Mechanical Indicators: Features & Tips
Chicago Dial Indicators...
Unmatched Precision in Measurement
Chicago Dial Indicator Co. offers a full line of dial indicators and accessories to expand their usefulness. The advanced, simplified design of these gages is based on over 60 years of experience in manufacturing dial indicators which are well known for their accuracy, sensitivity, trouble-free long life, and ease of operation.
Click to view Mechanical Dial Indicator Design Features and Diagram
- Heat-treated stainless steel racks, gears and pivots
- Non-magnetic hairsprings
- One piece forged brass case
- Fluted bezels for easy, no-slip grip
- Acrylic plastic crystals are non-yellowing, provide high scratch resistance
- Fine, easy-to-read graduations on non-glare dials (English: white, Metric:
- Four-position back permits 90 degree dial positioning
- Chrome plate finish
- All CDI indicators are supplied with serial # labels
Balanced and Continuous Dial Models
Two types of dials are offered in all models: Balanced dials with plus and minus readings for comparative work and continuous dials for direct measurement of length and depth. Long-range continuous dial indicators have single or dual revolution counter hands to facilitate reading. CDI can furnish special dials to fit your specifications. Price on application.
Graduation and Range
CDI dial indicators are built to provide precise measurement with graduations of .0001", .00025", .0005", .001" and .010" (0.002mm, 0.005mm to 0.01mm). Total range of travel is .020" to 5" or 0.5mm to 50mm.
All CDI dial indicators are available with fully jeweled movements. Sapphire bearings mount directly into upper and lower plates with no auxilliary bushings, reducing the possibility of misalignment. Highly polished jewels have an olive hole design which, together with CDI hardened and burnished pivots, provide lowest possible bearing friction and maximum resistance to wear. Jeweled bearing movements are recommended for heavy use applications and whenever extremely high sensitivity is required.
CDI's market niche has always been OEM or special application dial indicators. If you have a special application contact our sales department for assistance. We have been manufacturing specials for over 60 years and there is a good chance we have already seen your application or experienced something similar.
CDI offers fast repair service and return of indicators damaged by accident or worn through long periods of constant use. Each gage is disassembled and cleaned: worn or broken parts are replaced and the gage is reassembled and calibrated.
Please use this Diagram for help in descibing your problem over the phone.
CDI ONLY REPAIRS CDI MANUFACTURED DIAL INDICATORS.
Here are some useful tips to help you select the Chicago Dial Indicator that will best meet your requirements:
Select an indicator that is closest to 10% of the tolerance spread. For example, if acceptable tolerance is .001", select an indicator having .0005" graduations. This will give a span of 10 divisions on the dial.
Two main selection criteria here are:
- How much space is available for positioning the indicator?
- How far away must the indicator be read?
Select a dial having the required graduations. The ideal range is one which allows the tolerance spread to cover one-tenth to one-fourth of the dial.
All AGD indicators have a total range of 2.5 times the range per revolution, sufficient for most applications. Longer total range requirements up to 5" or 50mm can be met with one of CDI's long range dial indicators.