From: REMOVE_THISdwilkins@means.net (Don Wilkins)
Newsgroups: rec.crafts.metalworking
Subject: Re: The plating jar
Date: Wed, 30 Dec 1998 14:54:52 GMT

On 30 Dec 1998 06:51:30 GMT, "Don Foreman"
<foreman_don@htc.honeywell.com> wrote:

<zinc stuff snipped>

>I omitted mention of  nickel in original post because it was a bit off
>topic -- but the electroless nickel is REALLY NEAT.   The electric nickel
>is too, goes further -- but one must worry about getting into nicks and
>crannies.  The electroless stuff gets into every hole and right down into
>the roots of threads.  Only drawback is that it wants to run hot -- close
>to boiling -- so there's some time involved in heating up the soup.  But
>for small objects it's wonderful.  No worry about power supplies etc;  I
>hang the pieces to be plated on bits of thread from a stick, and they plate
>perfectly.

You probably are aware of it but others may not be.

Electroless nickel usually is produced using hypophosphite as the
reducing agent. The plate that you get is not nickel but is a
nickel-phosphorus compound. It is your choice whether you call it an
alloy, intermetallic compound, etc.

93% Ni-7% P is a typical composition. The coating is decorative,
chemically quite stable, and hard. You get good throwing power as long
as you have efficient stirring. Coverage is excellent so you don't get
corrosion from cracks and\or pinholes in the coating.

There was an extensive study of this process many years ago and
published in the Journal of the National Bureau of Standards.


>I use it on marine mechanisms with sliding contact where zinc would
>eventually wear away.  The nickel is pretty tough.  Not as hard as chrome,
>but chrome is fumerous and ventilating in Minnesota in December gets
>expensive.

How do you like that below zero stuff down there in the banana belt?
That global warming was good while it lasted.

>My shipment of stuff to plate nickel on aluminum arrived in Mnpls today
>according to UPS so I should see that tomorrow.  I'll post results if
>anyone is interested.  My interest in getting nickel onto aluminum is
>because you can plate about anything onto nickel.  I want to selectively
>plate copper to aluminum for a research apparatus.  I'll be particularly
>interested to see how well solder joints to the copper work out.

If this stuff is an electroless plating witches brew then the lattice
parameters will probably be different than nickel which could cause
problems for an electroplate to stick. The other reducing agent for
electroless nickel was a boron hydride. This produced a nickel-boron
coating.

You should be able to sneak into a library on the U of M campus if you
need additional info on the original research if Honeywell doesn't
have the journals. There was a lot of stuff on plating conditions. If
you are using a proprietary mixture (read premium price) you should be
able to get the information to make your own. We made our own and it
worked just fine. The lower melting point killed our application.

>BTW, I just discovered that ordinary  95-5 plumbing solder (95 tin 5
>antimony) sticks to aluminum quite nicely!  This tumble came from reading
>some material about indium-based solders -- which said that tin works well
>with aluminum. And so it does! I had the plating stuff on order before I
>discovered this, so it will be interesting to compare results.

From: REMOVE_THISdwilkins@means.net (Don Wilkins)
Newsgroups: rec.crafts.metalworking
Subject: Re: Nickel Plating
Date: Wed, 31 Mar 1999 13:12:33 GMT

On Tue, 30 Mar 1999 17:43:48 GMT, "Kurt Bjorn" <pyroware@flash.net>
wrote:

>I was wondering if anyone would care to compare electroless vs electrolytic
>nickel plating... specifically, ease of use, durability (especially under
>heat and vibration), and overall satisfaction.
>
>I have the Caswell catalogue, BTW, for anyone interested in home plating,
>this is the resource:
>www.caswellplating.com

Electroplated nickel is essentially pure nickel. Electroless nickel is
about 93% nickel 7% phosphorus when hypophosphite is used. Actually
there is a range of compositions depending on the experimental
conditions. The deposit can be much harder than pure nickel and AFAIK
does not have the stress that one finds in some electrodeposited
nickel. Corrosion resistance is also different.There are heat
treatments which will change the hardness, etc.

We looked at the electroless nickel for protecting high temperature
molybdenum turbine buckets. Never went into production.

There is also another procedure using a borate compound. In this case
the deposit contains boron. I do not recall the amount.

Much of the original work was done at the US National Bureau of
Standards. I have the references but it would be easier for me to
drive the 200 miles to a decent library than to root through my files.
I believe much of it was done in the 30s and 40s.

You can buy proprietary solutions but it is much cheaper to make your
own if you are going to do much electroless deposition.