Problem with Tables of Offsets

Ok I got the station curves all in they are pretty screwed up so gonna take a while to get them figured out
 

Attachments

  • Columbia-10.png
    Columbia-10.png
    363.4 KB · Views: 502
  • Columbia-11.png
    Columbia-11.png
    356.1 KB · Views: 404
The lines you show in #15 don't look like lines of a boat hull at all. And the indicated axes of coordinates (y,z) are not used in the common way.

May be you should take a bit more time to compare the drawings of the boat and the offset table to understand the relation better.

Edit: I didn't see TANSL's post #16. He is much more experienced than I am.
 
The pictures in post # 17 may well be the cross sections of a ship, although there are many shortcomings and probably not well located in space. But I think the OP is laying the correct groundwork to start a "fairing" job, which will certainly not be easy.
Mr Efficiency, no need to call Houston, a simple loftman will be a much better help.
 
The y,z coordinates of station 7 fed in a web tool to create cubic splines are showing a fair curve, not a curled one.
 

Attachments

  • spline_oRd.jpg
    spline_oRd.jpg
    139.9 KB · Views: 467
Ok I got the station curves all in they are pretty screwed up so gonna take a while to get them figured out

Yes those lines look a bit lumpy. I would be inclined to take any sketches/photographs of the hull and loft it from scratch. From there you can optimize the curves, run your stability & resistance checks on it, etc. until you achieve the performance you like.
 
yes I was just entering the curve tables from the offsets and those are the lines. I havent had time to check all the lines and the views above were taken in perspective some curves are fine while others very lumpy. plus I dont like the way they sit I want to do up the hull but since im so new at boats I wanted to try with the offsets table first

Now here was my Fletcher Hull using the Offsets I also did the SS United States with offsets. so normally I been doing good learning how to use them but this little boat seems FUBAR. I even tried delftship but that prog doesnt like me at all rofl. I figured this would be easy to do and I could make a boat out of it by spring to take grandkids radio control boating but right now doesnt look like it.
 

Attachments

  • Hull -02.jpg
    Hull -02.jpg
    142.7 KB · Views: 415
  • Hull -01.jpg
    Hull -01.jpg
    94.3 KB · Views: 344
  • Fletcher Hull.png
    Fletcher Hull.png
    68 KB · Views: 484
Here is what I did last night before generating the curve txt files.

I too the data from the original and reorganized the table to be more like I am used to seeing.

Now Solidworks needs the coordinates set up the Following way to generate the curves Properly:

Station Waterline Offset

I just need to put a space between each and stack them for each station and each station needs to be a separate txt file. to the right of the table I have them set up as individual stations and I just copy and paste the data into notepad.

I am just thinking the offset table data is way out of whack and when they laid down the hull and fixed any errors it didnt get adjusted in the offset table
 

Attachments

  • Columbia-12.png
    Columbia-12.png
    156.6 KB · Views: 460
It's easy to get lost in offset tables with a lot of entries. If only certain stations are affected I would isolate those and double-check the numbers for them. If they match the person defining the table probably made a mistake. You'll need to adjust the best you can.

I prefer to loft the lines in DelftShip or another good lofting tool, refine the splines (remove kinks & wrinkles), run all my calculations (hydrostatics, resistance) then export only the basic splines required to define your surface in SolidWorks (e.g. top profile, side profile, stations at 12" intervals). The exported splines will likely need to be scaled as well to match the units in SolidWorks (e.g. meters to mm).

Cheers,

Joseph
 
that would make life easier joseph however when I try to do anything in delftship my hull looks like a crumpled wad of paper. I will have to see if I can figure out how to get the offsets into the program and see if I can fudge in there. I am not holding my breath but like said I am still learning and for me its more for virtual modelling and radio control.

my radio control boats only round 6 ft long so any flaws really stand out
 
Ok I just finished tracing all the lines from the lines drawing sheet and saved them to DXF format after enlarging them to full scale. Now I will try to pull them into Delftship and see if I can figure out how to adjust everything to match without getting some crumpled paper again
 
Looking at your old table it will require conversion to the DelftShip format, which is basically listing your stations along X, and filling in points for Y & Z. Below is a sample input file. This example is for a simple canoe with a closed bow & stern (note 2nd column is at 0 (zero) to close them up.

If you can get your points into this format you're all set.

