Sign in to follow this  
Followers 1
Gungadoy

U.S. Coast & Geodetic Survey Disks Pics

102 posts in this topic

Happy 2016!

I spent a nice S. Florida sunny afternoon trying to find two benchmarks, BIRD & SMOKE, on an Everglades levee road. The levee's go on and on for miles often with a bunch of triangulation stations together with their two reference mark disks.

Even with a metal detector, I only had limited success. I was able to find a broken off disk stem at one of the reference marks. At the other I found one reference mark disk and a cut-off metal witness post. Link to BIRD

97d61ea4-2c02-42b3-9e6e-a9aeb19be0b8.jpg

Link to SMOKE

ae821c78-a423-4e6a-8f50-184bf7170558.jpg

Edited by Gungadoy
0

Share this post


Link to post

Nice job! Everything's frozen solid in Ohio right now--I'm hoping to do some detecting when spring comes.

0

Share this post


Link to post

I've been having a run of bad luck lately. I like recovering Triangulation disks, their reference marks and azimuth disk but they've either been missing or I just can't locate them. Oh well, what's one more DNF!

I found this RM on a cool boulder along a canal on S. Florida's SR27. Exposed to the weather for 50+ years it certainly did tarnish a lot. AD7338

 

85d99a48-a597-42d3-93dd-5d5c4e66f0dc.jpg

Edited by Gungadoy
0

Share this post


Link to post

I liked the way that this disk has actually been fitted to the rock it was attached to by tidal action since 1941. This is TR1620(BIGHT 1941) in Port Townsend, Jefferson County WA.

1fa7508c-ef2e-417b-b89a-f7364d16f3df.jpg

Edited by shorbird
0

Share this post


Link to post

Haven't been finding too many USC&GS disks lately. I've been working on recovering AD7220. I was surprised to recover Reference Mark 2 so easily on the surface. Now I have to return at a time when there's less traffic in the area. The station mark appears to be borderline on the homeowners property line & front lawn.

 

Has anybody been finding any USC&GS disks around the country?

 

c4c518f9-56c3-4860-a88e-1cbda77bc9f7.jpg

64aee3d1-716f-430b-8b84-69c95d3600df.jpg

0

Share this post


Link to post

Hey y'all! I just had a question. I very rarely find benchmarks while I'm out geocaching but I stumbled across this one yesterday. Can someone tell me what it is?

 

image_1.jpeg

 

It looks like it says U.S.E.D. Now does that mean it's an elevation disc or just a used disc? It's planted in a very large (20' dia) concrete base and near it was a metal pedestal with a large round top that had a huge metal screw in the middle. This was about halfway up the hill side over looking the C&O Canal NP and the Potomac River. We found this one too behind a lock tenders house.

 

image_2.jpeg

 

This is at Great Falls NP in Maryland and about 14 miles upstream from Washington DC. I'd love to find more of these. Is there an easier way to search for the coordinates other then using the NGS website? I've tried a few times to see if there were any around where I have been caching but I've had a hard time trying to find any coordinates for any of them. This one was is pretty close by and other then the weather, probably won't be disturbed much.

 

image.jpg1.jpg

Antietam National Battlefield

0

Share this post


Link to post

Your 1990 triangulation station is JV6502, last logged in GEOCACHE almost a year ago. USED is the United States Engineer Department, also know as the Corps of Engineers (COE, also USACE).

 

When you request help here it is nice to give us at least an estimated Lat/Long. If you are not using an HH2 (hand held GPSr) it is possible to pluck an accurate as L/L from Google Earth.

 

Enjoy the search. kayakbird

 

PS: I got that PID by entering Antietam, MD in the search block of the

 

National Geodetic Survey Data Explorer

 

MEL

Edited by kayakbird
0

Share this post


Link to post

Howdy everyone:

 

Since there was a good discussion about USCGS+SS discs, an easily located example is CW7120 in Brandon, FL just outside Tampa. Its located off SR60 and Pinewood Ave. There are plenty of fascinating benchmarks all around Brandon. I have photos but will have to dig them out.

 

/greyfox

0

Share this post


Link to post

Greyfox, this is the place. Yes, the CGS+SS disks are pretty cool disks. Post some CGS disk pictures.

