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OSG Screw Thread Insert STI Tap: Spiral Point, 7/8"-9 UNC, H3 / 2B-3B, 3 Flute - Spiral-Point STI Taps
OSGSpiral-Point STI Taps

OSG Screw Thread Insert STI Tap: Spiral Point, 7/8"-9 UNC, H3 / 2B-3B, 3 Flute

The OSG Screw Thread Insert STI Tap is a spiral-point tap designed for threading holes to accept screw thread inserts. This 7/8"-9 UNC tap features an H3 / 2B-3B tolerance, 3 flutes, and a plug chamfer (MPN 12502100).

SKU 3G-OTH-287034

Brand
OSG
Item
Screw Thread Insert STI Tap: Spiral Point, 7/8"-9 UNC, H3 / 2B-3B, 3 Flute
Category
Spiral-Point STI Taps
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

OSG
Manufacturer Part Number
12502100
Type
H3 / 2B-3B, Plug Chamfer
Flute
3
UNC
7/8"-9

Technical Documents

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OSG Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The OSG Screw Thread Insert STI Tap is a spiral-point tap designed for threading holes to accept screw thread inserts. This 7/8"-9 UNC tap features an H3 / 2B-3B tolerance, 3 flutes, and a plug chamfer (MPN 12502100).

Frequently Asked Questions

What is an OSG Screw Thread Insert STI Tap used for?

An OSG Screw Thread Insert STI Tap is used to cut internal threads in a pre-drilled hole before installing a helical wire thread insert. It is commonly applied in automotive, aerospace, and general manufacturing to repair or reinforce threads in aluminum, cast iron, and steel components.

What are the specifications of the OSG STI Tap 12502100?

The OSG STI Tap 12502100 has a thread size of 7/8"-9 UNC, a spiral-point design, 3 flutes, and a plug chamfer. It is ground to H3 tolerance for producing 2B-3B class threads. This tap is designed for through-hole threading and is made from high-speed steel for durability.

Where to buy OSG STI Taps worldwide?

You can source OSG STI Taps worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on the OSG 12502100 or other OSG threading tools.

How to select the correct OSG STI Tap for a thread repair?

To select the correct OSG STI Tap, match the tap thread size and pitch to the thread insert you plan to use. For a 7/8"-9 UNC insert, choose the OSG 12502100 with H3 tolerance for 2B-3B class threads. Ensure the tap chamfer type (plug) suits your hole depth and material.

Used in

Common applications for OSG
Automotive engine block production — OSG micro drill bits for oil gallery and coolant passage drilling in cast iron
Medical device manufacturing — OSG micro drill bits for drilling bone screw pilot holes in stainless steel implants
Aerospace component machining — OSG micro drill bits for fastener holes in titanium alloy structural parts
Mold and die making — OSG micro drill bits for cooling channel drilling in hardened tool steel (HRC 45-50)
Electronics enclosure fabrication — OSG micro drill bits for precision holes in aluminum alloy housings (with appropriate coating selection)
General engineering job shops — OSG micro drill bits for small-diameter hole drilling in mild steel and alloy steel parts

OSG Products

3G Electric supplies OSG spiral-point sti taps. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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