Hi,

Solid stitching is ACIS failing on the surfaces formed about/between 8 lines -- even if i try simplfy, even if i change gap from 0.00083" down to 0.5", even to 0.1". Even not requiring watertightness doesn't change it.

Definitely two strips of solid (running front to back along the x axis) have crazy twisting visible in the surface -- at least in a prior attempt.

I didn't yet try "sweeping", other than to select the pairs of lines that form each surface. On close-up zooming, the lines visually seem to make the surfaces mate up.

Just so you know, almost other (some 13 decks worth of plating) are OK, and the lines and waterlines and stations seem ok. Only in a very few so far start out intersecting, but the lose their intersection if cut -- even if the trim/cut is done ON the intersection.

Maybe the lines involved in forming very bad surfaces are "twisted" lines?


LOOONNNNNGER version.

Ignore the 4 longer, vertically-running lines. The stitching is my attempt to convert 6 surfaces into a solid (steel, mild steel)


Orientation:

-- left on the screen is forward on the x axis and model;

-- right on the screen is aft (back end)

-- right and away from you on the screen is starboard along the y axis

-- left and between you and the screen is port

The longest and vertically-running lines, if you want to know, define the watertight fore and aft boundaries of the compartment in question and those forward of and aft of the compartment in question (yes, it's a biggggg ship).

The outboard deck lines that are troublesome are the waterlines, which i exported from DELFTship as DXF 3D polylines. Being waterlines, on a non-parallel midbody vessel, they are curved.

The fore/aft deck lines i created in ViaCAD Pro, and they are not polylines, just straight lines parallel above/below each other. Creating a surface between the two forward and the two aft lines won't create a surface all the way out to and following the outer waterlines.

Converting the outboard lines' type to polyline within VCP straightens them and deforms them from their true shape (the hull was designed in DELFship, and i can't have any other apps modifying the curvature), so i leave them unchanged except for cutting/trimming.

At the after boundary, i was able to trim the line using the Intersect option, but when i tried to draw a line between the starboard line's aft point out to the portside's after boundary point, VCP doesn't show an "intersection" indicator. Interestingly, it was fine for the starboard side's forward line. Last night, the same problem, even though i used a cutting plane just to differentiate my approaches.

The problem happened at a farther forward location in the model (not included in the upload) and i resolved it by deleting the troubled lines reimporting their source, trimming, and skinning. But, that technique is not working today.

Since this is a symmetrical hull (as far as the decking goes) i so far am happy that by CGs information along the y axis is balanced (0).

Thanks for checking into it for me, Tim.

I am not sure how the cover became missing for the attachment. But, when i counted my surfaces i counted surfaces for the whole object, then for various sides, crossing the top, bottom, and one given side of each 4. I must've removed the surface prior to attaching.

I had this problem with i think only on other area in the hull. There probably was some serious curvature going on outward and upward.

I'll check my tolerances down from 0.0083" (the default?), but for the model attached, i couldn't not get a surface even at .05". IIRC, asking for it to skip enclosed volume or not to require watertightness, i couldn't get a final solid and hence not attach material/mass props.

As for Interpolated Spline, i thought i tried that, but at the zoom level i was in i immediately noticed the line shifting. So, i copied in a duplicate of the side-body waterline and the transom (aft end) waterline which was a single line (that i had to break). I then noticed that the polyline or interpolated line (or whatever it was) definitely was shifted and had a knuckle rather than a curve at 1 or 2 locations along the way.

I tried connecting native VCP lines between the fore and after parallels but then realized i created a solid of reduced volume and reduced surface area. For my hobby, it wouldn't matter unless i worry that some senior designer or naval architect scrutinized my model and went on an offensive, hehehee. At the scale i'm at, it's probably very small. But, i need to avoid accepting it if i want to claim i have accurate steel weight for the curves exported from DELFTship.

I'm starting to wonder though, about the misaligned intersections at some stations, whether the DXF export utilities are suspect. It's from maybe 2007 or 2006 or 2008, and i fear that maybe since i can't control the export version, it's likely to be very aged relative to say 2009 and 2010 import tools. Is that a valid concern?

Again, thanks for checking my curves--- uummm lines and giving feedback. I did comb the older 2D drafting posts to try to find a clue or in-app tool.

I will again revisit converting the lines to Interpolated Spline, and the ruled surface and the cover surface. Currently, i already use smooth/curved surface most of the time.

ZLC...