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Setting up a drawing in Civil 3D for Land Surveying

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(@bc-surveyor)
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I created a short(ish) video walkthrough of my process for setting up a C3D drawing for a surveying project. Mostly to go back to if/when I forget small details.

I thought I'd share in case there were any that aren't familiar with the transformation tab in C3D. As always any advice on how I can improve my methodology is always appreciated.

?ÿ

 
Posted : 22/01/2023 1:13 pm
(@wa-id-surveyor)
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That is an interesting workflow with lots of coordinate changes from grid to ground.?ÿ ?ÿMust be a BC thing????ÿ Once we set our project SF we work with ground coordinates exclusively, much less room for error.?ÿ We don't dare use any GIS parcel data in any area we work in.?ÿ It's typically garbage.?ÿ

The map cogo through the traverse editor is a new one for me. I've heard of it but never actually seen it in action.?ÿ No offense but it seems slow and painful.?ÿ We do all our COGO in separate drawings.?ÿ Each drawing get named per the recording info and saved out to a master database based on location.?ÿ Then we insert each survey/map into our primary drawing on a layer matching the recording info. Then we rotate around and fit the pieces together.

Why not just use a template with your settings already in it?

 
Posted : 23/01/2023 11:36 am
(@rover83)
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This is always a tough one for me, because I love OTF transformations and the ability to immediately relate files from different sources.

That being said....C3D is terrible at datum transformations, slightly less awful at unit designations, and the intersection of straight AutoCAD with C3D throws another wrench into the process.

But the bigger problem is that we can barely get surveyors to care about (much less understand how to) correctly set up DWGs. As soon as we go outside the survey/geomatics area of practice, all bets are off as to whether the various DWGs from additional disciplines will actually come together correctly. We have in-house engineers that we talk to regularly, and we still have trouble even conveying the importance of USFt vs iFt to our design colleagues.

And then guess who gets blamed for it and has to sort everything out?

So as much as it pains me to say it, I like my unitless, non-projected DWG setups.

It's going to get worse as more and more folks bring the ArcGIS Connector utility into the picture. Sure, the stuff you pull from AGOL might be getting transformed correctly (Web Mercator anyone?) but that's still dependent on how you set that DWG up in the first place. Then the DWG gets sent off to someone else and...did they set their base up right?

(I shouldn't complain too much, the screwups keep me employed...but no one really wants to pay me to solve problems after the fact. I'd rather do damage control up front if possible.)

 
Posted : 23/01/2023 12:28 pm
(@jitterboogie)
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@rover83?ÿ

VERIFIED AND FINALIZED LDPs for EVERYONE!!!!!

?ÿ

sorry...A guy has to dream a little bit......

 
Posted : 23/01/2023 12:35 pm
(@wa-id-surveyor)
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This is always a tough one for me, because I love OTF transformations and the ability to immediately relate files from different sources

Just set your SF and keep it turned off unless you need to turn it on for the geolocation tool or to import grid data from the variety of free data out there.?ÿ That's what we do and haven't had any issues at all.

 
Posted : 23/01/2023 12:55 pm
(@olemanriver)
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@rover83 That civil3d scares the heck out of me. I have done some adjustments lately and some quick auto linework in TBC. Export all the points and the linework saved as a dwg. Cad people gets data and start griping my linework is off my points are off every thing moved or shifted. Well I check everything on my end. All is good. International feet on his bringing my linework in but points are usft. To many units places for me to figure out as a rookie civil3d guy. Surface import has its own units points etc etc. why who thunk that up.?ÿ

Web Mercator oh now I could go on all night long with that one. Lol. Donƒ??t get my cartography side blasting that darn thing. ?ÿ

 
Posted : 23/01/2023 5:49 pm
(@bc-surveyor)
Posts: 226
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That is an interesting workflow with lots of coordinate changes from grid to ground.?ÿ ?ÿMust be a BC thing????ÿ Once we set our project SF we work with ground coordinates exclusively, much less room for error.?ÿ We don't dare use any GIS parcel data in any area we work in.?ÿ It's typically garbage.?ÿ

The map cogo through the traverse editor is a new one for me. I've heard of it but never actually seen it in action.?ÿ No offense but it seems slow and painful.?ÿ We do all our COGO in separate drawings.?ÿ Each drawing get named per the recording info and saved out to a master database based on location.?ÿ Then we insert each survey/map into our primary drawing on a layer matching the recording info. Then we rotate around and fit the pieces together.

