MMTB Miniature Break-Over Torque Wrenches

Quick Answer

The MMTB is a miniature preset break-over torque wrench designed for repetitive low-torque fastening. When the preset torque is reached, the wrench breaks over approximately 90°, giving the operator a clear visual indication that the target torque has been achieved.

The MMTB is available in two torque capacities, covering an overall range of 8 to 80 ozf.in (5.6 to 56.4 cN·m). Each wrench is configured with a permanently attached fixed head selected for the application.

Who This Is For

Manufacturing engineers
Process engineers
Quality engineers
Assembly operators
Electronics manufacturers
Medical device manufacturers
Aerospace manufacturers
Instrumentation manufacturers
Precision assembly facilities
Production environments requiring very low torque control

When Should You Use This?

Use the MMTB when:

Very low torque fastening is required
Small or sensitive fasteners are being installed
Repetitive fastening is performed at the same torque setting
A compact wrench is required for restricted spaces
Preventing routine operator torque adjustment is important
A dedicated fixed head configuration is appropriate
A clear visual indication of reaching the preset torque is beneficial

The MMTB's miniature size makes it particularly suited to precision fastening applications where a full-size torque wrench would be difficult to use. The handle measures approximately 3 1/2" long and 3/8" in diameter.

When Should You NOT Use This?

The MMTB may not be the best choice when:

Torque requirements exceed 80 ozf.in
Operators need to frequently change torque settings
Different wrench heads need to be swapped on the same handle
An adjustable wrench with a visible torque scale is required
Electronic torque measurement or fastening data collection is needed
A larger torque wrench is more appropriate for the application

For higher torque ranges, consider the TB or TBIH Break-Over Torque Wrench.

How the MMTB Works

The MMTB uses a preset break-over mechanism to control torque during repetitive fastening.

During operation:

The wrench is preset to the required torque value.
The operator applies torque to the fastener.
When the preset torque is reached, the wrench breaks over.
The approximately 90° break-over movement provides a clear visual indication that torque has been achieved.
The operator stops applying force and proceeds to the next fastening cycle.

Result:

Reduced risk of over-tightening
Reduced risk of under-tightening
Repeatable low-torque fastening
Improved operator consistency
Better process control for sensitive assemblies

Core Features

Miniature preset break-over torque wrench
Designed for very low torque fastening
Two torque capacity options covering 8 to 80 ozf.in
Fixed wrench head permanently attached to the tool
Multiple head types and sizes available during configuration
Approximately 90° break-over movement
Break-over action provides a visual indication when preset torque is reached
Tamper-resistant internal torque adjustment
No external adjustment scale
Lightweight aluminum handle
Compact design for restricted spaces
Designed for repetitive precision fastening
Manufactured to meet or exceed ISO 6789:2017 accuracy and repeatability requirements at ±6% of setting

MMTB Torque Options

The MMTB is available in two torque capacities. Select the option that contains the required preset torque value.

Torque Option	Torque Range	S.I. Range
Option A	8–39 ozf.in	5.6–27.5 cN·m
Option B	40–80 ozf.in	28.2–56.4 cN·m

Together, the two options provide an overall MMTB torque range of 8 to 80 ozf.in.

Model Selection Guide

If you need:	Recommended Configuration
Ultra-low torque precision fastening	Option A: 8–39 ozf.in
Higher low-torque fastening	Option B: 40–80 ozf.in
General fastening with side access	Open End Head
Greater fastener engagement	Box Head
Access around tubing or lines	Flare Nut Head
Internal hex fasteners	Hex Key Head
Repetitive tightening with a bit	Ratchet Head

MMTB Wrench Configuration

The MMTB is a configurable wrench rather than a traditional lineup of individual models.

To configure an MMTB, select:

Torque capacity based on the required torque range
Head type based on the fastener and application
Head size based on the fastener
Preset torque value, if required

The selected wrench head is permanently attached to the MMTB. Unlike the TBIH, the MMTB is not an interchangeable-head torque wrench.

MMTB Fixed Head Options

The MMTB can be configured with five fixed head styles. The appropriate head is selected when the wrench is configured and becomes a permanent part of the tool.

Head Type	Code	Available Size Range	Best For
Open End	OE	7/32"–3/4"	General fastening and side access
Box Head	BH	1/4"–3/4"	Increased fastener engagement
Flare Nut	FN	1/3"–9/16"	Fasteners around tubing or lines
Hex Key	HK	1/16"–5/32"	Internal hex fasteners
Ratchet Head	RH	1/4" Female Hex	Repetitive tightening applications

Open End Head

Open end heads provide side access to the fastener, making them useful where surrounding components prevent access from above.

