Hi Harry It is very likely the thread you are trying to match is ¼ BSF which is 26 tpi, these are still quite easily obtained in the UK. Regards Brian ----- Original Message ----- From: "Harry Wade" <hww@xxxxxxxx> To: <modeleng@xxxxxxxxxxxxx> Sent: Wednesday, November 21, 2007 3:41 AM Subject: [modeleng] Mystery thread >I am presently converting a 14" Rockwell wood bandsaw for metal cutting and >I need to match the thread of a grubscrew (missing) for a David Brown >reduction gearbox, which I assume was made in the UK. The screw diameter >measures .216" and the pitch is between a 24 and 28tpi but it is neither a >24 nor 28. The .216" is dead-on for a US #12 machine screw but it isn't >that. Anyone have an idea what this thread might be? > Regards, > Harry > > 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. > > > -- > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.5.503 / Virus Database: 269.16.1/1140 - Release Date: > 19/11/2007 19:05 > > 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.