy that covered a hole where something else
had previously been - just to stop it taking up fingermarks so badly. It
wasn't a frequently used bit.

--
Skipweasel
Pay no attention to that man behind the curtain.

Aluminium
 

"Guy King" wrote in message
...
The message
from "Mary Fisher" contains these words:

Anodising it is not - nor is it a patch on proper anodising, but it's
OK
for some uses.

Such as?

Not challenging, just interested!

I used it for a bit of alloy that covered a hole where something else
had previously been - just to stop it taking up fingermarks so badly. It
wasn't a frequently used bit.

Oh ... thanks

Mary

--
Skipweasel
Pay no attention to that man behind the curtain.

Aluminium
 

In article ,
Tony Williams wrote:
Radiospares used to do an aluminium labelling system
(was it Copyphot?) where the final stage was to immerse
the label in a hot solution of some magic salts that
chemically grew the protective oxide film.

I've got an RS aluminium 'printing' system, but it starts out with
specially coated anodised ally. You expose the coated sheet to UV via a
mask and then dye the parts needed in a variety of colours.

--
*Avoid clichés like the plague. (They're old hat.) *

Dave Plowman London SW
To e-mail, change noise into sound.