[MDairheads] Exhaust Port Thread Question

[Jim Wilson]

disclaimer:
NOT for so called guru's to read

i show here my set of thread chaser files ... there are 8 sizes per file.
 2  are USA  1 is whitworth because of my many brit machines...

know that different threads have different 'pitches'  and # of thread Per
Inch.        so using a 3 sided hardware store hand file has a different
angle than what you may need.      some file kits have 8-10 different
angled files available so those are easy to buy and use        * slowly and
carefully.*


another old machinists trick is to use/ make  a chaser die.    this can
simply be made of an exhaust nut  [yeah    gotta buy a nut to clean the
threads where you cut  4 or 5  SLOTS are cut 90º   into an 1/8 or 3/16''
into the threads.    this  semi sharp edge makes a ' cutter' at each groove
you made.    i use a hand 4'' grinder to make my grooves which are cut
clear thru the chaser nut,   cut into the threads.   Clean up the now cut
chaser threads inside so no burrs are present,  before you attempt to chase
the threads on the head using oil as a lubricant.   advance the thread
chaser a little then back-off a tad.
just the same process you use when threading with a tap or die.
https://www.youtube.com/watch?v=r6Ijd9o-C10           turn, back off
....... turn  ,,  ,,  back off  repeat.



i'll show you a couple way to make the chaser.
again   do this only as a last resort before handing it off to get a
professional job done.  you just may surprise your self and save the
threads.

as mentioned use an anti seize on the nuts.  copper is good   ... nickel is
better  w/ a higher heat range.

FHBCQO2GB0JQOSE.LARGE.jpg
<https://cdn.instructables.com/FHB/CQO2/GB0JQOSE/FHBCQO2GB0JQOSE.LARGE.jpg>
FU4RSJOGSUT3D1A.LARGE.jpg
<https://cdn.instructables.com/FU4/RSJO/GSUT3D1A/FU4RSJOGSUT3D1A.LARGE.jpg>

homemade-rear-hub-thread-chaser.jpeg
<http://www.homemadetools.net/uploads/37218/homemade-rear-hub-thread-chaser.jpeg>

kinda   cut  like this photo
41SQJ7XcGRL.jpg
<https://images-na.ssl-images-amazon.com/images/I/41SQJ7XcGRL.jpg>

20170220_135737_zps6bleomfr.jpg
<http://i322.photobucket.com/albums/nn424/luftwaffe_birdman/20170220_135737_zps6bleomfr.jpg>


good luck and go slowly



-- 

          *   Jim   *

* the shortest distance between two points is .. well frankly  * …. *Boring*
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