G-Wizard Machinist's Calculator: Threads
The G-Wizard Threads
page provides handy reference material on threads of various kinds.
This page provides
information on Unified and ISO Metric threads. To use the page, begin
by selecting a Family, Size, and thread Class from the dropdowns on the
top left part of the page. You'll see tapping drill recommendations directly
below for those threads (assuming they're not too big that there won't
be a tap/drill combination). Note that cutting taps require different
recommended hole sizes than form taps.
Over on the right
is a stylized drawing of the thread with dimensions. You can select either
the Internal or External version.
For cutting threads
on a lathe, the thread depth section between Family/Size/Class and Tapping
Drill is important. It tells you for various thread categories how deeply
to plunge the tool to cut the thread. For example, if you are using a
sharp-pointed 60 degree "V" tool, use the "Sharp V-Thread
Depth." If you have a UN form tool with the proper radius at the
end, use the UN or UNR (for external threads) depths.
threads are covered by the "Pipe" tab of the Threads page. To
select a thread, first choose the Family and then choose the Size from
the dropdowns in the top left corner. The correct tap drill and tapping
depth will be presented below. Note that this is the tap drill for a non-reamed
hole. If you ream with a pipe reamer, a different tap drill is called
for. That recommendation will be added to a later version of G-Wizard.
On the right is
a stylized drawing of the internal and external threads with dimensions
for the various features. Since National Pipe threads are tapered, the
are pitch diameters taken against a number of significant locations along
the thread per the spec.
How about help with all those little details, like Fastener dimensions, drill charts, Ohm's law, and a bunch more in G-Wizard's Quick Reference tool?