Linear Digital Measuring Device

Simple Slide Length Measuring Machine
Simple Slide with built in encoder strip
Custom V-Groove for product measuring stability
Linear Digital Reader attached to carriage for mobility
Simple Slide Linear Digital Measuring Device
Fully Customized Linear Digital Measuring Device

Product Overview
  • 112" Measurable Travel Length
  • Overall Lengths up to 120"
  • Available in Carbon Steel or Stainless Steel Shafts and Bearings
  • Optical Linear Encoder: 1um Accuracy
  • Digital Readout Resolution: .001"
  • Suitable for Round, Flat, or Square Measurement Features
  • Consistent Repeatable Physical Stop
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The following article describes our first LDMD Generation 1. This unit is now followed and improved upon by SMI's LDMD2. This original article describes the basic concept used to create this unique measuring device. The prototype LDMD 1 is still in use on our shop floor today and is used daily for accurately measuring cut to length shafting products.

To go to the New LDMD 2 information, follow this link: LDMD 2

Specialty Motions, Inc.'s NEW Linear Digital Measuring Device (LDMD) is an ideal tool for measuring the length of long round, flat or square material. This length measuring device was created based on a common need from our customers, as well as our own, to measure long length materials. Lengths much longer than the typical vernier caliper could measure at a reasonable cost.

The LDMD is a simple electronic linear measuring tool is based upon a simple need: measure various lengths up to 112" with a high degree of accuracy and consistency. The LDMD is capable of measuring lengths up to 112" with a tolerance band of .002" (currently). Longer lengths and greater accuracies will be available soon.

The LDMD's single axis digital readout display accepts 5v quadrate encoder feedback and is useful for a variety of applications. The digital readout is constructed of 1.5mm sheet metal with a height of 2.8", width of 5.8" and a depth of 2.75" and weighs 1.07lbs. The DRO is typically attached directly to the rolling carriage for ease of operation, ergonomics and simple wire management.

Originally we used one of our Simple Slides as the basis of our design and incorporated a linear scale on the base and a Read Head integral to the carriage. The material to be measured is laid flat in the LDMD’s base and butted against an end stop. The carriage is then moved into position to touch off on the end of the shaft (or whatever is being measured) and the length reading is read directly from a Digital Read Out (DRO). The DRO display can be mounted to the carriage itself or fixed in a different location for convenience and protection.

The SA100 single axis digital readout displays accept 5v quadrate encoder feedback and are useful for a variety of applications. The digital readout is constructed of 1.5mm sheet metal with a height of 2.8", width of 5.8", depth of 2.75" and weighs 1.07lbs (bracket included). Optional 6' extended wiring is available for either desk, or wall mounting.

The LDMD can be mounted as a fixed unit using the base mounting holes or it can be attached to SMI's Mobile table structure (MDT) with locking wheels creating a transportable measuring device. The center of the LDMD has been modified with a "VEE" groove to allow the material being measured to accurately nest for measurement. We used a "VEE" to accommodate round shaft material but any specific design can be incorporated for your needs.

The LDMD is a precision device so care must be taken in placing materials in the nesting area and cleanliness can be an issue. However, this is a first generation product and as we evolve, we will be building for a more complex environment. However, initially we are focused on simple, cost effective and accurate designs.

Send us your needs and let SMI build an LDMD to fit your needs. An example of price for budgetary calculation in its basic configuration is $4500 for 90" of length measurement and ready to use out of the box. Plug into any 110 VAC outlet and your unit is ready to measure.

The LDMD is used in our shop daily since we specialize in Hardened and Ground Linear Shafting from Thomson. As one of Thomson’s largest cut centers, we work in various cut lengths all day long and most of our lengths would not fit the typical measuring device without paying extraordinary prices for the accuracy we needed. We built and use our own LDMD every day and have not been disappointed or (worse yet), rejected for length errors.

Available Options

Moveable Device Stand (MDS)

Linear Digital Measuring Device Stand

Our LDMD Mobile Stand is constructed of an extruded t-slot aluminum alloy for easy and fast assembly with locking wheels.
Varies sizes available.


Installation Kit

Linear Digital Measuring Device Stand

Cable extension for desktop or wall mounting.
Available in 6Ft.

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Specialty Motions, Inc.
1801 Railroad Street, Corona, CA 92880
Tel: (951) 735-8722 | (800) 283-3411
Fax: (951) 735-8915

Monday - Friday 7:30AM to 4:30PM PST

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