In actual practice, threads made a smaller major diameter the nominal size. make 1/4" bolt, start a rod least .005" smaller the nominal size, .250". depends the percentage thread want. with dies, you start a .250" die will be trouble, tight the die.
Rod Size for Die Threading: Calculator Menu: Thread Specification: Examples: #10-32 10-32 Numbered machine screw thread (#1 #12) 1/4-20 1/4"-20 .25-20 . Reducing size a rod want thread a die it easier start die,
The depth thread for 60 degree threads, the metric system, to subtract thread "pitch" the outer diameter. a #8 screw, "tap drill" size the major diameter (0.164') the pitch, 1/32, 0.03125" 0.13275".
I found site a calculator size rod for die threading. Rod Size for Die Threading . accessories bench top machinists. littlemachineshop.com use need provide thread diameter pitch. have it and worked well. edited: 9, 2024. Reactions: Mercurial Jim DuBois. J. Jerry Kieffer .
May it 0.001 0.002 undersize - fine. will foot long sections 1/2 dia rod turn down. good die have problem cutting thread a rod 0.500" dia. have has problem running 1/4-20, 5/16-18, 5/16-24, 3/8-16 any die a full size rod.
I find amazing number tables tap drill size thread tap. I can't find a table rod size thread size. For example, suppose wanted make 1/4-20 thread the of piece metal plastic rod. 1/4" rod to to too big my 1/4-20 die.
So 5/16-18 rethreading die 1/2" the flats. are to re-form damaged threads bolts, cannot cut threads. hex dies are standard die size, 1" the flats, for cutting threads solid bar. Dies for cutting threads be solid adjustable. Hex dies always solid.
If die has cut flanks root the thread, not crown, cutting less difficult. you 3/16" rod 4.76 mm you'll significantly smaller that, not smaller the minor diameter M5x0.8 (4.13mm) M5x0.5 (4.46mm) - you have reduced thread height, thus reduced strength.
Using nut thread measuring wires tell when have cut thread deep enough. tap/drill chart Ed posted tell the size hole need drill order accept particular thread diameter pitch. size the hole be varied set amount engagement.
Just fun tried smallest die, 2-56, the factory push rod it sorta screwed ok. UN calculator suggested says 2-56 thread requires major diameter from .0854 .0813. only die size comes close .047 0-80 .0595 .0562. I curious know thread .047 factory rods have. am .