Edited by Gungadoy
0

Share this post


Link to post

Gungadoy,

 

The number of USC&GS disks you find is usually related to the part of the country you are in. In some areas, there are plenty of them and in others, not so much. In Florida, there seem to be a large number of county and state disks. There are quite a few USC&GS disks along the coasts, along A1A on the east coast and 41 on the west.

 

shorbird

0

Share this post


Link to post

Look for this in the datasheet: RD0305_MARK LOGO: CGS+SS, RC0876_MARK LOGO: CGS+SS

 

Note - these two are in Oregon, not all (maybe only a few) have this line. Many others in Oregon have zero information that will float to the top with GSAK filters. Increases the pleasure of the hunt. MEL

0

Share this post


Link to post

What program is used to find U.S. Coast & Geodetic Survey Disks? I have used a couple different apps, but they have more than the disks so it gets kind of confusing. Wish the geocache app would map benchmarks better. It only lists them without the map. I always take a picture if I stumble across a disk.

Edited by CGTeri
0

Share this post


Link to post

One thing you can do is just click on find all nearby benchmarks for geocaches you are going after. That brings up a long list of all types.

0

Share this post


Link to post

What program is used to find U.S. Coast & Geodetic Survey Disks? I have used a couple different apps, but they have more than the disks so it gets kind of confusing. Wish the geocache app would map benchmarks better. It only lists them without the map. I always take a picture if I stumble across a disk.

To best help you it's best to find out what programs and apps have you used?

I use the old Hunt Markers and Findacontrol app on my iPhone. Plus the NGS webpage, NGS Datasheets to pull up the datasheets and load them into GSAK for sorting.

0

Share this post


Link to post

Howdy everyone:

 

Since there was a good discussion about USCGS+SS discs, an easily located example is CW7120 in Brandon, FL just outside Tampa. Its located off SR60 and Pinewood Ave. There are plenty of fascinating benchmarks all around Brandon. I have photos but will have to dig them out.

 

/greyfox

 

There are tons of the USCGS & State Survey marks in the Upper Penninsula of Michigan. I search mainly in Houghton and Keweenaw Counties, and have found around 20 of them. There are many more that I haven't bothered to look for. Here is one of my favorites: FHCnEdu.jpg

 

Someone tried hard to pry it out but this was one stubborn mark! Looks like that spike has been there for a few decades. "Bumbletown" is a pretty cool name as well - it's a nearby place name. Some of them are easy to find along roads and highways, but the better ones are in some pretty remote locations that require some good hikes.

0

Share this post


Link to post

Lots of thorns around that one as I recall. Was there in 2001. We were doing a GPS project on US-41 from Holiday gas station to Mohawk to tie down US-41 ROW. I drove close to that station with my 4x4 suburban but almost did not make it out, muddy road.

 

PS - One of the guys I use to work with was born in Bumbletown circa 1933-34, around the time of the work.

Edited by Z15
0

Share this post


Link to post

Lots of thorns around that one as I recall. Was there in 2001. We were doing a GPS project on US-41 from Holiday gas station to Mohawk to tie down US-41 ROW. I drove close to that station with my 4x4 suburban but almost did not make it out, muddy road.

 

PS - One of the guys I use to work with was born in Bumbletown circa 1933-34, around the time of the work.

 

I went to this one last summer. Lots of recent logging in the area so we couldn't drive very close and had to walk in. Even that was tough - the loggers really leave a mess behind. Fortunately this is up on top of an elevated rock outcrop so its probably pretty safe from accidental destruction - if not vandalism.

0

Share this post


Link to post

RFI: PID? Link to Log? These being about my #3 favorite sub-set, I'd like to get a few more - even vicariously. kayakbird

0

Share this post


Link to post

What do you think of my collection?

 

s9JWblU.jpg

 

Very nice. Do you touch them up with Brasso every few days? kayakbird

0

Share this post


Link to post

The photo of my collection isn't exactly what it seems to be! Here is another...

