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Letter 32469
Melonite vs Tennifer on semi-auto pistol
slides
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Where would I find a Side by side comparison of Burlington's
Melonite Process and the German Tennifer Process? I am often involved
in arguments regarding the these two finishes on Smith & Wesson
and Walther forums. Both Companies produce a version of the same
Walther Designed 99 pistol (Walther Tennifer over Steel and Smith
amp;& Wesson Melonite over Stainless steel.) Because of the
success and reputation Tennifer gained after the Glock Pistols were
introduced to the U.S. market some years ago, Tennifer seems to have
gained the reputation of a indestructible miracle finish unable to be
duplicated in America. I say this attitude is wrong and American
finishers know just about as much about super hard firearms finishes
as the Germans on their best day. Smith & Wesson didn't just pull
Melonite out of a hat. The Engineers at Smith & Wesson knew that
Melonite over Stainless, was a pretty advanced finish for Firearms
slides. So help me out guys. I may be right. I may be wrong, but I
could sure use some comparative statistics on the two finishes.
Jim Davis
Hobbyist - Enid, Oklahoma
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Hi, Jim. Tennifer and Melonite are trade names for
firearm finishing processes that involve salt bath
nitriding. The heart of the matter is probably licensing
rights rather than technology. I do not have any special
inside information, but I believe that Glock will not let
the supplier of this finish license the Tennifer name to any
other firearms manufacturer; therefore, other firearms
manufacturers are using a similar finish but from other
chemical suppliers or under different names.
Historically, firearm parts were black oxided, which is
an oxidation process which is only a few millionths of an
inch thick, does not offer much corrosion resistance, and
doesn't alter the underlying steel. Salt bath nitriding is a
case hardening process that leaves a fairly thick, corrosion
resistant, hard surface.
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Ted Mooney, P.E.
finishing.com
Brick, New Jersey
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February 6, 2006
What happens to a Melonite pistol slide that later has to
be re-blued. Do the Melonite properties remain in the metal
or do they disappear? In other words, is it (the Melonite) a
permanent part of the metal. I have a Melonite slide that I
would like to refinish so I am curious. Thanks.
Richard Kay
- Port Washington, New York
February 7, 2006
There's no such thing as 'permanent', especially when
you're talking about a surface finishing process. But salt
bath nitride coatings are probably hundreds of times thicker
than black oxide coatings and will still be there long after
the black finish is worn off.
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Ted Mooney
finishing.com
Brick, New Jersey |
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August 16, 2006
From what I understand - Teniffer can't be applied in the US
because the EPA won't allow it.
I was a project manager for a manufacturing facility - and we wanted
"tennifer" like qualities applied to some steel parts - and after
tracking down the facilities in Europe that apply the tennifer finish
(it is not a Glock exclusive) - those companies told us they couldn't
set up shop in the US because the EPA wouldn't allow the teniffer
process to be done here.
So - that would make the "Melonite" process different - as it can be
done in the US. How different - I have no idea. More importantly - if
there is any *practical* difference between the finishes?? That is
the $64,000 dollar question...that I don't know the answer to.
Jones
- Odgen, Utah
August 16, 2006
I have seen a lot of postings to that effect on gun forums, Jones,
but I really don't think it's an EPA issue because salt bath
nitriding is very widely practiced in this country. I still believe
it's a licensing issue and that those shops may have been bending the
truth a wee bit.
I would suggest that anyone who is interested in this process may
wish to speak to Brian Radford of Kolene (a supporting sponsor of
finishing.com, located at
http://www.finishing.com/Equipment/kolene.shtml,
or at least review their paper on the QPQ process at
http://www.finishing.com/kolene/qpq/index.html.
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Ted Mooney
finishing.com
Brick, New Jersey |
September 12, 2007
MELONITE IS ANOTHER WORD FOR TENIFER. THEY ARE THE SAME EXACT
THING! YOU CAN DOUBLE CHECK MY ANSWER BY SIMPLY TYPING "MELONITE
ENCYCLOPEDIA" ON THE GOOGLE SEARCH AND BE ABLE TO LOOK IT UP YOURSELF
FOR VERIFICATION.
