Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

This is an AMP page - Open full page! for all features.

• the most efficient way to navigate the Engineering ToolBox!

# Improvised Torque Wrench

If you don't have a torque wrench available - or if you want to check the readings of the one you have - it is easy to improvise by using a standard wrench and a scale as indicated in the figure above.

The moment - or torque - can be calculated

T = F a                                       (1)

where

T = moment or torque (Nm, lbf ft)

F = applied force (N, lbf)

a = length of the wrench (m, ft)

Note! - Most scales in the SI unit system measures weight - force due to the acceleration of gravity - in kg.

The reading from the scale can be converted to N by using

F = m g

where

m = reading of the scale (kg, lbf)

g = acceleration of gravity (9.81 m/s2, 32.17 ft/s2)

### Example - Measuring Torque with a standard Wrench and a Luggage Scale - readings in kg

The reading of the scale at the end of the wrench is 10 kg. The length of the wrench is 0.3 m. The moment exerted can be calculated

T = (10 kg) (9.81 m/s2) (0.3 m)

= 29.4 Nm

### Example - Measuring Torque with a standard Wrench and a Luggage Scale - readings in lbf

The reading of the scale at the end of the wrench is 20 lbf. The length of the wrench is 6 in. The moment exerted can be calculated

T = (20 lbf) (6 in)

= 120 in lbf

= 10 lbf ft

### "Luggage Weight - Wrench" Online Torque Calculator

Wrench Length (m, in)

SI

Imperial

### Scale Wrench Torque Diagram - SI units

#### Example - Torque Settings for a Cylinder Head

The torque settings for a cylinder head in a car engine are specified to 30 Nm.

According to the diagram above with a wrench with length 0.2 m - the scale readings should be approximately

14 kg

## Related Topics

### • Mechanics

Forces, acceleration, displacement, vectors, motion, momentum, energy of objects and more.

## Related Documents

### Angular Motion - Power and Torque

Angular velocity and acceleration vs. power and torque.

### Bolt Torque Calculator

Calculate required bolt torque.

### Car - Required Power and Torque

Power, torque, efficiency and wheel force acting on a car.

### Disk Brakes - Torque and Force

Forces and torque activated with disk brakes.

### Electric Motors - IEC and NEMA Standard Torques

IEC and NEMA torque classifications of electrical motors.

### Electric Motors - Torque vs. Power and Speed

Electric motor output power and torque vs. rotation speed.

### Gear Reducing Formulas

Output torque, speed and horsepower with gears.

### Levers

Use levers to magnify forces.

### Lifting Wheels

Loads and effort force with lifting wheels.

### Metric Bolts - Tightening Torques

Recommended thightening torque metric bolts.

### Piston Engines - Displacement

Calculate piston engine displacement.

### Reduced Torque with Lubricated Bolts

Lubrication effect on bolt tension and torque.

### Screw Jack - Effort Force vs. Load

Screw jacks and effort forces.

### Torque - Work done and Power Transmitted

The work done and power transmitted by a constant torque.

### Torque or Moment of Force - Online Converter

Torque or moment - the tendency of a force to rotate an object.

### Torsion of Shafts

The torsion of solid or hollow shafts - Polar Moment of Inertia of Area.

### US Bolts - Tightening Torques

Recommended bolt torques.

### Whitworth Bolt Torques

Torque specifications Whitworth bolts.

## Search Engineering ToolBox

• the most efficient way to navigate the Engineering ToolBox!

## SketchUp Extension - Online 3D modeling!

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp from the Sketchup Extension Warehouse!