 

k48Yzsa.jpg

 

I'll take it as a compliment that the first photo passed as a photo of full size benchmarks :)

 

Since it would be extremely difficult (and most likely very costly!) to find un-stamped examples of these without raiding the collections found in some NGS or USGS Office building, I've been recreating these in miniature myself. I a graphics package and 3D modeling software along with references such as George Leigh's document, historic USC&GS and USGS Publications and bulletins, measurements of actual benchmarks provided by some helpful contacts at NGS and USGS, photos found online, as well as my own photos, measurements and rubbings of benchmarks I have found. Once I have created a good 3D model I have bronze castings produced from the 3D Printing service provided by Shapeways.com. The end product are scaled down to roughly 1" diameter for the standard USC&GS disk. The USGS Benchmarks are slightly larger and the State Survey is significantly smaller. They arrive from Shapeways as bright and shiny bronze so I use various techniques to give them a more aged bronze patina like we find on benchmarks in the field. This also helps accentuate the very fine engraved text (The small letters in the inner ring of text are 1mm high!). 3D Printing really produces amazing results. I think Shapeways is even surprised by the small text that comes out readable -whenever I send them a new model to print they tell me it's to detailed, but I talk them into proceeding and you can see the results.

 

My goal is to recreate all of what I think of as the "classic" Coast and Geodetic Survey marks used from 1900 to the early 1970's before the designs started to change under NOAA. I'm also planning on modeling several USGS benchmarks from the same era.

 

I've also done some of these as keychains with the accurate stampings of specific benchmarks.

 

1z9aDyi.jpg

0

Share this post


Link to post

Really sneaky neat! How about a flared rod? Very few of which are out there in the wild.

 

I think that the nail with your Bumble Town &SS was placed like that for finding under a snow drift. kayakbird

0

Share this post


Link to post

Phenomenal work! It must take a serious investment of time to get the detail right, and a not insignificant production cost.

 

It reminded me of the equipment models a guy posted on the professional surveyors forum. He also makes practical things for his work.

https://rplstoday.com/community/threads/more-printed-surveying-models.241503/

https://rplstoday.com/community/threads/got-my-1-4-scale-geodimeter-today.232161/

https://rplstoday.com/community/threads/i-received-my-christmas-ornaments.227217/

Edited by Bill93
0

Share this post


Link to post

I've been working on them for about a year and a half I think. It's gotten much easier! I just sent in a flat top reference mark. I'd like to do the cap type that fit over the end of a big pipe next and a USGS benchmark that has a twisted stem. That has me puzzled so far.

 

I bought a Wild T3 and tripod model from the guy that was mentioned. That was one of my inspirations to try Shapeways myself. I've made all the models in the picture available on Shapeways, so if anyone wants one you can get one there. They can be customized with stamped station names and years also. Not sure if I can post links here so just google Shapeways survey benchmark and you should find it.

0

Share this post


Link to post

I wish they were $10 also! 3D printing is pretty amazing and it make it possible to make something like this for a relatively low cost for a one off, but it doesn't really scale well,

 

I'd be interested to hear opinions on what people would consider a fair price for them.

0

Share this post


Link to post

Very, very cool. Thanks for sharing this on the forum.

I'd probably buy a few since these are my favorites; however 40 is a too steep for a another trinket that'll sit in my drawer alongside my geocoins.

0

Share this post


Link to post

I would gladly pay $10 each for them (and would probably buy one of each at that price). I am not saying that is a fair price... just what I would easily spend. If they were $20 I would consider a few. I still may bite at the listed price, but I have to think about it a bit.

0

Share this post


Link to post

Posted (edited)

Happy New Year everyone!

 

I have reduced the prices by lowering my markup to just a couple dollars over the base cost that Shapeways charges to produce these (Shapeways determines the base price using the size and volume of each piece as well as the material used).

 

The domed C&GS disks with stems are now $33. The hex shaped gravity disks are $35 because they are slightly larger. I just added a flat topped reference mark which is $40 because it has a much higher material volume due to the thickness of the flat topped disk and a much larger stem style. Keychain and stemless styles are now $28. The USGS marks are $30-$35 depending on the style of mark.

 

Since the keychains are slightly cheaper than the full stem marks I'd recommend them to anyone interested in getting one of these who is concerned with the cost. They look nice on my keychain and hold up really well to the wear of rattling around in your pocket with keys and loose change since they are solid bronze , not the lower quality metals other replicas are made from. They really have a nice heft to them. The keychains are also a lot easier to enjoy and show off to friends since they are with you all the time and not gathering dust on a shelf or drawer with other trinkets :). I only have a few disk styles as keychains so far (triangulation station and reference marks), but I can easily turn any of the disk styles with stems into a keychain. Just let me know what you might want to see.

