Notifications
Clear all

What control points do you use?

43 Posts
28 Users
0 Reactions
955 Views
JTLAPOINTE
(@jtlapointe)
Posts: 26
Member
Topic starter
 

OK so it has come to my attention this is not always the norm, but we always use a 6' traverse nail with crosshairs and dimple, with a plastic washer that reads "survey marker Do not remove" pushed through flagging. If we are set up on blacktop we use a PK set up the same way. So what I'm asking is what does everyone normally use.

 
Posted : March 9, 2016 9:10 pm
nate-the-surveyor
(@nate-the-surveyor)
Posts: 10534
Member
 

I like old engine pushrods. Good hard metal. Bury it several inches. I like going by the local scrap yard, and buying engine bolts. Flag them, and set them subsurface. Making a traverse point, that is not slightly below the surface, tends to get pulled, or "adjusted". Hide them just a bit.

N

 
Posted : March 9, 2016 9:24 pm
JTLAPOINTE
(@jtlapointe)
Posts: 26
Member
Topic starter
 

Nate The Surveyor, post: 361518, member: 291 wrote: I like old engine pushrods. Good hard metal. Bury it several inches. I like going by the local scrap yard, and buying engine bolts. Flag them, and set them subsurface. Making a traverse point, that is not slightly below the surface, tends to get pulled, or "adjusted". Hide them just a bit.

N

Our biggest problem is people read the words Survey Marker and get really bent out of shape about the " stob /stake/ corner or whatever it is they call it being wrong.

 
Posted : March 9, 2016 9:28 pm
nate-the-surveyor
(@nate-the-surveyor)
Posts: 10534
Member
 

Or, a simple 16 or 20d nail. IF there is any risk of anybody mitstaking (sic) it for the corner.... 🙂

 
Posted : March 9, 2016 9:29 pm
a-harris
(@a-harris)
Posts: 8759
Member
 

60d Nails are the universal hub and control point with a square of flag and bottle cap.

In loose ground a 1/2" x 24" rebar or better.

All control points need to be several tenths below grade and below sod when possible.

When the point is used daily, covering with a brick or tile is helpful.

 
Posted : March 9, 2016 9:52 pm

jimcox
(@jimcox)
Posts: 2013
Member
 

For cadastral surveys we use iron tubes (1" water pipe) or rods (iron re-bar, like some in US use for boundaries).

Or maybe a masonry anchor set into kerbs (but they are not good in earthquakes).

And the occasional brass plaque like this for important reference marks

Nails are used mostly for engineering work - regarded as not permanent enough for cadastral

 
Posted : March 9, 2016 10:36 pm
C Billingsley
(@c-billingsley)
Posts: 818
Member
 

JTLAPOINTE, post: 361515, member: 11401 wrote: OK so it has come to my attention this is not always the norm, but we always use a 6' traverse nail with crosshairs and dimple, with a plastic washer that reads "survey marker Do not remove" pushed through flagging. If we are set up on blacktop we use a PK set up the same way. So what I'm asking is what does everyone normally use.

Most of the time I use the same nails you're describing (mag hubs). I usually use mag nails in asphalt. When I'm cutting rebar to use for property corners, there is always a small piece of rebar left from each stick, so I keep those and use them as traverse points. If I need something to last for a long project, I will use 18" rebars with caps. Every once in a while I will still use a hub and tack, but it's pretty rare these days. In the past I have used the small roofing nails with the plastic washer that are used to nail the felt, placed in a hub. They work well if you're using a tribrach to locate your traverse points, but a prism pole will slide off of the very easily. Being a solo operator, I can make my traverse points hard to see, as long as I know where they are, and it usually keeps property owners from finding them.

 
Posted : March 9, 2016 10:40 pm
JTLAPOINTE
(@jtlapointe)
Posts: 26
Member
Topic starter
 

Our work is mostly boundary ,but we use the same type of control on all job types.We have gone to jobs that were 10 years old and recovered traverse nails.(our boss requires all work to be on state plane)

 
Posted : March 9, 2016 10:42 pm
Rich.
(@rich)
Posts: 779
Member
 

JTLAPOINTE, post: 361515, member: 11401 wrote: OK so it has come to my attention this is not always the norm, but we always use a 6' traverse nail with crosshairs and dimple, with a plastic washer that reads "survey marker Do not remove" pushed through flagging. If we are set up on blacktop we use a PK set up the same way. So what I'm asking is what does everyone normally use.

We use PKs in asphalt roads mostly. We don't put the survey marker washers because that would make it too easy for plows to pull em out. As it is, each winter the plows rack up plenty of casualties.

So I got myself a nice grinder and started putting crosses on the curbs and sidewalks.

 
Posted : March 9, 2016 10:50 pm
JTLAPOINTE
(@jtlapointe)
Posts: 26
Member
Topic starter
 

I live in West Tennessee so the plows pulling nails isn't really an issue.

