Professorwiz
Veteran
Location: Livonia, Michigan - USA
| windy62:
The diameters are the same, but the material would be smashed into itself (Forged) vs cut off. This creates a thread that is denser than standard. There are many good reasons for thread rolling these days and not many minus. The issues are, if your tapping you have to have a very accurate hole to start with, too much material and you'll break the tap, not enough and there's no threads, vs a cut tap you can have almost 2X the difference in size, example. If you have a M5 tap, the specs might call out a +-.002" tolerance for the hole size, vs on a cut tap you could be off by +-.005" and not see any difference. Another minus is that since it's cold forging itself, the finish isn't as shiny, yes some people really get annoyed that the threads don't have a shiny finish some times.
Plus side is no chips in the hole, specially if it's a bottom tap where you have to thread right to the bottom of a blind hole, and of course stronger threads.
Russ
Go that way really fast.. If something gets in your way.. TURN |
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