degrees of screw stainless steel
 

In yet another visit to the market place to get
bolts I read the text on the M4x10 socket screw
bag and they come in

stainless steel A4, or S/S
electro-galvanized
galvanized
zink plated

Electro-galvanized, is that a method to get it
galvanized or is it indicative of
better protection?

Zink plated I suppose is the worst - is it the
equivalent of applying zink spray after
removing rust from an automobile body?

Also these screws come in small packs - the
smallest only ten pieces a bag! And even the
S/Ss aren't that expensive. So why would anyone
settle for worse? Or are there advantages with
the galvanized and/or zink plated stuff in
certain conditions?

/the hairdresser

--
underground experts united
http://user.it.uu.se/~embe8573

degrees of screw stainless steel
 

On 6/9/2017 5:27 PM, Emanuel Berg wrote:
In yet another visit to the market place to get
bolts I read the text on the M4x10 socket screw
bag and they come in

stainless steel A4, or S/S
electro-galvanized
galvanized
zink plated

Electro-galvanized, is that a method to get it
galvanized or is it indicative of
better protection?

Zink plated I suppose is the worst - is it the
equivalent of applying zink spray after
removing rust from an automobile body?

Also these screws come in small packs - the
smallest only ten pieces a bag! And even the
S/Ss aren't that expensive. So why would anyone
settle for worse? Or are there advantages with
the galvanized and/or zink plated stuff in
certain conditions?

/the hairdresser

where are you buying these things exactly? (what country?) I don't
recall ever seeing zinc-plated stainless bolts, tho I suppose I haven't
seen everything.

For non-marine uses--stainless tends to gall easily so the purpose of a
coating is usually just to prevent the threads from getting sticky with
repeated insertion/removal.

In the US, normal stainless bolts are mostly 304 and
extra-corrosion-resistant (marine-grade) ones are 316:
https://en.wikipedia.org/wiki/Stainless_steel

Chrome-plated bolts look a bit nicer than the plain-stainless (no
finish), if you wanted silver shiny bolts.

coatings are plain, oxide or chrome.
mcmaster (USA) also shows silver-plated ones, but they're rather
expensive and I've never seen them used for anything IRL.

degrees of screw stainless steel
 

DougC wrote:

where are you buying these things exactly?
(what country?)

Sweden. The shop is "Clas Ohlson" which also
has shops in Dubai, Finland, Germany, Norway
and the UK. The range varies, I suppose.

The best thing about the shop here is that it
is located in the very city center. All other
shops (Biltema, Bauhaus, etc.) are in the
industrial areas. It is very close by car and
even by bike but I still don't like to go
there, it feels half the day is spent doing it,
and a lot of blue-collar people do it
*every day*, sometimes I think as an excuse not
to do actual work.

I don't recall ever seeing zinc-plated
stainless bolts

It just says zinc plated if that matters.
The galvanized doesn't say stainless either,
just either galvanized or electro-galvanized.
The stainless says "Stainless steel A4" and
"S/S".

--
underground experts united
http://user.it.uu.se/~embe8573

degrees of screw stainless steel
 

On 6/9/2017 6:02 PM, DougC wrote:
On 6/9/2017 5:27 PM, Emanuel Berg wrote:
In yet another visit to the market place to get
bolts I read the text on the M4x10 socket screw
bag and they come in

stainless steel A4, or S/S
electro-galvanized
galvanized
zink plated

Electro-galvanized, is that a method to get it
galvanized or is it indicative of
better protection?

Zink plated I suppose is the worst - is it the
equivalent of applying zink spray after
removing rust from an automobile body?

Also these screws come in small packs - the
smallest only ten pieces a bag! And even the
S/Ss aren't that expensive. So why would anyone
settle for worse? Or are there advantages with
the galvanized and/or zink plated stuff in
certain conditions?

/the hairdresser

where are you buying these things exactly? (what country?) I
don't recall ever seeing zinc-plated stainless bolts, tho I
suppose I haven't seen everything.

For non-marine uses--stainless tends to gall easily so the
purpose of a coating is usually just to prevent the threads
from getting sticky with repeated insertion/removal.

