leica 360 prism

I have a GRZ4, but it's so heavy that I rarely use it. I use the GMP101 for almost everything. The Chinese knockoffs are relatively inexpensive, but I don't know if they're built well-enough top be work the money. (That said, I bought a GRZ101 clone via eBay auction for about $13 shipped. It hasn't arrived yet - it's on a slow boat from China - but at that price I can hardly go wrong.)

I have a GRZ4 which is a really good prism.

My GPH1 prisms are Seco knockoffs.

as much as i love all that leica gear i bought, the grz4 was the weak link. not that dave is wrong, but my experience has been that whatever epoxy they use(d)- at least on the couple/three i bought- sucked. first one i had for about 8-9 months before one day leaning it on a picket fence. the weight of the rod and the DC was apparently enough that the prism and upper housing separated from the bottom housing, whole thing came crashing to the ground. had the leica shop fix it. happened again another 6 months later, and then with increasing frequency after that. no abuse, no particularly rough treatment, just came apart.

had a second one that did a bit better, but still displayed similar failures. at some point i bought a spare, as a hedge in the ever-present "time is money" equation. interestingly enough the spare didn't have the arrows painted like the ones that came with the gun, but it held up a TON better. i think it's pushing 3 years now with no issues. so... when it works (which, admittedly, is 98% of the time) it's the cat's mammaries. just don't think a 900 dollar prism should be failing that easily.

flyin solo, post: 427028, member: 8089 wrote: as much as i love all that leica gear i bought, the grz4 was the weak link. not that dave is wrong, but my experience has been that whatever epoxy they use(d)- at least on the couple/three i bought- sucked. first one i had for about 8-9 months before one day leaning it on a picket fence. the weight of the rod and the DC was apparently enough that the prism and upper housing separated from the bottom housing, whole thing came crashing to the ground. had the leica shop fix it. happened again another 6 months later, and then with increasing frequency after that. no abuse, no particularly rough treatment, just came apart.

had a second one that did a bit better, but still displayed similar failures. at some point i bought a spare, as a hedge in the ever-present "time is money" equation. interestingly enough the spare didn't have the arrows painted like the ones that came with the gun, but it held up a TON better. i think it's pushing 3 years now with no issues. so... when it works (which, admittedly, is 98% of the time) it's the cat's mammaries. just don't think a 900 dollar prism should be failing that easily.

Mine doesn't have the arrows painted.

And the offset is -11.3mm, not what Leica put on the label.

I mostly use the Trimble Active Target that came with the S7 now because unless it is selected the S7 will not shoot it. When it is selected then the S7 can't see the prisms I usually have setup around the area.

I used GRZ4 with my old S6 which would still shoot it if I forgot to change the prism in the TSC2. It could be edited but it's aggravating to deal with. And I had to constantly watched to be sure I wasn't unknowingly taking 200 topo shots to the backsight.

flyin solo, post: 427028, member: 8089 wrote: my experience has been that whatever epoxy they use(d)- at least on the couple/three i bought- sucked

These were genuine Leica products? Because I recall reading some Leica literature pointing out that the knockoffs used inferior glue and were prone to coming apart.

Jim Frame, post: 427031, member: 10 wrote: These were genuine Leica products? Because I recall reading some Leica literature pointing out that the knockoffs used inferior glue and were prone to coming apart.

Well, they came in the case with the D.C. When I bought the rigs. I paid for GZR4 per the invoices. And they say "Leica" on em. Not saying they are, but I always assumed as much.

GRZ101 is a great prism but will not reliably work with "powersearch" on the Leica instruments that have it (most of the newer ones).

I had to replace one a few years ago ( I don't remember why) but I think it cost about $900 at Leica of Georgia.

I had some issues with a knock off GRZ4 coming apart, glue didn't fix the problem as some of the reflective material became displaced when the prism initially came apart, tracking issues. Ended up picking up another knock off, below, no problems, power search works well with it as long as you are reasonably close targeting Z angle wise, approximately 30'+/- in 300 feet, better results might be achieved by modifying the PS criteria but I'm a sucker for punishment and tend to just get used to things as they work so that hasn't been tested.

http://www.ebay.com/itm/360-degree-CPIII-Total-Station-Prism-for-Robotic-Total-Station-/262770504968?hash=item3d2e57b508:g:Q8sAAOSw-0xYWPsC

flyin solo, post: 427038, member: 8089 wrote: Well, they came in the case with the D.C. When I bought the rigs. I paid for GZR4 per the invoices. And they say "Leica" on em. Not saying they are, but I always assumed as much.