Why not just use a template with your settings already in it?

?ÿ

There's a single coordinate change. Ground to grid that affects only the cogo points and imagery. It adds grid coordinates to your ground coodinates. If you import grid coordinates your transformation will be applied and move/scale/rotate your ground coodinates.

?ÿ

Yea the GIS linework is there only for a jumping off point to start your search. Its a situation of "the best we have at the time". It will be erased once we go out and tie some pins. In BC newer plans are georeferenced (+/- 0.05cm) and the linework dimensions are theoretically without error.

?ÿ

Im sure the traverse editor would be slow and painful for new users, like everything there is a learning curve. For me I can calc a plan as fast with that as other methods and having the GUI to go back to is fantastic.

?ÿ

I do use a template already setup, the point of this drawing is to walk through new users step by step how to set their settings.

?ÿ

 
Posted : 23/01/2023 7:14 pm
(@bc-surveyor)
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This is always a tough one for me, because I love OTF transformations and the ability to immediately relate files from different sources.

?ÿ

Im confused here, mind going into this a bit more?

?ÿ

That being said....C3D is terrible at datum transformations, slightly less awful at unit designations, and the intersection of straight AutoCAD with C3D throws another wrench into the process.

?ÿ

Is it? I havent had any issues, is there something in particular I should look out for?

?ÿ

But the bigger problem is that we can barely get surveyors to care about (much less understand how to) correctly set up DWGs.

?ÿ

Hence the video and creating a standardized procedure to setup your drawing.

?ÿ

As soon as we go outside the survey/geomatics area of practice, all bets are off as to whether the various DWGs from additional disciplines will actually come together correctly.

?ÿ

So the worry here would be one sector has a drawing in grid and you send them your drawing in your ground based system and they wont integrate? I could see that being an issue if a project didn't have an agreed upon ground system yet. I guess the remedy would be making a big header on the transformation parameters being used or before sending it out, turn off the transformation and scale everything into grid to create a grid only drawing, or only send them a scaled DXF and its easy to export the points in a grid CSV. We will very rarely send a DWG ever. It would always be a DXF and a CSV if needed.

?ÿ

We have in-house engineers that we talk to regularly, and we still have trouble even conveying the importance of USFt vs iFt to our design colleagues.

And then guess who gets blamed for it and has to sort everything out?

So as much as it pains me to say it, I like my unitless, non-projected DWG setups.

?ÿ

You mean you're just working in a ground system? You dont run into issues of needing it to be in grid? Im 100% unfamiliar with how things are done in the US but very curious and would love to learn more about it. Up here we definitely could not get away with not having our drawings in grid 90% of the time. Small one off site plans are fine and simple boundary stuff but any large projects or legal plans that requires geolocation would require it.

?ÿ

It's going to get worse as more and more folks bring the ArcGIS Connector utility into the picture. Sure, the stuff you pull from AGOL might be getting transformed correctly (Web Mercator anyone?) but that's still dependent on how you set that DWG up in the first place. Then the DWG gets sent off to someone else and...did they set their base up right?

(I shouldn't complain too much, the screwups keep me employed...but no one really wants to pay me to solve problems after the fact. I'd rather do damage control up front if possible.)

?ÿ

 
Posted : 23/01/2023 7:29 pm
(@bstrand)
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Surface import has its own units points etc etc. why who thunk that up.?ÿ

Yeah, I've yet to meet a surveyor that doesn't think survey points and figures are basically hot garbage.

I don't know if I'd trust TBC to export a file format that isn't their own.?ÿ I think I'd rather just export a properly coded point file and draft the map in Civil 3D to avoid potential mishaps.

