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Spikes are cheap

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(@williwaw)
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But setting up on the wrong one sure isn't.

I've gotten in the habit last few years, before I set a point to tie something, take a minute and sweep the area with the schonstedt. Doing a design survey earlier this week and spot a survey advantageous hill over looking my little area of interest. Perfect place to set the S6, nice commanding view. Get up there and before I slam a spike in the ground, said to myself, 'if I like this spot, more than likely someone else did to'. Sweep the spot with my schonst and low and behold, three spikes within 5' of where I was going to set mine.

Does that qualify as a pin cushion?

 
Posted : May 1, 2015 12:01 pm
(@brad-ott)
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:gammon:

 
Posted : May 1, 2015 12:23 pm
(@surveyor85)
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Now that's experience!

 
Posted : May 1, 2015 12:31 pm
(@nate-the-surveyor)
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Pull all 3 of them.

Set your own. Bury it deep.

(that's the stuff nightmares are made of)

N

PS, that was a really bad joke. Happy friday to all.

N

 
Posted : May 1, 2015 12:38 pm
(@dave-ingram)
Posts: 2142
 

That's just right for a mistake by somebody that doesn't check measure to a backsight or two.

 
Posted : May 1, 2015 12:46 pm
(@williwaw)
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Funny you should say that. I spent a good part of the last couple days trying to pinpoint the source of a 7' bust in a survey I inherited from my predecessor done in 2004 I was using to get going on another survey. My conclusion? When they returned to the site some months later the instrument man set up on another spike 7' away and from what I can tell, just by pure (bad) luck, the back sight check was close enough to what it should have been that they didn't catch it. :-/

 
Posted : May 1, 2015 12:55 pm
(@a-harris)
Posts: 8761
 

You are not alone.

I've found 60d nails from several feet to within a foot of my 60d nail from the past survey.

It is a necessity to do a radial stakeout to and including the BS and several FS from the previous survey to make certain that you are actually occupying your old hub.

Shortcut party chiefs have cost me many hours of driving back to the scene to verify what they actually setup on because they did not take time to shoot any of the previous located feature and/or monuments as a check.

:good:

 
Posted : May 1, 2015 12:56 pm
(@kent-mcmillan)
Posts: 11419
 

> But setting up on the wrong one sure isn't.

No, it isn't. That's why I think setting spikes with aluminum washer-discs stamped with the point i.d. no. and professional identifiers is well worth the extra money.

It pretty much eliminates the possibility of misidentifying a control point and makes it possible to return to a site years later and do further work with very little fuss or muss.

 
Posted : May 1, 2015 2:33 pm
(@williwaw)
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That is a very good way to avoid confusion. Problem with using washers around here is the ground is frozen half the year and even when it's not, I typically set points below grade by as much as .2' to avoid them getting scraped out by snow plows or otherwise disturbed. Driving a point down below grade through frost with a fat washer on it might prove a bit challenging. I do like the idea in concept though.

Setting points deep like that also has another advantage. My first survey I ever did from start to finished drafting was part of a land exchange for an alcohol recovery center. The new neighbors were very hostile to the whole idea. I had all my control points set down .1-.2'. My standard MO. I came back on the job to set the monuments and did a back sight check and found a huge discrepancy. Looked closer at the point I was occupying and it was flush with the ground. The SOB had come through after I left and moved 90% of my control points. Didn't yank them, just moved them 5-10'. Had to re-survey in every single one of them. I bury my points deep and I don't make them obvious.

 
Posted : May 1, 2015 3:06 pm
(@bill93)
Posts: 9834
 

5-10'

Be glad he wasn't smart enough to move them 0.3, 0.6 and so forth to let you get mostly done before discovering the discrepancies.

 
Posted : May 1, 2015 3:53 pm
(@sir-veysalot)
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Yep. Been there done that. Lukily I always shoot my backsight. good thing the distances weren't close

 
Posted : May 1, 2015 4:56 pm
(@brad-ott)
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> 5-10'
>
> Be glad he wasn't smart enough to move them 0.3, 0.6 and so forth to let you get mostly done before discovering the discrepancies.

Devious.

 
Posted : May 1, 2015 6:11 pm
(@kent-mcmillan)
Posts: 11419
 

> That is a very good way to avoid confusion. Problem with using washers around here is the ground is frozen half the year and even when it's not, I typically set points below grade by as much as .2' to avoid them getting scraped out by snow plows or otherwise disturbed. Driving a point down below grade through frost with a fat washer on it might prove a bit challenging.

The washers I use are 2 in. dia. Obviously frost isn't much of a problem in Central Texas and a good bit of my work is done on sites where the spike is driven (with washer) into a hole drilled in solid or weathered limestone. I'd guess that the frost depth in Alaska is significantly greater than 0.2 ft., but if for some reason I'm wrong about that, you'd just use a 2 inch mandrel (such as a 2 inch pipe nipple with caps on both ends) to make a hole into which to countersink the spike and washer.

I give the spikes I set a centerpunch, so the last operation is whacking the spike a sound rap or two with a hammer via a punch. In soft soils, that by itself can countersink the spike and washer at least 0.1 ft.

 
Posted : May 1, 2015 7:24 pm
(@ravelode)
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I dimple all of mine with a drill bit so the rod point is always in the same spot and I use 120d ring shank spikes and I use blue flagging under the head and pink whiskers in grassy areas.

 
Posted : May 5, 2015 6:16 am
(@nate-the-surveyor)
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decoy method

I have even removed all flagging from my control points, and then flagged bogus flagging some feet away, to serve as decoys. Covered my control points with gravel, and grass.

N

 
Posted : May 5, 2015 6:34 am
(@joe-nathan)
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Here is a funny one:
One day I pulled up near one of our job sites to check up on one of our crews. We were up in N. LA working on one of our many shale unit wells. Well I pulled up to the base and low and behold there are three units running (on being ours, the other two competitors) on three different control points all w/in 20 feet of each other. All of them R8's. This spot was on a tree less high point on the side of the hwy with a pull out (rare in N. LA pine woods).

Luckily our control points have our cap on it. I think one of the other control point had their company cap on it to.

But it does happen that a crew will set up on the wrong control point. Sometimes it is due to laziness of the crew not setting a check point far enough away. Luckily we have our unit set up to run static while surveying. Also having a proper control point reference sheet will help prevent this.

 
Posted : May 5, 2015 6:42 am