Box Head

Box heads provide increased engagement around the fastener for improved grip and control.

Flare Nut Head

Flare nut heads provide access to fasteners around tubing, lines, or similar components that prevent the use of a fully enclosed head.

Hex Key Head

Hex key heads are designed for small internal hex fasteners commonly found in precision assembly applications.

Ratchet Head

The ratchet head features a 1/4" female hex interface and supports repetitive tightening applications where repositioning a conventional wrench would be inefficient.

Setup & Torque Adjustment

The MMTB does not have an external torque scale. Its torque setting is established internally and should be verified using a calibrated torque analyzer.

Select the appropriate MMTB torque capacity.
Select the required fixed head type and size.
Determine the required preset torque value.
Verify the wrench using a torque analyzer that covers the required torque range.
Apply torque slowly and smoothly until the wrench breaks over.
Compare the measured torque to the required setting.
Adjust the internal preset as needed.
Repeat the verification process until the required torque value is achieved.
Verify proper operation before placing the wrench into production.

A torque analyzer is required when setting the torque value yourself.

Calibration & Accuracy

The MMTB should be periodically verified and calibrated as part of the facility's torque control program.

The product data sheet specifies that the MMTB is designed and manufactured to meet or exceed ISO 6789:2017 accuracy and repeatability requirements at ±6% of setting.

Common Applications

The MMTB is commonly used in:

Electronics assembly
Medical device manufacturing
Precision instrumentation
Aerospace component assembly
Small mechanical assemblies
Laboratory equipment manufacturing
Miniature fastener applications
Restricted assembly spaces
Production processes requiring very low preset torque

Use Cases (Real-World Examples)

Miniature Fastener Assembly

Problem: Very small fasteners can easily be damaged or stripped when too much torque is applied.

Solution: The MMTB provides a controlled preset torque and break-over indication to help reduce over-tightening during precision assembly.

Restricted Assembly Spaces

Problem: Tight work areas do not provide enough room for a conventional torque wrench.

Solution: The MMTB's lightweight aluminum handle measures approximately 3 1/2" long and 3/8" in diameter, making it suitable for confined fastening locations.

Sensitive Component Assembly

Problem: Delicate components require consistent low torque to prevent fastener or component damage.

Solution: The MMTB provides repeatable preset torque across repetitive fastening cycles while giving the operator a clear visual indication when the target torque is reached.

Dedicated Production Station

Problem: A production workstation repeatedly uses the same small fastener and torque value.

Solution: The MMTB can be configured with the required torque capacity, permanently attached head, head size, and preset torque value to create a dedicated tool for the process.

MMTB vs. TB vs. TBIH

Feature	MMTB	TB	TBIH
Torque Type	Preset	Preset	Preset
Break-Over Mechanism	Yes	Yes	Yes
Head Style	Fixed	Fixed	Interchangeable
Torque Range	8–80 ozf.in	Higher than MMTB	Higher than MMTB
Miniature Design	Yes	No	No
Head Can Be Changed	No	No	Yes
Best For	Very low torque precision assembly	Dedicated production fastening	Production fastening requiring head flexibility

Choose the MMTB when very low torque and a compact tool are required.

Choose the TB when a higher torque range and dedicated fixed head configuration are required.

Choose the TBIH when the application requires interchangeable wrench heads.

Maintenance

Keep the wrench clean and free of debris.
Inspect the aluminum handle, break-over mechanism, pivot point, and fixed head for wear or damage.
Periodically verify torque output using a calibrated torque analyzer.
Recalibrate the wrench according to your facility's calibration schedule and quality requirements.
Verify torque whenever the preset setting is adjusted.
Apply torque slowly and consistently during verification.
Remove damaged or improperly functioning tools from service until inspected or repaired.

Integration & Advanced Notes

Mechanical preset torque wrench requiring no electrical power
Two torque capacities covering 8 to 80 ozf.in
Miniature design for very low torque applications
Fixed head permanently attached to the wrench
Five available head styles
Multiple head sizes available depending on head type
Internal adjustment helps prevent routine operator torque changes
Break-over mechanism provides a clear visual torque indication
Approximately 90° break-over movement
Designed for repetitive production fastening
Configurable by torque capacity, head type, head size, and preset torque value

Media & Supporting Content

Need Help?

Contact Applications Engineering for setup guidance
Speak with Sales for product selection
Call us:
- North America:(408) 850-9978
- International: +44 1428 741756

MMTB Miniature Break-Over Torque Wrenches – FAQ & User Guide