I think machining to contact both surfaces, with contact being on the face first, then on the inner surface, adds to the rigidity of the joint. I think the ultimate would to have a 30 degree seat at both the face and the inner seat but this would be a little difficult to achieve and would require special gauging. I base this on fitting I did to stop some hydraulic cylinder rods from breaking at the shoulder where the piston contacted. The piston was eight inches in diameter and threaded onto a three and a half inch rod with a two and a half inch tenon. I used a 45 degree seat at the shoulder and the breaking was a thing of the past.
Anyway, I don't think it hurts to contact at both ends of the thread. I'm less certain there is any point in seating on the inner surface if a nut is used.
Any time I have the opportunity to utilize an internal shoulder, I do so, but I always seat on the receiver ring first. When the barrel is tightened up, it is obvious when the inner surface contacts; the barrel won't turn anymore.
That reaming is a little homely; I think the reamer could use a touch-up. WH
Anyway, I don't think it hurts to contact at both ends of the thread. I'm less certain there is any point in seating on the inner surface if a nut is used.
Any time I have the opportunity to utilize an internal shoulder, I do so, but I always seat on the receiver ring first. When the barrel is tightened up, it is obvious when the inner surface contacts; the barrel won't turn anymore.
That reaming is a little homely; I think the reamer could use a touch-up. WH
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