1

0 0 0
0 0 .17
0 0 .33
0 0 .5
0 0 .67
0 0 1.5

1 0 0
1 .0625 .17
1 .1146 .33
1 .1667 .5
1 .2188 .67
1 .3229 1.3021

2 0 0
2 .1563 .17
2 .2708 .33
2 .3646 .5
2 .4479 .67
2 .6563 1.1979

3 0 0
3 .2708 .17
3 .4479 .33
3 .5833 .5
3 .6875 .67
3 .8229 1.073

4 0 0
4 .4271 .17
4 .6458 .33
4 .7813 .5
4 .8854 .67
4 .9896 .9791

5 0 0
5 .6042 .17
5 .8229 .33
5 .9688 .5
5 1.0521 .67
5 1.125 .9063

6 0 0
6 .7708 .17
6 .9792 .33
6 1.0938 .5
6 1.15625 .67
6 1.1979 .8646

7 0 0
7 .90625 .17
7 1.0938 .33
7 1.1875 .5
7 1.2188 .67
7 1.2292 .8333

8 0 0
8 1 .17
8 1.1563 .33
8 1.2292 .5
8 1.2396 .67
8 1.2396 .8333

9 0 0
9 1.0313 .17
9 1.1771 .33
9 1.2396 .5
9 1.25 .67
9 1.25 .8333

10 0 0
10 1.0104 .17
10 1.1563 .33
10 1.2292 .5
10 1.2396 .67
10 1.2396 .8438

11 0 0
11 .9375 .17
11 1.0938 .33
11 1.1771 .5
11 1.1979 .67
11 1.2083 .8542

12 0 0
12 .7912 .17
12 .9688 .33
12 1.0625 .5
12 1.1042 .67
12 1.125 .8958

13 0 0
13 .5833 .17
13 .7813 .33
13 .875 .5
13 .9271 .67
13 .9583 .9583

14 0 0
14 .3542 .17
14 .5208 .33
14 .6146 .5
14 .6563 .67
14 .6979 1.0521

15 0 0
15 .1354 .17
15 .2292 .33
15 .3021 .5
15 .3334 .67
15 .3646 1.1875

16 0 0
16 0 .17
16 0 .33
16 0 .5
16 0 .67
16 0 1.3334

EOF
 

Attachments

I will try as I tried to pull the drawings in at full scale as png files and the program is giving me errors.

will see what I can come up with. what format does delftship use as for locations like i said solidworks uses stations, then waterlines, then offset data
 
here is what my txt file looks like with everything brought into it.

station 0 in the drawings is the transom and station 10 is in the bow

Station 0
792.00 135.500 62.000
792.00 120.000 64.000
792.00 108.000 65.000
792.00 96.000 65.000
792.00 84.000 59.000
792.00 72.000 41.000
792.00 60.000 63.000

Station 1/2
753.000 131.250 70.000
753.000 120.000 71.000
753.000 108.000 72.000
753.000 96.000 72.000
753.000 84.000 69.000
753.000 72.000 58.000
753.000 60.000 17.000

Station 1
714.000 129.750 77.000
714.000 120.000 78.000
714.000 108.000 79.000
714.000 96.000 77.000
714.000 84.000 76.000
714.000 72.000 69.000
714.000 60.000 47.000

Station 2
636.00 127.750 87.000
636.00 120.000 87.000
636.00 108.000 87.000
636.00 96.000 87.000
636.00 84.000 86.000
636.00 72.000 82.000
636.00 60.000 72.000
636.00 48.000 44.000
636.00 36.000 16.000

Station 3
558.00 127.000 93.000
558.00 120.000 93.000
558.00 108.000 93.000
558.00 96.000 93.000
558.00 84.000 92.000
558.00 72.000 89.000
558.00 60.000 82.000
558.00 48.000 61.000
558.00 36.000 34.000

Station 4
480.00 127.375 95.000
480.00 108.000 96.000
480.00 96.000 95.000
480.00 84.000 95.000
480.00 72.000 93.000
480.00 60.000 86.000
480.00 48.000 72.000
480.00 36.000 43.000

Station 5
402.00 128.750 96.000
402.00 96.000 96.000
402.00 84.000 95.000
402.00 72.000 93.000
402.00 60.000 87.000
402.00 48.000 73.000
402.00 36.000 44.000

Station 6
324.00 131.500 96.000
324.00 120.000 95.000
324.00 108.000 95.000
324.00 96.000 94.000
324.00 84.000 93.000
324.00 72.000 89.000
324.00 60.000 82.000
324.00 48.000 67.000
324.00 36.000 41.000

Station 7
246.00 135.500 94.000
246.00 132.000 93.000
246.00 120.000 91.000
246.00 108.000 89.000
246.00 96.000 86.000
246.00 84.000 82.000
246.00 72.000 77.000
246.00 60.000 63.000
246.00 48.000 55.000
246.00 36.000 33.000

Station 8
168.00 141.600 86.000
168.00 132.000 82.000
168.00 120.000 77.000
168.00 108.000 72.000
168.00 96.000 67.000
168.00 84.000 61.000
168.00 72.000 55.000
168.00 60.000 47.000
168.00 48.000 37.000
168.00 36.000 22.000

Station 9
90.000 149.900 64.000
90.000 132.000 52.000
90.000 120.000 46.000
90.000 108.000 41.000
90.000 96.000 37.000
90.000 84.000 32.000
90.000 72.000 28.000
90.000 60.000 23.000
90.000 48.000 17.000
90.000 36.000 9.000

Station 9 1/2
51.000 154.750 42.000
51.000 132.000 30.000
51.000 120.000 26.000
51.000 108.000 23.000
51.000 96.000 20.000
51.000 84.000 17.000
51.000 72.000 15.000
51.000 60.000 11.000
51.000 48.000 8.000

Station 10
12.000 159.750 9.000
12.000 132.000 5.000
 

Attachments

Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making any potentially dangerous or financial decision, always employ and consult appropriate professionals. Your circumstances or experience may be different.

  • Back
    Top