Christopher Deleon
- Palm Beach, Florida
September 11, 2007
Thanks, Christopher
At www.durferrit.com/en/unternehmen/firmengeschichte.htm, Houghton
Durferrit -- formerly part of DeGusa, but now a division of H.E.F. --
claims both trademarks and says they are the same thing. If they own
the tradenames as they claim, they are free to decide how the
processes are done, including whether they are identical or not, just
as Ford has been free to make a "Thunderbird" a 2-seat sports car, a
4-seat luxury car, or a 6-seat family sedan to suit changing times.
Similarly, the same page claims that the Tenifer and Melonite
process "has undergone continuous development with regard to its
regenerability and ecology". So neither is quite what it was in the
past.
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Ted Mooney
finishing.com
Brick, New Jersey |
September 27, 2007
The only difference in the "Tennifer" process and "Melonite" is
the brand name.
But the original German formulation for the "Tennifer" carbonitriding
salt bath used 60% sodium cyanide and cyanate and 40% potassium
cyanide and cyanate.... That's why the EPA wouldn't let anyone do it
here.
The process has to be cyanide free here.
As far as I can find out, some places in Europe are still using
cyanide salts.
Mmmmm....smell the vapor coming from that vat of molten sodium
cyani..i...... thud!
Edward Baltzer
- Birmingham, Alabama
September 27, 2007
Thanks, Edward, but can you quote an EPA reg that says this? I'm
not saying you are wrong, but I am saying that we've received
countless postings saying "the EPA doesn't allow . . ." that have
been in error.
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Ted Mooney
finishing.com
Brick, New Jersey |
October 14, 2007
The Tenifer process is not exclusive to Glock. In fact SAAB of
Sweden once used the same process for it's cam and crankshafts. The
main difference between the Tenifer and Melonite processes is a
matter of splitting hairs. I believe that it is simply an EPA issue,
in two seperate processes, each having the same end result.
Jeremy Shank
- Atlanta, Georgia
November 28, 2007
Okay, so if these two processes are the same, how come I've seen
Smith and Wesson firearms that are Melonite treated rust/corrode, but
Tennifer doesn't? A friend of mine has carried both guns concealed
and his Glock 26 never rusted, but his M&P 9 compact did? Through
practical experience, I have to disagree that they are the same. They
react differently when they are placed in the same environment.
Todd Heimann
- Cincinnati, Ohio
December 3, 2007
Just because they are the same finish doesn't mean they are
applied the same way. Company X might have done a bad job of applying
the product. Perhaps they had a bad batch of the product?
Levi Gresser
- Baltimore, Maryland
February 17, 2008
Thanks in advance,
My question regards the Melonite/tenifer debate and actually is quite
simple. My understanding of this salt nitriding acid bath process is
that it doesn't translate well to stainless alloys, that it actually
weakens their ability to withstand corrosion? Would this perhaps
explain why were seeing the S&W product developing oxidation?
Chris Edwards
- Roseville, Minnesota
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August 19, 2008
Just came across these questions regarding Melonite and
thought I would shed some light. As the former engineering
Manager of S & W I can tell you that we chose Melonite
for several reasons, one being durability and the other that
it could be used on both 4140 and 416 stainless. However, I
don't recommend it for the latter because it actually
removes some of the properties of the material, which
ultimately could allow for rust/corrosion.
The facility we selected is located in the Mid West (no
secret there) and let's not give Gaston Glock too much
credit, the tennifer finish has been used by the German
automotive industry for years, including BMW and
Mercedes.
I will give him credit for taking a very traditional
industry and introducing a great product using simplicity
and light weight materials (Original patents for many of
Glocks design were filed in the 40's, years ahead of its
time)
Hope this helps.
David Sargeant
- Coral Springs, Florida
December 31, 2008
David,
Like Crazy Einar I give Gaston Glock kudos because when he
put down his ideas for gun designs he didn't know anything
about it ... so he didn't have any preconceived and
"traditional" notions of what goes into it. Therefore he
looked around and added the best technology available to do
the best job.
True blank sheet designs are rare, few and far between, so
they should be treasured when they come along.
J. Michael Antoniewicz II
- Greensboro, North Carolina
February 2, 2009
Is anyone here familiar with austempered ductile iron
(ADI)? this process uses a salt-bath process, too. The
material is used for crankshafts, suspension parts and
whatnot--exposed to stresses not unlike guns. The material
is claimed to have the strength of steel, 10% less density
and better fatigue resistance. It's easier to machine than
steel. Is this used in any handgun, to anyone's knowledge?
Adam C. Sieracki
- Calgary, Alberta, Canada
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