What is the correct steps to get a Hard surface triangulated mesh converted to quads?
various combinations of ZRemesher with similar lumpy results, including Polygroup by normals 15, and Crease by PolyGroups.
There isn’t a single series of correct steps, unfortunately. There is only an array of tools that may be useful in different situations.
Make sure you have realistic expectations. No auto-retopo solution is going to make the same decisions a person could make about how best to cleanly draw edge creased topology at low poly levels. If you need that kind of topology, you should work from low poly to start, or manually retopologize your mesh by hand.
Zremesher has useful tools to help, though. If you are able to separate your mesh into different polygroups along edges, it can significantly improve the results you get by making use of the Keep Groups function. Detect Edges can help, but is limited.
If all you want to do is remesh into quads while still keeping your hard edges without concern for topology or polycount, simply dynameshing at high enough resolution will do that. This can be useful for 3d printing workflows that are just going to decimate everything anyway.
To get the best performance out of Zremesher at low poly for HS, you need to get creases involved though. In your situation, you appear to have a fairly low poly mesh with cleanly defined edges, so it should be possible for you to manually apply a crease to all those edges . I recommend a combination of grouping all the major planes into separate polygroups --polygroup by normals may be useful here–then creasing those polygroup borders with the functions in the Tool > Geometry> Crease menu, and using Zmodeler to touch up any gaps in the creasing.
You can activate dynamic subdivision periodically to preview the mesh non-destructively at higher level of subdivision to see how those creases are applying.
If you manage to get all those edges creased, ZRemesher can do a pretty great job if “Keep Creases” is active. If I’ve misread your screenshot, and all those edges actually are creased, you simply may not be giving Zremesher a high enough target polycount to work with.
As a tangential issue, make sure you are familiar with the shorcuts to quickly hide or mask polygons and polygroups. Working on meshes or creating polygroups efficiently is going to be difficult if those arent second nature to you.
I gave you a lot of general information here. If you have more specific questions, please let us know.
Good luck!
…that was my next test,
ZRemesher has been great for organic retopo! Thanks for the info, this will keep me busy.