Why write a review on a steel tape? Reading a tape is much more difficult than you are lead to believe. There are so many factors when Surveyors/Engineers take measurements that I felt it would be important to discuss those.

Advantages and Disadvantages

This brand of tape is the only tape our company uses, Previously at my last company we used only nylon tapes (Same Brand).

The biggest difference between nylon and steel tapes is that nylon tapes will not rust, however they are much more flexible, which allows them to stretch thus providing an inaccurate measurement. Although the tape will not kink and is almost indestructible, it still can rip, tear, and be cut.


However, steel can Kink if heavy weight is applied to it or it is improperly pulled. (like when cars run it over while using it on Road Construction) The part of the tape that breaks making it un-repairable is the end piece which is the "Zero" end or the beginning of the tape. The piece it self is metal and strong, but it usually gets torn off or crushed by something making it useless.

Remember:

Tape manufacturers do not guarantee 200 ft steel tapes to be exactly 200.00 ft.
An error due to the incorrect length occurs every time the tape is used.
This error can be accounted for by correcting the value of measured lengths.

TENSION ERRORS

If tension is greater than standard the tape will stretch.
If less than standard tension is applied the tape will be shorter than standard.
Modulus of Elasticity for steel
29,000,000 lb/in2
2,000,000 kg/cm2
This error can be accounted for by correcting the value of measured lengths.

TEMPERATURE CORRECTIONS

Steel tapes are standardized at 68° F (20° C). Meaning at this Temperature the tape will read “true” to manufacture standards.
A temperature higher or lower will change the length of the tape.
Coefficient of thermal expansion for steel
0.0000065 per unit length per ° F
0.0000116 per unit length per ° C
Temperature of the tape can be quite different from the air temperature measured.
This error can be accounted for by correcting the value of measured lengths.

POOR ALIGNMENT BOTH HORIZONTIAL & VERTICAL

This error occurs when one end of the tape is off-line or there is an obstruction in-line.
The actual distance will be less than the measured distance.
These errors may be reduced by carefully following correct field procedures.
This error can be accounted for by correcting the value of measured lengths.

This error occurs when the tape is inclined in a vertical plane.
The actual distance will be less than the measured distance.
These errors may be reduced by using a hand level or by differential leveling to account for differences in elevation.
This error can be accounted for by correcting the value of measured lengths.

SAG ISSUES

A steel tape not supported along its entire length will sag.
The tape length stays the same, so the sag reduces the horizontal distance between the end graduations of the tape.
Sag may be reduced by increasing the tension, but not eliminated.
This error can be accounted for by correcting the value of measured lengths.

IMPROPER PLUMBING OF TAPE

This error is random in that it may make the measured distance too long or too short.
Touching the plumb bob on the ground or steadying it can decrease the swinging motion.
This error cannot be accounted for by correcting the value of measured lengths.

FAULTY MARKING

Result of incorrect placement of chaining pins or holding of tape
Debris, vegetation, and stones may deflect the chaining pin and increase this error.
Careful placement of chaining pins and then checking the measurement will reduce errors.
This error cannot be accounted for by correcting the value of measured lengths.

INCORRECT READING OR INTERPOLATION (HUMAN ERRORS)

The hardest error to correct because this error is random as the result of incorrect interpolation while reading the tape.
This error cannot be accounted for by correcting the value of measured lengths.

I hope this was informative and help you realize some of the mistakes you might make while measuring.

For Houseline Surveying & Smaller Jobs we use the Keson 100ft Steel Tape

See Also: Keson 300' Fiberglass Tape , Craftsman 100’ Steel Tape



Recommended: Yes