Return to slide rule makers

M H Mear and Company LTD
Calculator Designers
Ramsden Mills, Britannia Road, Milnsbridge, Huddersfield, W. Yorkshire, England HD3 4QG

Telephone: 01484 648181   Fax: 01484 657098

Note: The summary below is based on the company's calculator catalogue. For full details and price list contact the company at the address above or visit their web site at: 

EACH CALCULATOR solves a particular frequently met problem in a simple yet accurate manner.
ANY COMPLEXITIES of the basic formula or method are built in and handled automatically by the instrument so that only a simple
setting of dials to length, width, diameter, temperature, etc., is necessary.

We specialize in the design of high quality technical calculators for solving sometimes simple, but usually complex, frequently recurring problems common to many industries.

Our current range is shown in this booklet and all of them will be found to be tremendous time savers, up to date in design and technical detail, and capable of recovering their small cost in the time saving alone on the first few calculations.

Of the highest quality, precision made from non-warping white and clear acrylic, with main dials 3 mm thick and subsidiary dials 1.5 mm thick. All scales and lettering are clearly and sharply engraved, not printed, and are filled in multicolours to facilitate use.

Standard instruments are calibrated in Imperial units, but most of them are now available in exactly similar designs calibrated in S.I. Metric units and some calibrated in U.S. gallons. The availability of Imperial, Metric or U.S. models is indicated for each calculator.

Our standard instruments can be supplied engraved with clients’ name and advertising copy in quantities of 100 or more at appreciable discounts, or for 50 or more we can gold block these details on the plastic cases. Special calculators can be made to customers’ individual requirements.

Because the full capabilities and value of our instruments can only be appreciated by actual handling and use, we are glad to supply on 10 days’ free trial to United Kingdom business addresses who have an account with us. To private addresses and business addresses who do not have an account with us, we can
supply against cash with order with a 10 day money back guarantee if not found suitable.

DELIVERY is normally by return of post.

Heating Calculator for Energy Efficient Houses   — This calculator gives the heat requirements of new homes built to meet the improved standards of insulation laid down in the 1990 Building Regulations
Domestic Central Heating Calculator An instrument, simple and quick to use, which determines the heating requirements for older types of domestic premises and also the sizes of all the equipment needed for the installation.
Conservatory Heat Loss Calculator For conservatories or garden rooms, this calculator determines the heat loss through the fabric of the room by setting dials to room dimensions, U values and temperature difference.
Industrial Heating Calculator Heat losses through the structure are handled one one side of the calculator. Pipe sizing is simplified. Radiator size, boiler size and pump size are obtained on the reverse side.
Ducting Calculator A complete calculator for determining duct sizes, velocities and pressure losses for large or small ducting systems.
Warm Air Heating Calculator A complete method for designing warm air heating installations once room heat requirements have been determined (using Domestic Heating Calculator).
Packaged Air Conditioning Calculator Approved by the Air Conditioning Advisory Bureau
This instrument has been specially produced to facilitate the design procedure for packaged systems.
Psychometric Calculator This calculator determines all the properties of moist air from any of three basic sources of measurement.
Probability & Statistical Calculator This instrument solves quickly and accurately the statistics involved in setting up schemes for control of Quality of goods received and Quality in batch and mass sampling.
Pipe flow Calculator (Turbulent) This calculator determines the required pipe size, flow or pressure for any liquid e.g. water, fuel oils, solvents and also for any gas (at low pressure) flowing under turbulent conditions in steel or cast iron pipes.
Streamline flow Calculator This instrument solves the streamline flow formula applicable to the flow of more viscous liquids such as fuel oils, lubricating oils, syrups etc.
Orifice & Nozzle Flow calculator Accurate methods for measuring the flow of fluids in pipe lines by means of various types of orifice plates.
Water Flow Calculator One side of the calculator solves the rational formula for water flow in pipes of circular section.
The reverse side solves the Manning formula for flow in open channels.
Gas Flow Calculator — Cast Iron & Steel Pipes A double-sided instrument for calculations related to the flow of all gases in steel or cast iron pipes.
Gas Flow Calculator — For Plastic Pipes Similar to the above for plastic pipes.
Steam flow Calculator Determines the pressure loss of steam flowing in pipe lines from vacuum up to the critical pressure of 220 bar.
Steelwork Calculator An instrument to determine accurately the weight of any piece of fabricated or rolled steelwork.
Universal Metals Weight Calculator This calculator will give the weight of almost any size or shape of commercial metal including steel and rolled sections.
Combustion Efficiency Calculator The efficiency of a boiler is determined largely by the heat lost to any excess air supplied and the loss in high temperature flue gases.
Electric Lighting Calculator This calculator has been designed to give quickly and accurately the number and size of luminaires for any installation by the lumen method.
Electric Wiring Calculator A single-sided calculator to rapidly determine the voltage drop in cables and to give the required size to meet specified maximum losses.
Helical Spring Calculator This calculator designs helical compression and extension springs.
Timber Calculator For estimating timber quantities and prices.
Brick, Blockwork & Concrete Calculator Designed to give simply and quickly:
   Number of bricks or blocks needed to build any wall.
   Volumes of concrete for various slab thickness
   Area of any surface e.g. paving, glazing, roof, wall
Comprehensive Metric Conversion Calculator — M1.B A pocket-sized instrument with over 300 direct reading conversions.
Feet & Inches to Millimetres Calculator — M2 A handy pocket-sized instrument for converting dimensions.
Conversion Avoirdupois/ Metric — M4 Similar to M2 but for weights.

Return to slide rule makers