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Prism Pole Best Locking Mechanism
Posted by amdomag on May 5, 2022 at 1:26 pmAs a Leica prism user, my prism poles are all of TLV type. Half of them are Leica poles and the remaining are all Seco. My experience with the TLV system is that the outer rubber disintegrates over time. I doin’t know if replacement is commercially available.
Seco also produces Quick Release, QLV, and Compression Locking system. It appears to me (based on Seco promotional Youtube videos) that the Compression Locking type would last much longer than the rest.
Any idea? Your experience in the field using different types of poles would matter a lot in choosing my next prism poles. Thank you.
jph replied 1 year, 10 months ago 20 Members · 37 Replies- 37 Replies
In order of preference, from least to most …..
The compression sleeve type is the worst, IMO. It is the only type that I just won’t have. Get a single speck of grit in the threads and your goose is cooked. I’ve never had one that didn’t get jammed up and inoperative very quickly when used in the field. But in the showroom or the annual conference display booth they are slicker than slug snot.
The quick release type gets bumped easily and slips. You need to pay constant attention to its position. If you are running only 2d traverses and/or constantly running the pole up and down it can be handy. Nevertheless not my favorite, but has it’s uses.
These lever clamp types (QLV?) are OK but you have to keep them in good adjustment to work well. Can be a bit of a pain (may pinch) to work when your hands are cold.
This type with the twist knob (TLV?) is the best alternative, IMO. Requires the least maintenance. But if you overindulge in your Kung-fu grip exercises with it you can break the rubber knob. Nothing lasts forever, nothing is indestructible.
SECO does sell maintenance and replacement parts for all these. They all get to sucking if not maintained.
Seco make at least one pole that has holes for a locking pin at various heights on the top section
You don’t have to use the fixed heights – you can set any – but with the pin in, it cant slip down.
That’s the best for me
- Posted by: @jimcox
Seco make at least one pole that has holes for a locking pin at various heights on the top section
You don’t have to use the fixed heights – you can set any – but with the pin in, it cant slip down.
That’s the best for me
Locking pins are the way to go. Been burned too often by poor clamp mechanisms.
“…people will come to love their oppression, to adore the technologies that undo their capacities to think.” -Neil Postman - Posted by: @rover83
Locking pins are the way to go. Been burned too often by poor clamp mechanisms.
Caveat. Those pin holes do weaken the rod. I’ve bent a couple by taking a tumble with rod in hand. Not a lot, just enough to make them bind when running up and down. Which means that you can never plumb them well for control or boundary ties again.
I am due for a new rover pole. Anyone have experience with multi-position ‘snap lock’. Do they stay locked at the predetermined positions (ie 2.0M, 1.8M and 1.6M)?
- Posted by: @norman-oklahomaPosted by: @rover83
Locking pins are the way to go. Been burned too often by poor clamp mechanisms.
Caveat. Those pin holes do weaken the rod. I’ve bent a couple by taking a tumble with rod in hand. Not a lot, just enough to make them bind when running up and down. Which means that you can never plumb them well for control or boundary ties again.
May be better to bend the pole (those brass adjusters sure do) than put all the impact into what ever is on the top?
Sounds like you are referring to the Lecia GLS13? If so the pin is great, easier than the Seco pin for sure, but over time/rough use the metal on metal does cause some wear but not an issue of early failure just standard wear and tear. Also the tip of the pole has a wear tip which you need to keep an eye on a wears over time, designed to ensure you get accurate heights.
There’s nothing worse hearing when you’re running the rod on a topo and the instrument person says, “When did you change the rod height to 6.00?”
SECO PN: 5128-22
- 3-Position Carbon Fiber Rover Rod features a one-piece design that is faster and more user friendly
- Ideal for GPS RTK surveys
- The rod telescopes and locks at 3 different heights of 2 m, 1.8 m and 1.6 m and collapses to 1.343 m
- The rod has two locking systems: the no-slip snap-lock and a compression lock that centers the telescoping inner and maintains straightness
- Includes a 40-minute, adjustable circular vial
- Dent-resistant carbon fiber is strong and has a zero coefficient of expansion
- Weighs 1.6 lb (0.73 kg
We use 2m snaplocks for GNSS work and the crews seem to like them, they are pretty tough despite being carbon. Haven’t tried the multi-height style though.
“…people will come to love their oppression, to adore the technologies that undo their capacities to think.” -Neil PostmanCarbon fibre poles are light and nice when new – but I break them
I have had extremely good luck with the genuine Leica poles, years on the GLS11 and I have a newer GLS12 that so far so good. I bought a used Leica brand GLS31 carbon fiber but don’t use too much only because I haven’t found a good pole tripod with the anti crush design. I would think as a Leica user, buying any of the professional grade poles would be the way to go.
SHG
Geomax makes a great carbon fiber TVL type pole with swiss type mount. I really like my Leica GLS12 but the lack of swappable tips is a pain for some things. I can not remember ever having to adjust the GLS11. I’m looking forward to seeing the AP20
The pin holes do make a great whistle in the wind.
The only problem is they don’t make one pole with adapter’s for bayonet/5/8th thread so need pole for robot and another for GNSS.
Apart from cost it is another pole to have to carry in the truck/calibrate. Be simple for them to make an adaptor that clips on bayonet with 5/8th thread that still gives correct pole height for GNSS head. They already do for GNSS base so height hook works.
@lukenz The GAD31 is for just that purpose. The GLS12 even has a lock position for 2m GNSS operations. It also works with the standard GRT144 carrier and GZS4 tape hook for vertical GNSS measure-ups on a tri-pod.
- Posted by: @jimcox
Carbon fibre poles are light and nice when new – but I break them
With regard to weight – I’ve attached an iron rod, 5/8″ x 30″, to each leg of my bipods to add weight. Keeps them from blowing over so easily. I’m not so big on the low weight aspect. But I’m not stacking day upon day of high production topo either.
With regard to breaking rods – I instruct my people to tighten things using their fingertips only and not by grabbing a fistful of knob and cranking on it. Lightweight stuff needs to be handled with a light touch. Using the strength of the fingers only qualifies.
For GPS:
2m pole and bipod, either or metal/CF
For Bot Trimble extendable rod with pin.
I never use the GPS under 2m because well, what the hell is in the way above it if I’m lowering the GPS receiver….
The pin is stable, can get the way, and even if you’re like me and NEVER bust a rod height, and forget to update the prism height selection in Access(I have 5 prism heights based on conditions), remains at the elevation you’ve been shooting. So when you do find your “unicorn” moment of oh no, it’s at The only elevation it could be since the last change.
@norman-oklahoma
We had a few of the bipod sand bags for doing grid work. It’s a little more weight but the added dampening in wind was a great asset.
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