Date:         Sun, 27 Feb 2000 08:24:13 -0500
Reply-To:     McComas_Glenn <mccomas@SHORE.INTERCOM.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         McComas_Glenn <mccomas@SHORE.INTERCOM.NET>
Subject:      broken exhaust stud
Comments: To: gbasey@LINK2000.NET

To: Gary {'80 westy (longing for the road)}

Some FLAPS guys may act like imbeciles....... others try to be helpful.  You
can save yourself some grief with the former by learning about metric
threads.  Most American iron has been assembled with metric fasteners since
~1980.  I cannot imagine a FLAPS without a cabinet full of metric threaded
fasteners.......  if you ask.  Take a sample with you when you go in.  If
you can tolerate pedantic paragraphs, read on--

A longer-term suggestion would be to go to someplace like Sears and look at
metric tap and die sets.  Maybe buy one if they go on sale.  Familiarize
yourself with the metric way of talking about threads -- it is different
from the American way.

American threaded fasteners [generally ¼" Outside Diameter and greater] are
characterized by OD and number of threads per inch.   Ask for a ¼-20 bolt,
put a 1" ruler along it, look at the little 'peaks' and you will count 20
threads in 1 inch.  Ask for a ¼-28 and count 28 threads per inch.  The ¼-20
is called 'national coarse' or NC.  Test: Why is ¼-28 called NF?
True/false: NFW should you use a ¼-28 nut on a ¼-20 bolt.

Now moving along to metric:  The OD is given in millimeters but the threads
are indicated by the number of millimeters from the peak of one thread to
the peak on the next thread, known as the pitch.  A common size in VW engine
sheet metal is
6mm OD, 1.00mm pitch...... or  6x1.00mm for short.  For exhaust studs on the
earlier Type 1 and 2 engines,  8x1.25mm would be common.  [Sorry, it's
raining now, my Vanagon is not indoors, and the coffee is toooo good.  I'll
let you take it from here.]

Hope this will help you
Glenn
Queenstown, Maryland