 

Also, Shapeways occasionally runs promotions for free shipping or a percentage off orders of a certain material. I can post those promotions when they come up if anyone wants.

 

Here are some photos of the new flat topped reference mark:

W0BmOBb.jpg

DpxjGog.jpg

AMuI0XK.jpg

Edited by Amygdaloid
0

Share this post


Link to post

Found this Magnetic Station in Lubbock, TX in 2015. Many others also found it while attending a mega Event. Short mowed grass made it easy. GC.com had it listed as a Triangulation Station. Next time I'm there, I'll try for the RM and AZ marks.

DP 0673 LUBBOCK MAGNETIC STATION

f494f9c6-8edb-497d-aae1-7d53a289b523.jpg

0

Share this post


Link to post

These steel USC&GS BMs were placed in 1945. My guess is, like the steel penny, there was a shortage of copper for the war effort.

AH0842 W 920 Bench Mark. Found several between Kingsville and Corpus Christi, Texas.

Some are disappearing as the concrete culverts are being replaced.

https://s3.amazonaws.com/gs-geo-images/a664c13d-98c2-4275-9b93-47c865f2f9da.jpg

 

Edit to add sentence.

Edit PID Typo. thanks kayakbird in following post.

Edited by 8Nuts MotherGoose
0

Share this post


Link to post

These steel USC&GS BMs were placed in 1945. My guess is, like the steel penny, there was a shortage of copper for the war effort.

AH0482 W 920 Bench Mark. Found several between Kingsville and Corpus Christi, Texas.

Some are disappearing as the concrete culverts are being replaced.

https://s3.amazonaws.com/gs-geo-images/a664c13d-98c2-4275-9b93-47c865f2f9da.jpg

 

Edit to add sentence.

Link to previous thread 'Wartime "Shortage" Disk?: http://forums.Groundspeak.com/GC/index.php?showtopic=203716&st=0&p=5101393&hl=iron%20disk&fromsearch=1entry5101393

 

Also slight typo in above PID - should be: AH0842.

 

Spent a bit of my younger days at NAS Beeville and later at NAS Kingsville. Drove the Chapman Ranch Road a few times. Wife & I were driving home from a great Mexican Restaurant meal in Corpus with two other couples and stopped to listen to the first footsteps on the moon. kayakbird

0

Share this post


Link to post

These steel USC&GS BMs were placed in 1945. My guess is, like the steel penny, there was a shortage of copper for the war effort.

AH0482 W 920 Bench Mark. Found several between Kingsville and Corpus Christi, Texas.

Some are disappearing as the concrete culverts are being replaced.

https://s3.amazonaws.com/gs-geo-images/a664c13d-98c2-4275-9b93-47c865f2f9da.jpg

 

Edit to add sentence.

Link to previous thread 'Wartime "Shortage" Disk?: http://forums.Groundspeak.com/GC/index.php?showtopic=203716&st=0&p=5101393&hl=iron%20disk&fromsearch=1entry5101393

 

Also slight typo in above PID - should be: AH0842.

 

Spent a bit of my younger days at NAS Beeville and later at NAS Kingsville. Drove the Chapman Ranch Road a few times. Wife & I were driving home from a great Mexican Restaurant meal in Corpus with two other couples and stopped to listen to the first footsteps on the moon. kayakbird

 

I edited the typo and gave your sharp eye the credit.

Thanks for posting that previous thread. A good read.

NAS Kingsville is still active. I hear them taking off whenever I'm in town.

0

Share this post


Link to post

Has anyone found or have a PID for a found example of a C&GS Triangulation Station pipe cap like shown in this illustration from Special Pub 11? I see lots of found BM caps from this time period (thanks kayakbird!) but I've been searching for photos of these with no luck.

 

IDZQK1x.jpg

0

Share this post


Link to post

Has anyone found or have a PID for a found example of a C&GS Triangulation Station pipe cap like shown in this illustration from Special Pub 11? I see lots of found BM caps from this time period (thanks kayakbird!) but I've been searching for photos of these with no luck.

