Carlson .tin

Wish I did, we have the same software, we have had to go back to several sites for additional topo for the engineering department. I just end up adding the new topo features to the drawing and re-running the tin.
If there is a way, I would really like to know also.

not that i know of, but here's what i do and once you've done it once or twice it's incredibly fast.

1. dump the new data and generate a new tin that includes a minimal amount of overlap into the area of the original tin (so, for instance, if you're gridding out a flat field, one or two rows of shots from the old surface).
2. in triangulation file utilities load the original tin, use the "merge tin" toggle, and choose the combine/overlap feature.
3. save the tin in whatever fashion you see fit (i always save tins by date name, should there be any question as to what occurred when)

i know this sounds cumbersome, but it really is not bad or time consuming. you get the added bonus of seeing how the new info merges into the original, and by "saving as" to a new, dated tin you can always revert to the original should there be any problems with the merge.

Thanks! The merge tin command is exactly what I was looking for.

Go to You tube and view the Carlson training videos. There are at least 2 on merging tins. Very well explained. The process is SO easy that most people thinh they must have done something wrong.