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Josip
11-12-2006, 06:48 PM
Hi, all :)

Please I need some help about screws.
What means 2 B.A. x 3/4" LG Socket cap Tuflok coated screw

Some link, drawing....

Best regards, Josip :)

hiitsme
11-12-2006, 06:58 PM
http://www.engineerlive.com/european-design-engineer/instrumentation-electronics/page_2/2737/screw-enhances-productivity.thtml ---- tuflok

http://www.gewinde-normen.de/en/index.html ----- thread standards

http://www.accuratescrew.com/info/SocketRef.htm
In this last one under point 14 there is something about LG

Josip
11-12-2006, 07:39 PM
Hi, Hiitsme :)


http://www.engineerlive.com/european-design-engineer/instrumentation-electronics/page_2/2737/screw-enhances-productivity.thtml ---- tuflok

http://www.gewinde-normen.de/en/index.html ----- thread standards

http://www.accuratescrew.com/info/SocketRef.htm
In this last one under point 14 there is something about LG

Thanks for links, but for me the most important is 2 B.A. ... is that related to class, material, size, or...?

Need also some info about W.S.I No. 27 Class 2 and W.S.I No. 136 related to tightening torque...

Best regards, Josip :)

US Iceman
11-12-2006, 07:56 PM
Hi Josip,


http://en.wikipedia.org/wiki/Screw



British Association screw threads (BA)
A later standard established in the United Kingdom (http://en.wikipedia.org/wiki/United_Kingdom) was the BA system (http://en.wikipedia.org/wiki/British_Association_screw_threads), named after the British Association for Advancement of Science. Screws were described as "2BA", "4BA" etc., the odd numbers being rarely used. While not related to ISO metric screws, the sizes were actually defined in metric terms, a 0BA thread having a 1 mm pitch. These are still the most common threads in some niche applications. Certain types of fine machinery, such as moving-coil meters, tend to have BA threads wherever they are manufactured.


Here is another link that tells the whole story...
http://en.wikipedia.org/wiki/British_Association_screw_threads

It looks like the 2BA just tells you the the thread pitch and size.

Hope that helps;)

chemi-cool
11-12-2006, 08:34 PM
I didn't know that there is a European standard for screwing:D


Chemi:)

Josip
12-12-2006, 01:15 AM
Hi, US Iceman :)




It looks like the 2BA just tells you the the thread pitch and size.

Hope that helps;)

Thanks, yes it helps, but nothing about material, pity;)


Hi, Chemi :)


I didn't know that there is a European standard for screwing
Chemi

But now, you find out, some standards always exist:)

Best regards, Josip :)

hiitsme
12-12-2006, 06:53 PM
I didn't know that there is a European standard for screwing:D


Chemi:)

Here you are not able to find excuses to the miss...:-D

hiitsme
12-12-2006, 06:55 PM
Hi Josip,

this 2BA thing....

Doesn't it mean simply 2 pieces of screws which are BA standard????

Josip
12-12-2006, 08:56 PM
Hi, Hiitsme :)


Hi Josip,

this 2BA thing....

Doesn't it mean simply 2 pieces of screws which are BA standard????

No :) , I need 8 pcs (in text is 4+4 2B.A.)

Best regards, Josip :)

Electrocoolman
13-12-2006, 01:46 AM
Hi Josip,

B.A. stands for British Association thread form.

They range in size from 0 BA (the largest) which is about the same size as a M6, to I think about a 19 BA which is extremely small. The normal sizes are the EVEN ones 0,2,4,6,8,10,12. They used to be used alot for electrical equipment....still come across them in UK, but metric taking over.

2 BA is very similar to M5 and the 10-32 UNF. I think they will all thread in each other to a degree (some tight, some loose)

The material is not dictated to by the BA....you can get them in Steel and also in Brass. Normally have slotted heads.

The 3/4" LG would refer to the length (19mm). The Socket cap is the Head type which would be a recessed Hex (i.e Allen Key) probably with a knurled edge. I expect these to be Steel with a blackened oxide finish.

Hope this helps. More info on google.

US Iceman
13-12-2006, 02:37 AM
I expect these to be Steel with a blackened oxide finish.


Are these then considered to be heat treated for higher strength?

Based on your description this sounds a lot like the tiny bolts used in safety heads on large recip compressors..

Electrocoolman
13-12-2006, 09:40 AM
Hi US Iceman,
Yes the black oxide finish screws are heat treated HT steel,.......but currently I cannot find any listed in a BA thread, but that does not mean that they aren't available.

Josip
17-12-2006, 09:42 PM
Hi, all :)

Found this on the net;)

Nothing about material but I believe any material we need we can use for.

Best regards, Josip :)

Andy P
18-12-2006, 12:00 AM
Dear Josip,

I think you got all the answers already - all I can add is that BA threads are not much used these days, except in modelmaking and other hobbies. They are pretty small - like the screws that hold the cover plate onto an electrical socket. The LG reference I think was just an abbreviation for "long" - for example 2BA x 6LG is a 2BA thread 6mm long. 2BA only tells you the screw diameter and thread form.

cheers

Andy P