The type of surveying tripod you need to buy will depend on the instrument it will support and the work conditions or environment. With this blog, we have put together helpful information to assist in deciding what the best options are to meet your needs.
1. The material
a) Wood: Is the most traditional material for tripods and is also the most stable, as wood is not highly affected by temperature changes. Make sure to get a wooden tripod with a good protective coating. Plastic coating is preferred, but both plastic and paint coatings will work well. Wooden tripods are most ideal for extended setups, and will have the least variance over the course of the set up.
b) Aluminum: Aluminum Tripods are usually inexpensive and lightweight, making it ideal for light use when set-ups are often changed. Aluminum is not affected by humidity. Being a metal, aluminum can slightly expand and contract due to temperature changes. Aluminum tripods provide the most ideal for setups that only last a short period of time, say an hour or less. Aluminum tripods are more economical, light-weight, and also long-lasting. They are ideal for leveling applications.
c) Fiberglass: Fiberglass is one of the most popular choices of surveying tripods. Fiberglass tripods are fiber reinforced material that has minimal variance due to temperature changes. Fiberglass is resistant to the elements and provides a very strong and long-lasting surveying tripod.
2. The Tripod Head
The tripod head is just that, it's the top of the tripod and is a surface for the surveying instrument to rest on and mount to. There is two head options available, dome or flat. This is mainly just a difference of preference. Both heads will do the same functions and work well with most surveying instruments. Circular dome are ideal for compensated instruments and lasers. A flat head surveying tripod is without a question the most popular tripod on the market today.
3. The Clamps
On a surveying tripod, the clamps hold the legs in place when they are extended.
a) Quick Clamp Tripods - can be set quickly. Simply extend the legs to the desired height and flip the lever. This will lock the legs in place. Some surveyors prefer not to use the quick clamps because if something accidentally catches the lever it could unintentionally unlock the clamp. Quick clamps do feature a bolt to adjust how tight the clamp will lock. Quick clamp tripods are great if your work requires frequent and multiple set ups.
b) Screw Clamp Tripods - To use a screw clamp set the tripod to the desired height and hand-tighten the screws to the desired tension. The screw can be located on the center or on the side of the clamp. Screw clamps take a little longer to set up but cannot be accidentally unlocked easily, which helps protect heavier surveying instruments from a collapsing tripod. We also recommend screw clamp tripods when the user plans to use heavier instruments like robotics, total stations, or GPS equipment since the screw clamps get tighter and there is less chance of a clamp slipping loose and causing a tripod to fall over damaging the instrument.
c) Combination Clamp Tripods - Some tripods have both a quick and a screw clamp that can be used together at the same time or separately.
4. Heavy or Lightweight
Another important factor to consider is the weight of your instrument. Each tripod will list a recommended maximum weight. Even if tripod will support the weight of the item if the surveying instrument is too heavy for the tripod it could cause it to warp over the time of the set up and cause the measurements to be inaccurate.
5. Tripod Stabilization
When working on slick surfaces like finished concrete or indoors, you'll want to buy a tripod stabilizer. Tripod stabilizers come in several styles. One style of tripod comes with a strap that is routed through a loop or bracket on each leg which is tightened and this keeps the three tripod legs from spreading apart. Another style of tripod stabilizer is one the user places on the ground or floor and its a triangle that has three holes in each vertex, where the tripod feet tips rest in, which keeps the tripod legs from spreading.
6. The Tripod Feet
The feet probably suffer the most wear and tear of all the tripod components. Some tripods offer replaceable feet. This way if anything does happen to the feet you can just replace them with out having to replace the whole tripod. There are also optional feet covers available for indoor use. When steel tips become more of a hazard than a help. The covers provide a good slip resistant base for the tripod. And, as most land surveyors know, the feet need to be strong for pushing into the ground to get a stable set-up.