Machining Tips
Gauging Plain Cylindrical
GAUGING: PLAIN CYLINDRICAL “PIN” GAUGES GO-NOT GO plain cylindrical gauges are used to check plain holes to ensure the holes are within tolerance. If the GO member is long enough to check the entire depth of the hole, it is also checking for straightness from top to bottom. Special design…
Interrupted Thread Pipe Taps
THREADING; INTERRUPTED THREAD PIPE TAPS Creating internal pipe threads offers many challenges. One challenge is the fact that when the tap reverses to exit, the tap must back up over the raised cut chips still in the lands and flutes that it just created. Space for those stored chips is…
Reaming Flutes
Reamer flute choices vary from straight flutes to flutes having a right hand spiral (RHS) or left hand spiral (LHS) orientation. For all practical purposes, they are all right hand cut (RHC) regardless of flute spiral direction. There are some guidelines however as to when Straight, RHS or LHS flutes…
H Limits and Classes of Thread
We discussed selecting the recommended “standard” H Limit for the various classes, 2B, 3B, etc. However, there are situations when larger or smaller H limits would be more appropriate. Larger H limits: The primary reason for using larger H limits is for plated or heat-treated parts. In both cases the…
Thread Milling Basics
THREAD MILL CHECKLIST: Consistent, predictable production even in exotic and hardened materials up to 62 Rc Control thread size to within 0.0001 Solid carbide thread mills are available to produce threads as small as #2-56 Full threads to within one pitch of a shoulder or bottom of a hole Will…
Selection Course and Fine Threads
Coarse Threads Coarse threads are commonly used where rapid assembly or disassembly is required. If corrosion or damage from handling or use is likely. They allow for easier starting with less cross threading. In relatively low strength materials such as cast iron, aluminum, magnesium, brass, bronze, and plastic, coarse threads…
Thread Mill Diameters
SELECTING THREAD MILL DIAMETERS When producing internal threads, selecting the right thread mill diameter insures it will operate efficiently. Thread mills are usually offered in several cutting diameters for a given threads per inch. Smaller diameters are used for small thread sizes, such as 3/8-16 NC. A larger tool diameter…
Acme Threading
The uses of Acme Threads usually involve special designs requiring individual consideration. Each tapping job becomes a minor engineering project of its own. The inherent exactness in application of Acme taps makes close coordination between manufacturer and user particularly important. An example of an Acme Thread application may be aircraft…
Erie Industrial Supply Company