STI (Helical Coil) Thread Plug Gauges
During thread building / re-building operation the tapped hole plays a major role and the accuracy of finished thread after the insert is installed completely depends on the accuracy of the tapped hole. Therefore determining its accuracy is very important. If the finished tapped hole is accurate, the installed insert will be within the required thread tolerance.
Rapi-Coil STI Thread Plug Gauges (Metric) give the correct and accurate parameter to gage a tapped hole prior to installing the Screw Thread Wire Insert.
Our Gauge handles and nibs are marked with the extreme product limits for the particular size and class of fit. For best results
the Gage should always be appropriately lubricated before gaging thoroughly cleaned tapped holes.
An installed Screw Thread Insert is not needed to be gaged as any gaged tapped hole will fit and wind the Insert most
perfectly and accurately.? After the insert is installed, the GO thread plug gauge may not enter freely. The insert will always
seat itself when the bolt or screw is installed and tightened.
Specification :
BS 4377-1991 for ISO Metric Threads.
Rapi-Coil STI Thread Plug Gages (metric) for checking the tapped hole are listed below. The complete gage includes the GO thread plug gage, the HI thread plug gage and the appropriately marked gage handle.
SIZES - Metrics
Complete Gage
Art. No.
Nominal Thread
Size - 6H
RCTPG2 M2 x 0.4 RCTPG22 M2.2 x 0.45 RCTPG25 M2.5 x 0.45 RCTPG3 M3 x 0.5 RCTPG35 M3.5 x 0.6 RCTPG4 M4 x 0.7 RCTPG5 M5 x 0.8 RCTPG6 M6 x 1 RCTPG7 M7 x 1 RCTPG8 M8 x 1.25 RCTPG10 M10 x 1.5 RCTPG12 M12 x 1.75 RCTPG14 M14 x 2 RCTPG16 M16 x 2 RCTPG18 M18 x 2.5 RCTPG20 M20 x 2.5 SIZES - Fine Metrics
Complete Gage
Art No.
Nominal Thread
Size - 6H
RCTPG8F M8 x 1 RCTPG10F M10 x 1 RCTPG10FA M10 x 1.25 RCTPG12F M12 x 1.25 RCTPG12FA M12 x 1.5 RCTPG14F M14 x 1.5 RCTPG16F M16 x 1.5 RCTPG18F M18 x 1.5 RCTPG20F M20 x 1.5
