Hello Jacques, You're measuring overall length. The length of a cap screw is typically from the shoulder to the end of the threads. I think the screw you're showing is the same length as John's.
Thanks, Barry - N4BUQ ----- Original Message ----- > From: "Jacques Fortin" <[email protected]> > To: "jkharvie" <[email protected]>, "Barry Scott" <[email protected]> > Cc: "R-390 Mailing List" <[email protected]> > Sent: Monday, July 15, 2024 12:31:00 PM > Subject: Re: [R-390] Bristol Clamp Screws > Barry and JK, the original screws for the "big knobs" clamps are 0.692 inches > long. > See attached picture. > But the ones I still have are "eaten" in their internal splines. > The other that are assembled in the clamps in my picture are (more available) > stainless hex ones. > Do not forget to have the small washer fitted in the clamp to prevent it to > turn > around when you try to tighten the screw(s). > > 73, Jacques, VE2JFE in Montreal > > -----Message d'origine----- > De : [email protected] <[email protected]> De la part > de > jkharvie via R-390 > Envoyé : 15 juillet 2024 12:03 > À : [email protected] > Cc : [email protected] > Objet : Re: [R-390] Bristol Clamp Screws > > > > This is the screw, lock washer and square nutThe distance from the end of the > screw to the socket head shoulder measures 0.508 inches Let me know if this > works as a replacement. > > > Sent from AOL on Android > > On Mon, Jul 15, 2024 at 11:38, Barry Scott<[email protected]> wrote: > ... > and it just occurred to me that the smaller clamps may have shorter screws. > The screws for the large knob clamps are 9/16" long. Is yours that long? > Thanks,Barry > > On Mon, Jul 15, 2024 at 10:30 AM jkharvie <[email protected]> wrote: > > Interesting! I wonder if we have a collection of observed defected and other > manufacturing irregularities.Yes, one screw surplus to my needs is yours, it > is > from a broken clamp that replaced with a split clamp configuration. Should be > the size you need.John (N3JKE) > > > > > Sent from AOL on Android > > On Mon, Jul 15, 2024 at 10:41, Barry Scott<[email protected]> wrote: > Looks like the front panel is about finished and turning my attention to > the knobs, escutcheon, and meter covers. > > When I first removed the two large knobs a couple of years ago, I could tell > one > of the clamp screws did not have the same spline-drive as the other one as the > socket was slightly larger than the other one. I thought someone had replaced > the spline-drive with a hex-drive but yesterday, I discovered that it is a > larger spline socket. Both are six-spline versions but one is a 0.096" > (Xcelite 99-66) and the other is a 0.111" (Xcelite 0.111"). > > From what I can tell, they're both #4-40 screws but one is just a few > thousandths larger in diameter (not large enough to be a #5 and possibly just > manufacturing tolerance differences). > > Also, one knob has the two ribs in it and the other doesn't. I didn't track > which one had which screw in it and I don't think that really matters. Most > likely, somewhere in a repair depot, a knob was installed from a radio from a > different manufacturer. > > I'd like for these both to have the same Bristol drive (the 99-66 0.096" > version) so as to match the screws from all the other knobs. Anyone know > where > I could get a proper socket-head screw for this? I know these are pretty rare > and likely the only place I'd find that is from another clamp/knob/radio but > thought I'd ask. > > Thanks, > Barry - N4BUQ > ______________________________________________________________ > R-390 mailing list > Home: http://mailman.qth.net/mailman/listinfo/r-390 > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > > > > ______________________________________________________________ > R-390 mailing list > Home: http://mailman.qth.net/mailman/listinfo/r-390 > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ R-390 mailing list Home: http://mailman.qth.net/mailman/listinfo/r-390 Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
