Combination factor

TIB · Post by **TIB** » Sat Oct 19, 2013 8:36 am

After submitting a Parcel Map to City of XXXXX, they wanted me to provide calcs for the convergence angle and combination factor on the CCS 83 BoB ties, even though I took the data straight off their approved County wide control network per recorded ROS. It was 4 pages of longhand similar to a test that requires you to "show your work"
Is this normal? It's a first for me.
I must admit that it was sorta fun in a way since it's been 20 years or more doing it the hard way. (shows how boring my life is). But being required to calc took any fun out of it.
Naturally, I came up with different values than the published data. I sorta would like to check it before I give to City.The angle was same, but the combination factor was different. I verified the point scale factor by checking data with the NGS SPC utilities website.
?Can I also get a combination factor from NGS toolkit site or elsewhere from entering NAD N,E, elev, zone? If so, how?

Jim Frame · Post by **Jim Frame** » Sat Oct 19, 2013 10:59 am

Can I also get a combination factor from NGS toolkit site or elsewhere from entering NAD N,E, elev, zone?

Corpscon will do all that for you.

land butcher · Post by **land butcher** » Sat Oct 19, 2013 11:12 am

Is this required per City ordinance?

7702 · Post by **7702** » Tue Oct 22, 2013 6:33 am

FYI,

From the Corp's website:

CORPSCON Version 6.0

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KNOWN BUGS

- CORSPCON 6.0 provides an erroneous Combined Scale Factor

I haven't experimented with this to see if it's the elevation factor, the scale factor, or both that are incorrect.