 

IDZQK1x.jpg

 

Amygdaloid,

 

Not real sure that the below link still works. Same photo is used there [page 10, figure 23], but no information on actual recoveries of same. Did research a few named CGS tri-points in Montana, Arizona & Wyoming back in those years & all I came across was a bogus GEOCACHING found nail that replaced a disk. Heads up TillaMurphs. kayakbird

 

http://www.ngs.noaa.gov/web/about_ngs/history/Survey_Mark_Art.pdf

 

Link seems to work - added page/figure number. MEL

Edited by kayakbird
0

Share this post


Link to post

Did some more google hunting this morning and found two Triangulation Station caps on Jerry Penry's website. Both were set in South Dakota in 1925. I would have thought these cap style would have been used much earlier like the BM caps.

 

I know I have looked at these on Jerry's website before but the significance of the caps hadn't dawned on me at the time. Now back to the hunt!

 

Here are some links for these two stations:

 

BEAR PU2319

 

Jerry Penry Photo:

bearbutte15.jpg

 

Jerry Penry's page on Bear Butte

 

CUSTER PU2338

 

Jerry Penry Photo:

custerpeak4.jpg

 

Jerry Penry's page on Custer Peak

0

Share this post


Link to post

Hey, Thanks for those links. Mr. Penry does do a fine job! I think that I have seen all his MORC rehab recoveries.

 

Will have to go back to GSAK and research through the 1920's. kayakbird

0

Share this post


Link to post

I just read through a bunch of station description from the Texas-California Arc (special pub 11) and they used the Triangulation Station pipe caps pretty frequently. They even used the old cup style in at least one case. I wasn't able to find any that have been recovered since the 70s though. A lot of them are located out in the middle of nowhere in the Texas and Arizona desert so I wouldn't be surprised if a couple could still be there. Being a native of the Midwest I've never had the chance to look for anything in that kind of terrain. I can't help but imagine ending up in the desert scene from "No Country for Old Men" if I tried to recover one myself!

0

Share this post


Link to post

This jogged a memory. In Sept '14 we biked the length of the Mickelson Trail through the heart of the Black Hills. The trip started, though, with a hike to the top of Bear Butte. I took a couple of photos of the station at the top of the hill but I forgot to follow up and log it (it was pretty beat up and there have been multiple destroyed marks up there.) I was pretty sure it was PU2319 as it was visible through the plexiglass under the observation tower as described in the 1984 NGS recovery note.

I just pulled up my images (taken through the plexiglass) and with some processing I am able to make out the 1925 (double strike on the 2) and an "E" above left of the apex of the triangle. That's good enough for me, time to log it.

 

c71eeaa9-088a-4f20-9faa-f27b84cc5827.jpg

 

93d258d4-f9e8-4974-a75f-8f90bce2b77b.png

 

Edited to add: I cannot see an access hatch on J Penry's page but I recall looking through it

Edited by Michaelcycle
0

Share this post


Link to post

Great historical thread going here! Threaded pipe cap were also used in the first decade of last century along the Medicine Line by the International Border Commission (IBC).

 

IBC Threaded Pipe Cap

 

7359f07d-5ec1-4c43-8e62-5f5845ed150e.jpg

 

This find/post from the first decade of this century is a bit unique.

 

IBC Pipe Cap in Utah

 

46fe6f3d-fb41-4de1-9d3b-43b748bdb9e6.jpg

 

Good weather for computer hunts here near the center of Montana. kayakbird

Edited by kayakbird
0

Share this post


Link to post

I found an 1895 Mississippi River Commission pipe cap the other day - ST PAUL FRONT BASE, PID DO1622. It's pretty unique, more of a pipe plug actually as it fits inside the pipe and is attached to the pipe with 2 square head "bolts" through the sides. It is made of cast iron with raised lettering. What's really interesting is there is a square section of the face that seems to be brass or bronze imbedded into the cast iron that was intended for the stamped markings. I used a magnet to verify that the main body is iron and that the bright square is not magnetic. The two "bolts" attaching it to the pipe are also not magnetic - you can see the green patina on the one in the photo. Other than a chunk broken off the edge it's in good shape for a piece of iron out in the elements for 120 years. I think they made better metal back in those days. The pipe itself has some large rust holes near the the ground surface however.