 
Posted : March 9, 2016 10:53 pm

Andy Nold
(@andy-nold)
Posts: 2007
Member
 

JTLAPOINTE, post: 361515, member: 11401 wrote: OK so it has come to my attention this is not always the norm, but we always use a 6' traverse nail with crosshairs and dimple, with a plastic washer that reads "survey marker Do not remove" pushed through flagging. If we are set up on blacktop we use a PK set up the same way. So what I'm asking is what does everyone normally use.

A 6 foot nail or a 6 inch nail? A 6 foot nail would definitely be out of the norm.

 
Posted : March 9, 2016 11:26 pm
Mark Mayer
(@mark-mayer)
Posts: 3374
Member
 

I really like to put something more substantial than a nail down. The kind of projects I usually work on can go a couple years or more between initial survey and construction. So I need control to last through several freeze/thaws and be findable. It pays off. Nails and hubs are fine for temporary throw out points, but the main control needs to be iron rods, brass plugs, or the like, IMO.

Mag nails leaded into a hole drilled into concrete will last many years. Mag nails in expansion joints or asphalt are pretty hit or miss as to medium term survival.

 
Posted : March 9, 2016 11:35 pm
wgd
 wgd
(@wgd)
Posts: 127
Member
 

60d nails with flagging.

 
Posted : March 10, 2016 4:36 am
Timberwolf
(@timberwolf)
Posts: 72
Member
 

Depends on the purpose. Everything from a hub and tack for a traverse point on a lot survey to a concrete encased capped rebar stamped "survey control" on a big construction site that needs to last and be steady for several years.

 
Posted : March 10, 2016 5:29 am
anonymous
(@Anonymous)
Posts: 0
Guest
 

Here I use 6" bugle screws for most stations in dirt, or 4" ones, old bolts etc in bitumen.
Then supplement with reo (deformed bar) å?-1" diameter, 15+" long, for more permanent reference marks.
I bury them about 6" under surface (dirt not bitumen!) and put copious tape to alert others they're getting close when recovering in time to come.
I'm a firm believer in leaving my traverses well referenced for future users.
There's a dearth of old surveys here where past surveyors traverse boundaries for a mile to its terminal and leave nothing permanent, just a wooden fence post adopted as the corner. That is so irritating and not very professional.

 
Posted : March 10, 2016 5:35 am

JTLAPOINTE
(@jtlapointe)
Posts: 26
Member
Topic starter
 

Andy Nold, post: 361539, member: 7 wrote: A 6 foot nail or a 6 inch nail? A 6 foot nail would definitely be out of the norm.

6inch lol my mistake.

 
Posted : March 10, 2016 6:36 am
jason-graves
(@jason-graves)
Posts: 137
Member
 

I use MAGhubs (8" nail with dimple) on my smaller jobs along with cross-cuts in sidewalks/top of curbs and I set MAG nails in asphalt and in drill-holes on the top of curbs. If the survey is in a area of town where I have to survey the entire block for a lot survey, I make sure to set better, long term, control.

On larger farm type survey or ALTAs I will only use MAG nails in asphalt/concrete and iron pins (5/8" x 18") with a plastic cap on it, at a minimum of, every other control point.

 
Posted : March 10, 2016 6:46 am
foggyidea
(@foggyidea)
Posts: 3462
Member
 

Mag Nails in pavement, 8" Mag Nails in the ground for "quicky" jobs," Hubs with tacks for more substantial work, if I know I'm going to be back, cotton gin spindles when I can for corners in pavement, just about what ever is necessary to get the job done. I try not to rely on the traverse control to exist for long after I'm done. Usually there are enough corners in for me (or anyone else) to be able to replicate the work.

 
Posted : March 10, 2016 7:12 am
poorpdop
(@poorpdop)
Posts: 96
Member
 

Normally 60d nails set below grade, 24" irons if it's loose soil. Occasionally use PK's in asphalt, but I'm not a fan of setting control on asph unless there's little other option. For an ongoing monitoring project that we've been working on for several years, we originally set 1/2" sectional aluminum rods driven to refusal with a pneumatic hammer/drill, with permanent control casing & lid on the surface. We still have 3 of them surviving, and they are as stout and sturdy as they ever were.

 
Posted : March 10, 2016 12:28 pm
eapls2708
(@eapls2708)
Posts: 1865
Member
 

I use whatever is appropriate to establish the required stability of the point for the time period that I want that position to be useable. I've used everything from a 10d nail with flagging to 2.5" galvanized iron pipe with metal cap set in concrete. A 60d is fine as a short term control point in most situations, and a longer term point in some others, and a PK (or now, Mag Nail) can be reliable for a very long time used in appropriate circumstances, but you need to be open to a wide array of materials depending upon ground conditions, circumstances, and intended future use of the point.

 
Posted : March 10, 2016 12:50 pm

Page 1 / 3