 
Posted : 24/01/2023 8:24 pm
(@norman-oklahoma)
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Yeah, I've yet to meet a surveyor that doesn't think survey points and figures are basically hot garbage.

You have now. I'm perfectly comfortable with C3d and the surfaces created therein.?ÿ

 
Posted : 24/01/2023 9:50 pm
(@kjypls)
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I'm a new C3D user of two weeks now. I picked up a couple of new things.

I know you made it for yourself, but my constructive feedback is the pace was scorching fast (for me). I had to slow the playback speed down to keep track of your mouse.

Thanks for the video.

 
Posted : 25/01/2023 2:22 am
 jph
(@jph)
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Yeah, I've yet to meet a surveyor that doesn't think survey points and figures are basically hot garbage.

Maybe I'm not following you there.?ÿ But I've been using F2F creating linework and breaklines, since the 90's

Started in Softdesk/LDD, moved on to Carlson

 
Posted : 25/01/2023 5:07 am
(@bstrand)
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@jph

Oh the auto linework is fine.?ÿ I'm talking specifically about the double sets of points with cogo and survey points and survey figures.

 
Posted : 25/01/2023 5:58 am
(@wa-id-surveyor)
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Yeah, I've yet to meet a surveyor that doesn't think survey points and figures are basically hot garbage.

You have now. I'm perfectly comfortable with C3d and the surfaces created therein.?ÿ

Make that two! The points are great, no issues at all and the survey figures are good, if setup and tied properly but can get a little messy on occasion.

@BStrand - no idea what you're talking about with double set of points.?ÿ 10years in Civil3d and have not had any double sets of point issues??ÿ What specifically is happening on your end?

?ÿ

 
Posted : 25/01/2023 6:13 am
(@rover83)
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I'm a fan of C3D as well for drafting and topo. It's great for designing subdivision/plat lots as well, once you set up the automated tools correctly.

I've never had double points either, and I've been using C3D more or less consistently since 2009.

Even though I prefer TBC for linework processing, C3D works just great when it is set up right. The only problem I have had with survey figures is getting linetypes to display correctly. It's been a while since I have run C3D linework processing, so maybe that has been fixed. In any case I just ran a LISP routine to copy the survey figures to 2D polylines and place the figures on a hide layer so they could still be used for surface creation.

?ÿ

To address @bc-surveyor 's question about datums and transformations...this is my main beef with C3D. It presents itself as a program with geodetic functionality, but does not actually deliver.

We often work near the boundary between the Washington State north and south zones. If I have two drawing files, one set to WA-North and the other to WA-South, and both contain the exact same polygon representing the exact same parcel boundary (geodetically speaking), they will not line up if I Xref one into the other. It just dumps on drawing file on top of the other. Hence my "no OTF transformations" comment.

Datums are likely more of an issue here in the USA because we are currently running in NAD83 rather than ITRF/WGS84. But we often receive shapefiles from subs or third parties that are in the latter system and need to get them into C3D.

However, even with an NAD83 datum and projection set in the C3D drawing file, and with the correct WGS84 PRJ file set for the shapefile, C3D will not transform from ITRF/WGS84 to NAD83 during import. Instead, it just projects them as if the ITRF positions were NAD83 (null transformation). Around here the shift is about 1.5-2m, which can make for a bad day down the road, because it sometimes looks like it's "right".

In order for those datums to be correctly transformed, one has to create an entirely new set of datums, transformations, and projections tied to them. It works - Iƒ??ve tested it - but it shouldnƒ??t be necessary at all and would be a gigantic pain to have to roll out custom CS definitions and tell everyone to ignore the standard ones.

So all that is to say that what C3D says it can do, it does not really do.

Perhaps this is a minor issue at the moment, but as I mentioned upthread, there are a LOT more users nowadays pulling data into their projects from outside sources with no understanding of what is going on under the hood. It will likely become even more critical in the coming years once NATRF2022 is "released".

?ÿ

That being said, I still love C3D for drafting.

 
Posted : 25/01/2023 6:48 am
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