 

This was only about 3 miles from my house but I never knew it was there. I've been driving by it for 25 years. It's not in the geocaching benchmark data, and in the NGS data sheet lists it as an unstamped Bolt for some reason. I turned it up using my time enabled map.

 

Not surprisingly, I think Kayakbird has logged some of these Mississippi River Commision marks as well.

 

FoQGQnc.jpg

0

Share this post


Link to post

Amygdaloid, all,

 

I do have several of the MIRC's but none with the raised lettering cap.

 

b88432a6-05b2-4b7a-afb9-b97935e273e2.jpg

 

Below note was added to my 2009 find of WYE CAP (SK0178 WYE BOLT UNDER)

 

"

Just found this note in Special Publication # 18. Kind of clears up in my mind that these are very similar to the Missouri River Commission tri-angulation stations set in the 1880's - a buried stone and a stand pipe to which a distinctive cap is attached.

 

NOTE 48.-The bench marks in the line Fort Adam S to Vicksburg, 1905-6, were said to be “the regulation tile * pipe and bronze cap used by the Mississippi River.

Commission for some years.’’ They were therefore of the same type as those described in the Report of the Chief of Engineers for 1900, Part 7, as follows:

“The new precise bench marks established on lines Biloxi, Miss., to New Orleans, La., and Baton Rouge, La., to Fort Adams, Miss., are of the B. M. form used

in 1898 above St. Paul, Minn., for ordinary bench marks, and consist of tile and pipe as follows: A vitrified tile 18 by 18 by 4 inches, in the center of which

is set vertically with lead a three-eighths inch copper bolt, the upper end being a little above the upper surface of the tile. Surrounding the bolt on the

surface of the tile is the inscription,‘Mississippi River Commission, 1898, U. S. B. M.’ This tile is buried in the ground about 3 feet beneath the surface.

On top the tile is placed a 4-inch wrought-iron gas pipe 4 feet long, concentric with copper bolt; the lower end of the pipe is split into quarters and spread

out to prevent its being pulled up. A cast brass cap fits over the top of the pipe and is riveted thereto. The cap has the following inscription in sunken letters:

‘Mississippi River Commission, $250 fine for disturbing this mark, 1898, **'P' U. S. B. M. U. S., latitude [ ],longitude [ ],elevation above sea [ ].’ The **P is put on with a prick punch. The elevation of the top of the cap is determined; the structure has thus two bench marks.”

 

THIS COMMA MISSING IN SP #18.

**The P appears to factory on the two that I have seen,

 

Now I would like to see at least a picture of one of the leaded bolts."

 

Datasheet treatment on these two part monuments is not consistent in either survey. *NOTE* 'BOLT" generally means a short stub of non-threaded copper rod leaded into a placed stone or chunk of concrete or native rock. kayakbird

 

kayakbird

0

Share this post


Link to post

Thanks for that info kayakbird. I hadn't thought about the possibility of a bolt at the bottom of the pipe. Now I wonder if the bolt might be visible through the rusted out hole in the side of the pipe? Probably need one of those inspection cameras. Probably covered up with debris.

 

I did some research on the Mississippi River Commission and found scans of the maps they produced in 1895 for this area. Really amazing maps. Here is a link to them: MRC Maps

 

Below is a snapshot of the map around the Front Base mark. Note the 2 elevations labeling Front Base, one for the bolt, the other for the cap, about 4 feet difference. The pipe is about a foot above the ground so that puts the hole about 3 feet above the bolt. I may take a tape measure or stiff wire out to it and see how deep it is to the bottom 😊

 

To the south west is Back Base, so I presume the two marks are part of a baseline. Unfortunately Back Base is now in the middle of one of the taxi ways in front of the Minneapolis-St Paul International Airport terminal. I'm curious what the "Sun Dial Post" at the bottom of the image was. That area is now under the airport access road. Many of the buildings labeled "Officers Quarters" and "Soldiers Barracks" still exist however. I suspect "Front Base" and "Back Base" may have been triangulation stations given the triangle symbol on the map and on the cap. The map uses the same triangle symbol for other points that I believe were triangulation stations.

