Get a Grip: Why Expanding Mandrels from 1st MTA Are the Smart Choice for Internal Workholding

When it comes to workholding, external clamping gets most of the attention — but internal gripping is often the real challenge. Whether you’re working with thin-walled parts, precision bores, or long, awkward components, choosing the right mandrel can make or break your machining accuracy. That’s where expanding mandrels from 1st MTA come in.

We don’t just supply workholding — we engineer it. From standard solutions to fully custom designs, our expanding mandrels are built to deliver accuracy, repeatability, and reliability where it matters most.

What Is an Expanding Mandrel? 

Expanding mandrels are internal clamping devices used to hold components securely from the inside. As the sleeve expands, it grips the bore of the part with uniform pressure — making it ideal for applications where external clamping isn’t possible or could cause distortion.

At 1st MTA, our expanding mandrels are suitable for:

• Turning
• Milling
• Grinding
• Vertical Boring 

They offer a safe, precise, and efficient method of internal workholding — especially for delicate or high-value parts.

Why Choose 1st MTA?

Buying a mandrel isn’t just about dimensions — it’s about performance. That’s why engineers and manufacturers across the UK choose 1st MTA as their trusted partner.

Here’s what sets our mandrels apart:

Precision You Can Rely On

• Standard expansion range of 0.8mm (0.032”)
• Accuracy up to 0.013mm (0.0005”) T.I.R., or even closer if required
• Positive pull-back location for reliable repeatability

Superior Clamping Performance

• Even pressure distribution across the sleeve — no pressure marks on bores
• Secure hold that eliminates wobble and chatter, even on longer parts
• Quick and easy loading/unloading to reduce setup time

Versatility Built In                                                  

• One mandrel can be used with a range of sleeves
• Multiple sleeve options available for different diameters or component lengths
• Suitable for both short production runs and high-volume machining

Custom Solutions? Absolutely.

Let’s face it — not every component plays by the rules. When your part has a non-standard bore, tricky length-to-diameter ratio, or simply doesn’t work with off-the-shelf options, our custom expanding mandrels are the answer.

Whether you need:

• A unique expansion range
• Oversized or miniature mandrel bodies
• Long-reach sleeves to eliminate vibration
• Special materials for specific environments

Our technical team will work with you to design a mandrel that fits your exact requirements — no compromises, no shortcuts.

Why Trust 1st MTA?

At 1st MTA, we’ve been helping engineers solve workholding challenges for decades. We don’t believe in one-size-fits-all — we believe in listening, understanding your process, and delivering the right solution, first time.

When you work with us, you get:

• Expert technical advice from real engineers
• Access to both standard and fully bespoke solutions
• Proven performance across a wide range of industries
• A partner who’s as committed to precision as you are

We don’t just help you get a grip — we help you keep it.

Get in Touch

Have a part that’s proving tricky to clamp internally? Whether you’re working with precision components or production volumes,

1st MTA has the experience, products, and technical knowledge to help.

📞 Call our team
📧 Send us your drawings
🛠️ Let’s engineer the right solution — together