More on stainless threads in aluminum --
c) If you really want to do it right put Nitronic 60 helicoils in all your
threaded aluminum holes along with some kind of thread lubricant or at least
a sealant to keep salt moisture out. 2 to 3 times the price of regular
helicoils. Google: Olander, Sunnyvale, CA and call them for a quote. All
common coarse thread sizes, a few fine threads and a good assortment of
metric. They are the source of these things for the semiconductor equipment
industry in CA. 10-12 years ago when I worked at Applied Materials I was
one of the instigators of this thing leading to the Helicoil folks
developing the Nitronic 60 product to solve the horrible problens we were
having with breaking stainless steel screws in vacuum chambers whenever
service was needed. In that application you can't use any kind of thread
lubricant because of contamination issues.
On the salt I think the problem starts when a little salt and moisture gets
into the threads between the stainless and the aluminum and turns it into a
miniature battery. Once the corrosion byproducts of the chemical reaction
expand into the thread clearances they tighten up everything. Then when you
go to take it apart the sliding loads between aluminum and stainless create
galling and siezure.
There's more interesting stuff to the Nitronic 60 story if anyone's
interested.
Ed Weldon
----- Original Message -----
From: "drmayf" <drmayf@mayfco.com>
To: "LSR" <land-speed@autox.team.net>
Sent: Wednesday, March 12, 2008 5:37 PM
Subject: [Land-speed] Anti Seize Question
> Two questions: a) is it necessary to use a thread anti seize when using
> stainless steel bolts into aluminum, b) if yes, then what is the
> preferred anti seize of choice? I have a nickle based high temp
> antiseize and a copper based version (named, by the way, never seize). I
> have, however, heard that milk of magnesia also works.
> mayf
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