 

There are other benchmarks shown on the map, so now I have some more investigation and research to see if any exist still. Ford Dam is just upbstream from here so many may be deep underwater now, or wiped out by the floods that frequent this stretch of the Mississippi. In any case it's fun to discover this practically right in my back yard and in the middle of a big city.

 

KLNcGih.jpg

 

Here is a note from the map that confirms what kayakbird said about the bolts in his previous post:

 

7d8gFPg.jpg

 

And here is another similar MRC mark 20 mile away that I'll have to visit now; Hastings PP2451

0

Share this post


Link to post

Amygdaloid & all,

 

Due to good mentors, river erosion, field cultivation, Survey Grade GPS, land owner permission at a NONPID and dumb luck probing at a shallow set with a short screwdriver, I have been fortunate to touch six of the MORC stones. Several others have been visible down the pipe.

 

This one was not so lucky. kayakbird

 

MORC NB

 

a2350a74-d0ad-4ae6-855d-4d1b58b8235c.jpg

0

Share this post


Link to post

For anyone who has found a US Coast & Geodetic Survey cap, did you happen to measure the diameter of the cap, or could you at least confirm if it is a larger diameter than a standard disk? I have never found one so I'm looking for the dimensions so I can model it in 3D. The old reports say they are made to fit a 3" pipe, but in other respects are exactly similar to the disk stations, which are about 90mm diameter. A 3" pipe has an OD of 3.5" (or 89mm), so a cap that was 90mm like the standard disk could would not work as a cap. I have measured a USGS BM Cap from the same era and it has an OD of about 3.9" (99 mm) and the pipe it was on was probably around 3.5" diameter, so is the USC&GS cap of a similar pattern?

 

The photos of the caps in the old bulletins look like they are the same diameter as the disk in the same picture, so I'm wondering if the flat top disks are actually bigger than 90mm, the caps or actually 90mm and are installed on a smaller than 3" pipe, or what?

 

Thanks for any guidance you can provide.

 

Tom

 

 

Has anyone found or have a PID for a found example of a C&GS Triangulation Station pipe cap like shown in this illustration from Special Pub 11? I see lots of found BM caps from this time period (thanks kayakbird!) but I've been searching for photos of these with no luck.

 

IDZQK1x.jpg

0

Share this post


Link to post

For anyone who has found a US Coast & Geodetic Survey cap, did you happen to measure the diameter of the cap, or could you at least confirm if it is a larger diameter than a standard disk? I have never found one so I'm looking for the dimensions so I can model it in 3D. The old reports say they are made to fit a 3" pipe, but in other respects are exactly similar to the disk stations, which are about 90mm diameter. A 3" pipe has an OD of 3.5" (or 89mm), so a cap that was 90mm like the standard disk could would not work as a cap. I have measured a USGS BM Cap from the same era and it has an OD of about 3.9" (99 mm) and the pipe it was on was probably around 3.5" diameter, so is the USC&GS cap of a similar pattern?

 

The photos of the caps in the old bulletins look like they are the same diameter as the disk in the same picture, so I'm wondering if the flat top disks are actually bigger than 90mm, the caps or actually 90mm and are installed on a smaller than 3" pipe, or what?

 

Thanks for any guidance you can provide.

 

Tom

 

 

I took a road trip this weekend from St Paul to tiny Urdahl, MN to find an example of a U.S. Coast & Geodetic Survey Cap - benchmark U1 from 1904. This was the closest one to the twin cities (~160 miles) that I could find on my Survey Mark map. No entry for it on Geocaching.com, but the data sheet had some photos from 2010 so I figured it would still be there. Made the drive Saturday and found it easily.

 

YFXmUFn.jpg

 

hHfCftn.jpg

 

Took some measurements which confirm that it is smaller than the USGS BM cap I have found previously. This had a diameter of about 3.68" vs 3.9" for the USGS cap. This also had a domed top similar to the later USC&GS disks with a rounded edge where the USGS cap was flat topped with a nearly square edge.

 

It looks like it is mounted on a 3" ID pipe vs a 3.5" ID pipe for the USGS cap.

0

Share this post


Link to post

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
Sign in to follow this  
Followers 1