Why thread relief

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Students Click Here. On an external thread with the relief groove at the root diameter it shouldn't be any weaker as this already the maximum diameter strength can be calculated from. Bobw , Ray Behner liked this post. I guess we need to see what Claya means by thread relief. There are several different types. I love thread reliefs, it's a nice little area that I look forward to when single point manual threading.

It's also done to create a "notch" engineering term for a weak point , in a place of your choosing. That way a bunch of screws will fail in the same place and under somewhat the same load with unknown force vectors. Even with the small radius on the threading tool you would accomplish the task of "proofing" the design and could rely on the parts to perform as desired.

If I think what the Op is asking about, the tool steel hardening texts call for a full relief, as it a place for cracks to form during heat treat.

Originally Posted by claya. With limited time threading on a lathe, is there a set rule on size and depth of the relief related to diameter and pitch of thread. Originally Posted by majohnson.

Originally Posted by jrmach. Bobw liked this post. With metric ISO threads you have a tolerance to the clearance groove diameter, not a spoken-out measure. Re: How to thread with no thread relief Post by Capt. Threading to a hard shoulder should be practiced. Disengaging the split nut and retracting the cross slide is the way its done. I like to do this at high speed when a novice is present just for the reaction. You have a option of starting at the shoulder with the tool upside down and run it in reverse out to the muzzle.

The relief can be cut in advance or after. Click on photo for larger view. Last edited by Capt. The only reason after years the government now wants to disarm you is they intend to do something you would shoot them for!

Its better IMO to have the pieces that are being connected to mate on square faces. Re: How to thread with no thread relief Post by superstriker90 » Tue Jan 01, am I'm not a gunsmith, but I am a machinist.

Its tricky I run very slow rpm's when doing this but you can zero an indicator on the way of the lathe where you want the thread to stop, start thread normally, when it hits zero on the indicator, quickly back the tool away from the part while shifting machine into reverse.

Never dis-engage half nut and allow lathe carrige to return to its starting point. This way is a must on some lathes ecspecially metric threads. Do you start your female threads with a little chamfer in the hole to ease mating?