Taking tree diameters is simple with this handy pocket size fibreglass tape. Measures up to 3m diameter. Please note: the pi rule side can be easily mistaken as an inch rule, it is not, but in fact a clever rule calculated to measure the diameter of a cylindrical object. To measure length, use the standard metric side, or to measure diameter, use the pi rule side. For example, to measure the diameter of a pipe, wrap the pi rule around the pipe and where the zero mark aligns with the rule, that is your reading in cm diameter.
A diameter tape (D-tape) is a form of dendrometer that is typically used to measure diameter of a tree at breast height (DBH). DBH is measured at a fixed height of 4.5 feet (140 cm) above the ground in the United States, or 1.3 meters in Canada and many European countries. DBH is measured up high to avoid measuring a tree's butt swell. Butt swell is where the base of the tree is unconventionally thicker than the rest of the tree. Height and diameter are used to determine the volume of a given tree.
- Strong flexible fibreglass tape
- ABS case
Length: 10m Length, 3m Diameter
Body case: ABS Plastic
Warranty: 12 months
Well, many years ago, I started my career working for a company that manufactured large (150mm diameter), high voltage (400kv, 2000 amp) power cables that were buried deep underground, or laid in cable trays in tunnels.
An essential part of our quality control tools was a diameter tape. We used it many times a day. Instead of graduations in mm (or inches), these diameter tape measures are graduated in units of circumference of circular (i.e., round) objects. Place the tape around the object to be measured, and what you read on the tape is the diameter of that object.
I've been tying to find one of these for a number of years. I do some DOC work and more often than you you might expect come across an old rusted galvanised pipe (or even some of the newer black ABS pipe that someone's damaged). We look at it trying to guess whether it's a 40mm or 50mm diameter pipe. Some of my colleagues try to use regular tapes to measure the diameter, - good luck on that one. I hand them my diameter tape, they wrap around the pipe, et voila, they read the diameter directly off the tape. I've also used it for vent and duct pipes - I don't know about you, but I find it tough to measure a 25mm or 30mm duct pipe from the outside.