The force on the cable stops creates a shearing force on the screws, so even though there are only a few threads engaged the screws will add plenty of strength to the setup.

JB Weld states their product has tensile strength of 2800 PSI, the 3 gang cable stops have about an inch of surface area, plus the 2 screws, my right hand has a grip strength of 165 pounds, the mechanical advantage of the brake lever will increase this force by a factor of, 10? So tension on the brake cable could be up to 1650 pounds if I pull the lever with all the force I can muster in my right hand, but I will never do that as the rear tire will be skidding long before I get anywhere to exerting the full grip strength of my right hand. So, assuming the screws do nothing, the JB Weld still has plenty of over head to deal with the expected forces, the screws are "belt and suspenders". The screws are 4-40 size. I will remove the paint under the cable stops with a dremel before I JB Weld them on so the glue will be metal to metal.

There are currently 7 cable guides and clips on my Raleigh Sprite, they are dull kind of gross looking galvanized steel, they will be replaced with 4 satin black cable stops which will look much better IMO.

I also need to add some stops to my Hercules 3 speed as it now has a 5 speed hub in the back and I need cable stops for the new cable on it that shifts the NDS side of the hub, that bike is semigloss black, so these home made flameless cable stops will be right at home there.