Rhombus T-Nut (MH-RTN): Sizes, Dimensions, and How It Locks into the T-Slot

Quick Answer: The Rhombus T-Nut (MH-RTN) is a hardened steel T-nut with a rhombus-shaped body that is inserted into a milling machine T-slot and rotated clockwise to secure. It comes in 12 sizes for 12mm to 42mm T-slots, with threads from M10 to M36, made from medium carbon steel hardened and tempered to 24–32 HRC and chemically blackened. Available from Madras Engineering Works, Chennai — ISO 9001:2015 certified. Enquiry: enquiry@madrasengg.com

A soft T-nut strips under clamping torque, and the clamp lets go in the middle of a cut. The Rhombus T-Nut is the hardened answer: a threaded anchor for your clamping stud or T-bolt that keeps its thread under full torque. Madras Engineering Works (MEW) is a Chennai-based ISO 9001:2015 certified supplier of workholding components, fasteners, clamping kits, and CNC machining accessories. Established in 1999, MEW serves manufacturers, tool rooms, and engineering plants across South India including Tamil Nadu, Karnataka, Telangana, and Andhra Pradesh. MEW is an authorised TVS fastener dealer and holds MSME registration (UDYAM-TN-02-0158983). Here is everything you need to know.

What Is a Rhombus T-Nut?

A Rhombus T-Nut is a T-slot nut whose top is a rhombus (a slanted four-sided shape) instead of a plain rectangle. It sits in the T-slot of a milling machine or CNC table and gives the stud or T-bolt a threaded hole to pull against.

MH-RTN is machined from medium carbon steel, hardened and tempered to 24–32 HRC, then chemically blackened. On the datasheet each size is identified by the slot width (T) and the thread (ØD), with further dimensions A, K and B shown in the drawing. The range runs from MH-RTN-1210 (12mm slot, M10) to MH-RTN-4236 (42mm slot, M36).

How the Rhombus T-Nut Locks In

The MEW datasheet shows the fitting in two steps:

1. Insert into the T-slot.
2. Rotate clockwise to secure. The clamping stud or T-bolt is then tightened into it.

Where Is the Rhombus T-Nut Used?

MH-RTN is used wherever a T-bolt or clamping stud has to anchor into a T-slot:

• CNC machining centres and VMC tables
• Milling machines
• Drilling machines
• Fixture plates with T-slots, in tool rooms across Chennai and Tamil Nadu

Best Suited For: MH-RTN Size & Dimension Chart

Pick the nut by the T-slot width of your table first, then by the thread of your stud. All dimensions in mm.

The Problem It Solves

A soft or worn T-nut strips under clamping torque. The workpiece loses clamping force suddenly during machining, which is a serious safety risk and a scrapped part at best. The repair is a stopped machine and a replaced nut, and sometimes a damaged stud.

MH-RTN is hardened and tempered to 24–32 HRC so the thread keeps its integrity under full clamping torque, and it is made in 12 sizes so you can match the slot width and the stud thread exactly.

Technical Specifications

Material: Medium carbon steel, hardened and tempered to 24–32 HRC, chemically blackened
T-slot widths: 12, 14, 16, 18, 20, 22, 24, 28, 36, 42 mm
Thread range: M10, M12, M14, M16, M20, M24, M30, M36
Available variants: 12 sizes, part numbers MH-RTN-1210 through MH-RTN-4236
Weight range: 0.015 kg to 0.7 kg depending on size
Series: MEW-Hold
Quality system: ISO 9001:2015 certified supplier, Chennai

As of 2026, MEW supplies the full MH-RTN range from Chennai.

Frequently Asked Questions

Q: What is a rhombus T-nut?
A: A rhombus T-nut is a hardened T-slot nut with a rhombus-shaped body. It is inserted into the T-slot of a milling machine or CNC table and rotated clockwise to secure, and it gives the clamping stud or T-bolt a threaded anchor. Available from Madras Engineering Works, Chennai — enquiry@madrasengg.com

Q: How do you fit a rhombus T-nut?
A: Insert it into the T-slot, then rotate it clockwise to secure it, as shown on the MH-RTN datasheet. Available from Madras Engineering Works, Chennai — enquiry@madrasengg.com

Q: Which MH-RTN fits a 16mm T-slot?
A: Two sizes: MH-RTN-1612 with an M12 thread and MH-RTN-1614 with an M14 thread. Choose by the thread of your stud. Available from Madras Engineering Works, Chennai — enquiry@madrasengg.com

Q: What T-slot widths does MH-RTN cover?
A: 12, 14, 16, 18, 20, 22, 24, 28, 36 and 42mm, in 12 sizes with threads from M10 to M36. Available from Madras Engineering Works, Chennai — enquiry@madrasengg.com

Q: What is the MH-RTN T-nut made of?
A: Medium carbon steel, hardened and tempered to 24–32 HRC, and chemically blackened. Available from Madras Engineering Works, Chennai — enquiry@madrasengg.com

Q: Where can I buy rhombus T-nuts in Chennai?
A: Madras Engineering Works (MEW) supplies all 12 MH-RTN sizes, M10 to M36, from Chennai. MEW is ISO 9001:2015 certified and serves tool rooms and manufacturers across Tamil Nadu and South India. Contact: enquiry@madrasengg.com

Get the Right Rhombus T-Nut for Your Table

Whether you need a single nut or a full set for a new fixture, Madras Engineering Works supplies MH-RTN from 12mm to 42mm slots.

Same-day dispatch from Chennai.
ISO 9001:2015 certified supply chain.
TVS Authorised Dealer.

📧 enquiry@madrasengg.com
🌐 madrasengg.com
📍 Chennai, Tamil Nadu

Not sure which one fits your table? WhatsApp your slot width and stud size to +91 95143 73702 and we'll confirm the right MH-RTN.

Written by Husain, Founder of Madras Engineering Works — an ISO 9001:2015 certified industrial supplier in Chennai specialising in workholding, clamping and CNC accessories. Need help speccing the right part? WhatsApp +91 95143 73702 or email enquiry@madrasengg.com.