You want fine thread. The engagement, or amount of material 'gripping'
between bolt & stud, will be approx twice as much. Stronger and less
tendency to vibrate loose.



Gene Kearns wrote:
Silly statement. Please provide proof....

Well, that's what the ASCME handbook on threaded fasteners says.

http://www.boltscience.com/pages/glossary.htm

or a better exact quote from
http://www.fastenal.com/web/document...renceGuide.pdf
near the top of page 11
"Fine Thread... offers more resistance to loosening when subject to
vibration than does coarse thread."

Good call on not welding them. Bad call saying that my statements are
"silly" when it's just common sense and a little bit of familiarity with
this range of technical knowledge.

Regards
Doug King