If 7Ba and 8Ba are either side of what it is, then I'd suspect it is a 3/32" diameter thread. For example, on Alan's page, there are some sewing machine threads about that size... http://www.alanstepney.info/page81.html What number of threads per inch is it? Yours, Rich. On Tue, 19 Dec 2006, Allen Messer wrote: > Perhaps an old Bassett-Lowke catalogue would shed some > light on the thread size? > > Al Messer > --- Alan Stepney <alan@xxxxxxxxxxxxxxxx> wrote: > >> There arent many threads in that size range. >> >> 7BA is 98 thou x 52.9tpi, and 8BA is 87 thou x 59.2 >> tpi. (Those all look >> more sensible in metric!) >> There was a pair of Whitworth instrument threads, of >> 90 thou and either 50 >> or 60 TPI, the Thyry upon which BA was based (but >> they are so close to BA >> that they can be ignored), plus a Loewenhertz thread >> and possibly another, >> but both the latter are used solely in watchmaking. >> >> >> Alan Stepney >> >> http://www.alanstepney.info >> Model Engineering & steam engine information pages >> ----- Original Message ----- >> From: <bede@xxxxxxx> >> To: <modeleng@xxxxxxxxxxxxx> >> Sent: Tuesday, December 19, 2006 1:53 AM >> Subject: [modeleng] BA/ME Thread Query >> >> >> >> Hi All, >> >> I'm fitting point rodding on my gauge 0 (live steam) >> layout and have >> some old but unused brass "forks" to connect the >> rodding to the bell >> cranks. The forked end connects to the bell crank >> with a split pin, and >> the other end is tapped to thread onto the end of >> the rodding. >> >> But I need to thread the ends of the rodding and >> can't figure out what >> the threads are on the forks- they seem to be >> somewhere between 7BA and >> 8BA. Both threads work after a fashion, the 7BA a >> tight fit and the 8BA >> on the loose side, but neither seems really right. >> And the smallest ME >> thread I know of is 1/8" x 40tpi, which is too big. >> Am I missing >> something here? These forks were mass produced by >> Bassett-Lowke, >> MilBro, etc, so must have been to a standard thread. >> >> Any thoughts? >> Thanks as always. >> >> Bede in balmy Brooklyn, NY >> >> MODEL ENGINEERING DISCUSSION LIST. >> >> To UNSUBSCRIBE from this list, send a blank email >> to, >> modeleng-request@xxxxxxxxxxxxx with the word >> "unsubscribe" in the subject line. >> > > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around > http://mail.yahoo.com > MODEL ENGINEERING DISCUSSION LIST. > > To UNSUBSCRIBE from this list, send a blank email to, > modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject > line. > MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.