The Leica logo isn't a guarantee of provenance, as the Chinese are adept at counterfeiting. For example, this prism can be had for $140 shipped on eBay:

The REAL deal for the ATR/Power Search functionality is about $990 for new. DON'T cut corners...

MPR 122 Leica 360

Don't get anything else all else is garb

One more time
MPR 122

1 Tough
2 good centering.
3 gps threads on top
4 i can say its perfect

Peter Kozub, post: 427071, member: 375 wrote: MPR 122 Leica 360

Don't get anything else all else is garb

One more time
MPR 122

1 Tough
2 good centering.
3 gps threads on top
4 i can say its perfect

GPS threads (5/8") on bottom as well. (It is intended for machine control).
Good compromise between size and performance.

Hi All

Leica should ...or try to use titanium for MPR 122 Etc.....

on all rod based components use titanium threaded metal fixtures and Machine control for Mpr 122

other than that how could the weight be reduced ???

and still be tough for day to day survey / Lite

Looking for the MPR122 T1 any day Now T1 = Titanium

Pete

The knockoff GRZ4s say Leica on them, but never have painted arrows...and the real ones do. If it came apart, it's counterfeit.
That said, if you're thinking of going Leica then I highly recommend looking at GeoMax / Carlson: The Zoom90 is identical to the Leica TS15 and priced much better. Major bang for the buck! Call me - 866-877-8783.

Jim Frame, post: 427059, member: 10 wrote: The Leica logo isn't a guarantee of provenance, as the Chinese are adept at counterfeiting. For example, this prism can be had for $140 shipped on eBay:

1. I bought Leica gear from a Leica dealer that all came together in Leica cases and boxes. Not sure just how much forensics work I'm expected to do to guarantee the authenticity of the gear.
2. A likely scenario is that Chinese knockoff prism is exactly the same product as a genuine, certified Leica product. Chinese factories have been known to DIY with the sales of products they manufacture for others- just ask anyone who works in the bicycle industry. You can often buy the very same product on eBay for pennies on the dollar, the only thing it doesn't have is the insurance policy and bank account from which you can sue for damages.

I have been using the GRZ4, GRZ122 & GRZ101 for years without any troubles in workmanship. The GRZ4 dates back to the late 90's and has held up through a lot of adverse conditions. The GRZ122 costs a considerable amount more but for that money you get the same precisions at any angle and the ability to mount a receiver on top. If I recall correctly, the 122 has a solid bar running through it. The ability to mount the receiver on top saved my bacon this week. Walked out of the office with the wrong GS14 case and did not have a GAD with me to mount on a Leica post. Before I started to drive back to the office I remembered that I could use the GRZ122. The GRZ101 mini is great and has the best precision of the 360's but for some reason power search never seems to find it.

Thanks for all the great comments. Certainly if you are selling a 360 prism for $140 when others are selling the same 360 prism for between 900 and 1200 there must be some meaningful difference. I cannot image that the cheaper prisms provide same precise results from all the faces as the more expensive prism... same prism constant no matter which face returns the signal...". That is more important to me than the epoxy not lasting.... anyone ever test and compare prisms....

Hey mate,
I was using a GRZ4 prism for 8 years until recently without any build quality issues. It had been dropped on concrete, dropped in the water, dragged through the bush and still returned the same consistent measurements. Nobody else that I work with has ever had any issues with them either, and if you were to have one break on you I'd assume that some kind of warranty should be in place. As John Putnam stated above the GRZ122 has a solid metal bar running through the centre of the prism, which is in place to support the extra stress imposed by a GPS antenna.

Before chopping and changing your prisms consider how it will affect the tracking and measuring performance. Alot of the manufacturers claims are only legitimate when using their accessories, so you may find that you'll need to tinker a bit to achieve the same accurate results as stated, and the robotic tracking behaviour may change significantly when not using an original accessory.