In the US, normal stainless bolts are mostly 304 and
extra-corrosion-resistant (marine-grade) ones are 316:
https://en.wikipedia.org/wiki/Stainless_steel

Chrome-plated bolts look a bit nicer than the
plain-stainless (no finish), if you wanted silver shiny bolts.

coatings are plain, oxide or chrome.
mcmaster (USA) also shows silver-plated ones, but they're
rather expensive and I've never seen them used for anything
IRL.



Used to see silver plate for electrical connector screws but
I haven't seen one in many years.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

degrees of screw stainless steel
 

The socket screws are

DIN 912 / ISO 4762 Socket Cap Screw A2/A4 Stainless Steel

and the washers are

DIN 125 / ISO 7089, 7090 Flat Washer A2/A4 Stainless

It says they are A4 on the bags.

http://fullerfasteners.com/products/...rew-stainless/
http://fullerfasteners.com/products/...her-stainless/

--
underground experts united
http://user.it.uu.se/~embe8573

degrees of screw stainless steel
 

Silver tarnishes ?

For bicycle use go with grade 5

5 is hard strong steel somewhat rust resistant..

Coat with thinned linseed

Hardware store SS maybe grade 2.5.

Go to the industrial era.

degrees of screw stainless steel
 

Emanuel Berg wrote:

The socket screws are

DIN 912 / ISO 4762 Socket Cap Screw A2/A4Â*Stainless Steel

and the washers are

DIN 125 / ISO 7089, 7090 Flat Washer A2/A4Â*Stainless

I have a German Heyco double ended spanner (10
and 13 mm) which is DIN 895. Wow, what does it
all mean? Some German system of
standardization...

--
underground experts united
http://user.it.uu.se/~embe8573

degrees of screw stainless steel
 

Go to the industrial era.

Ha! Of course, it is unavoidable sometimes.
Some stuff isn't available elsewhere. It is not
so industrial anymore BTW. De-industrialized
rather. But many of the hardware stores are
located there and their profits seem not that
bothered by the decay...

--
underground experts united
http://user.it.uu.se/~embe8573

degrees of screw stainless steel
 

On Fri, 9 Jun 2017 18:02:30 -0500, DougC
wrote:
In the US, normal stainless bolts are mostly 304 and
extra-corrosion-resistant (marine-grade) ones are 316:
https://en.wikipedia.org/wiki/Stainless_steel

A little more on stainless:

A2 is the same as 304.
A4 is the same as 316 and contains molybdenum and more nickel and
nitrogen making it stronger and more resistant to corrosion.

You can easily tell the difference. A2 is slightly magnetic, while A4
is non-magnetic:
https://www.youtube.com/watch?v=mbbXvvpoLCo

Stainless fasteners are normally NOT coated because stainless is
protected by a thin chromium oxide layer that forms on the surface.

If this is for your bicycle, either stainless type will work. I would
not recommend hot dip galvanized (ugly and too thick), electroplated
zinc (too thin and rusts where scratched), or chrome plating (looks
good until it rusts) fasteners. I'm undecided on bright chrome
plating, which seems to survive fairly well. However, at the small
differential in cost, stainless is still the best.



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

degrees of screw stainless steel
 

On Sat, 10 Jun 2017 00:27:56 +0200, Emanuel Berg
wrote:

In yet another visit to the market place to get
bolts I read the text on the M4x10 socket screw
bag and they come in

stainless steel A4, or S/S
electro-galvanized
galvanized
zink plated

Electro-galvanized, is that a method to get it
galvanized or is it indicative of
better protection?

Zink plated I suppose is the worst - is it the
equivalent of applying zink spray after
removing rust from an automobile body?

Also these screws come in small packs - the
smallest only ten pieces a bag! And even the
S/Ss aren't that expensive. So why would anyone
settle for worse? Or are there advantages with
the galvanized and/or zink plated stuff in
certain conditions?

/the hairdresser

Galvanizing is the coating of steel (usually) with zinc. Two common
methods are by "hot dip", immersing the object in a vat of molten
zinc, and plating which is an electrical-chemical method of depositing
zinc onto a part. Generally speaking, hot-dip results in the thickest
coating.

My own solution is to use only stainless bolts in the smaller sizes,
say up to 6mm...
--
Cheers,

John B.