Braille benchmark disc?

[+Klemmer]

Ok, well, maybe it's not really braille, but that's the first thing that came to my mind when I saw DX2174 yesterday.

My best guess is E.B. RV MT and under the C317 is maybe LM

E.B. = the surveyor?

RV MT = Riveted Monument?

LM = supposed to have been BM?

 

Evidently, it was monumented sometime before 1949.

There are some side views on the GC webpage, and as you can see, it really is literally a pipe cap.

 

Anyone else seen any braille discs?

[foxtrot_xray]

Well, if they were blind, then I wouldn't comment about how they missed the center of the "X" with the hole.

 

If they weren't blind, then there's no excuse for that.

[+m&h]

We see your , so we figure you actually know that there's a good reason, not a mere excuse. Off-center punch marks are probably more plentiful than on-center punch marks. The point is surveyed, the pipe driven and capped, and then the precise point is measured again and found to be not in the exact center of the disk. They punch it where it is.

[foxtrot_xray]

We see your , so we figure you actually know that there's a good reason, not a mere excuse.

Yeah yeah, I'm aware of that. Was poking fun at the whole 'blind' thing. (In a lighthearted manner, honest.)

 

(And, honestly, to me it looks more like the "X" is off than the hole..)

[+GEO*Trailblazer 1]

I would re plumb the transit not move the marks center.

If it ain't centered it ain't centered.

[+Klemmer]

I don't think either the X or the center punch hole is centered, but it is what it is. Sure was fun, though. Also a nice long hike to get there.

[+GEO*Trailblazer 1]

Yep it really looks different thats for sure.

[+Okiebryan]

I would re plumb the transit not move the marks center.

If it ain't centered it ain't centered.

 

There is no possible way to set a pipe and cap monument and get it perfect. So as previously posted, you set the monument where the exact spot is, remeasure to the monument, and punch the exact spot without much regard to where it falls on the cap. Standard Operating Procedure.

[+GEO*Trailblazer 1]

OK,we did have a talk a way back on these little divets on benchmarks.

I think it was way................back there though.

 

Maybe I am to much of a perfectionist.

If it were me and my transit for recoreded observations,I would want it to set at the near the exact same point each time.

 

I thought that as what all them adjusting screws and points were for.

 

I also read somewhere if the instrument is not plumb and level measurements can be quite a bit off.

 

But with the modern day one's and the laser it is so much easier.

[+m&h]

GEO--

 

The issue in the above posts is not that your instruments can't get you to the same point twice, though that is indeed a matter of skill, delicacy and steadiness. It is rather that, once the point has been located, it is a very great physical challenge to drive a pipe into the ground and put a cap on it, such that the very center of the cap is exactly at the point you located. Same goes for disks in drill holes, or even in wet concrete.

[+Klemmer]

I didn't have any issue with the off-center center punch. I'm not a surveyor (I am an engineer), but I guess it was intuitive to me that you put the center punch where you need it to be.....

 

My "fascination" with this disc was all the OTHER punched holes. I suppose if one didn't have a set of letter / number punches, the monumenting surveyor did what he could. I'm assuming the C317 was added at a later date. It was just kinda unique!