Tapped Hole Distance

[dhensley]

I was wondering if there is a rule of thumb for the distance a tapped hole should be from an open end of a part. I want to use a 3/8" tapped hole but I am concerned about the distance between the thread and end of the part. Due to constraints I can only have the hole positioned 1/4" from the end of the part. Will this be enough or should I try to position it further away?

 

[Mandrake22]

Centerline of tapped hole to part edge:

(Nut flat width-bolt Ø)/2 x 1.5 + bolt Ø/2

Your example: (.5625-.375)/2 x 1.5 + .375/2= .328"

 

[site]

Distance from the end to bolt hole should be two or three mm minimum + half the across corner of the bolt head.

 

[smcadman]

Centerline of tapped hole to part edge:

(Nut flat width-bolt Ø)/2 x 1.5 + bolt Ø/2

Your example: (.5625-.375)/2 x 1.5 + .375/2= .328"

Mandrake, is this generally for all steels, or would this apply to aluminum also?

Flores

 

[Mandrake22]

smdadman,
The rule of thumb in my fine equation of course is the x1.5 factor. This, roughly, is the ratio of tensile strength of a typical hex nut to typical low carbon steel. You would have to adjust this value depending on your fastener material/grade or tapped material tensile strength.

 

[dhensley]

Thanks for the help. This is exactly what I was looking for.

Later,
Dennis