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What size tap do you use for a 1/4 28 HeliCoil?

What size tap do you use for a 1/4 28 HeliCoil?

Tap Size: 1/4-28 STI. Drill Size: 17/64″

Are HeliCoil taps standard sizes?

Two master sets for inch sizes are available – Inch Coarse and Inch Fine. The coarse set contains five sizes: 1/4, 5/16, 3/8, 7/16, 1/2 and 5/8. The fine set has size sizes: #10, 1/4, 5/16, 3/8, 7/16 and 1/2. Each set has a drill, tap, installation tool, a quantity of inserts for each size and complete instructions.

What size tap do you use for a 1/4-20 Heli-Coil?

Material: 18-8 (304) Stainless Steel. Type: Free Running. Tap Size: 1/4-20 STI. Drill Size: 17/64″

What size drill bit do you use for 1/4-20 Heli-Coil?


Insert Size Drill Size Wire Thread Insert Length
12-24 5.8 mm 0.216
1/4-20 6.7 mm 0.250
5/16-18 8.3 mm 0.312

What size tap is used for a 1/4 20 helicoil?

What is helicoil tap drill?

Heli-Coil tanged inserts are larger in diameter before installation than the tapped hole. During installation, the inserting tool applies torque to the tang reducing the diameter of the leading coil permitting it to enter the tapped thread. Tangless inserts eliminate the need for tang break-off and retrieval.

What size is the tap for 1/4-20 HeliCoil?

What size HeliCoil do I need for 1/4-20?

What size tap do you use for a 1/4 20 HeliCoil?

Can you use a standard tap for a HeliCoil?

The standard STI tap can be used as a basic tool to create threads ideal for threaded inserts. When preparing a hole to accept a Heli-Coil wire screw thread insert, a Screw Thread Insert or STI tap is used to prepare the hole. The recommended drill is utilized to open the hole to the correct minor diameter.

How to size helicoil?

Nominal length is a calculated number and cannot be measured in the free state.

  • For Tangless CoilThread inserts,the number of free coils is the total number of convolutions (counted from notch to notch) and has a tolerance of ±1/4 coil.
  • Tangless inserts are available for select UNC&UNF sizes up to 3/8″,and select metric coarse sizes up to M12.
  • What size tap for Heli Coil?

    Standard Plug (4-Thread Chamfer): Easy starting for through-holes and blind holes

  • Standard Bottoming (2-Thread Chamfer): Ideal for blind holes drilled to a minimum depth
  • Spiral Pointed Plug (4-Thread Chamfer): Free-cutting for use in long through-holes and in blind holes with chip clearance
  • What size drill do you use for tap?

    The best overall size drill bit for the 5/16″-18 tap is 17/64″ drill bit, which corresponds to an F drill bit. Figuring out what size drill bit you need for a 5/16″ tap starts with understanding a bit about sizing differences. When we talk about the 5/16″ tap, keep in mind that there are two measurement variations; an 18 tap and a 24 tap.

    How to install a helicoil?

    Align the insert

  • Thread the insert onto the installation tool
  • Feed the tool with the insert on it into the STI tapped hole
  • Ensure that the helicoil is somewhere between ¼ to ½ turn below the surface.
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