Machine Tap JIS B-4430 Form C 35° Spiral Flute HSSE - Rc (BSPT) 1/8 x 28

• for general use
• free-machining materials up to 900 N/mm²
• unalloyed and low-alloy steels
• for blind holes

Process: manual or assisted drive depending on your tool holder and machine setup. Use: thread cutting, thread recutting and thread cleaning depending on the thread condition.

Note Check that the workpiece, prepared hole and fitting match Rc (BSPT) 1/8 x 28; with a tapered pipe thread, alignment and working depth directly influence the quality of the assembly.

• HSSE cutting material for higher wear resistance than simpler high-speed steels in suitable industrial use
• Rc (BSPT) 1/8 x 28 according to ISO 7-1 for tapered pipe-thread connections
• 35° spiral flutes help guide chips out of blind holes
• technical drilling and tool-dimension data support safer process preparation
• suitable for maintenance, mechanical engineering, industrial assembly and threaded pipe connections

• hole preparation and alignment must be controlled carefully, because a poorly guided tapered thread can impair assembly quality; use the specified tapping drill diameter and inspect the workpiece before tapping

1. Identify the ISO 7-1 thread standard, thread direction and hole type before preparing the workpiece.
2. Select a holder suited to your setup and secure the workpiece so it cannot move during machining.
3. Prepare the hole according to the product data and deburr the entry cleanly.
4. Present the tap on the hole axis and visually confirm that it starts without tilt.
5. Lubricate according to the material and start cutting with steady feed without forcing the first threads.
6. Continue in a controlled motion so chips can move according to the tool geometry.
7. Reverse the motion smoothly when the planned travel is reached and withdraw the tool without striking the cutting edges.
8. Clean the thread and check the assembly with the matching component or a suitable inspection method.
9. After use, remove chips, dry the tool and store the tap separately from parts that could damage the cutting edges.

• 1 piece Machine Tap JIS B-4430 Form C 35° Spiral Flute HSSE - Rc (BSPT) 1/8 x 28

• Product type: machine tap
• Cutting material: HSSE
• Dimensional standard: JIS B-4430
• Thread system: Rc (BSPT)
• Size: 1/8 x 28
• Thread standard: ISO 7-1
• Chamfer form: C
• Flute form: R35, 35° spiral flute
• Hole type: blind hole
• Thread direction: right-hand thread
• Tolerance: medium
• Hole identification: SALO
• Tapping drill diameter: 8.2 mm
• Overall length L1: 55 mm
• Thread length L2: 19 mm
• Shank diameter D2: 8 mm
• Square k: 6 mm

What does Rc (BSPT) mean for this machine tap?
Rc (BSPT) designates a tapered internal pipe thread according to ISO 7-1. For this product, the stated size is 1/8 x 28; it must match the fitting, thread system and component specification.

Which hole type is this form intended for?
Form C 35° Spiral Flute should be selected when the process requires controlled depth and chip evacuation in blind holes.

Why does the description specify HSSE?
The description has been corrected to HSSE for this product family. HSSE is cobalt-alloyed high-speed steel used when edge stability and wear resistance are important in suitable applications.

Can you use this tap to recut an existing thread?
Yes, if the size, thread standard and condition of the existing thread match. Clean the area first, check alignment and do not force the tool if it does not enter cleanly.

What should you check before tapping?
Check the Rc (BSPT) thread standard, hole type, lubrication, work material and compatibility with the intended fitting. With tapered pipe threads, inaccurate preparation becomes noticeable quickly during assembly.

What is the practical difference between the 975 and 977 series?
The 975 series uses Form B with straight flutes for through holes. The 977 series uses Form C 35° Spiral Flute and is suitable for blind holes.

Where can you find more information about the range?
You can consult the relevant catalog document here: VD 23 catalog as PDF.