Offset Tables And Lines Drawings

[DCockey]

The offsets for the waterlines and buttocks are typically used to draw the section at each station along with the any other offests at the particular station. The applicable waterline offsets are typically used in drawing the stem/keel/sternpost/transom.

[PerCorell]

Originally Posted by BASIL J WALL

Hi..
I just want some feedback from builders on the various continents...
How do you use offset tables and lines drawings from the designer, when you build a boat?
Do you set the lofting using the tables? Or do you measure from the lines and do your own lofting from them? What size of paper do you use to start this process?
I'm setting up a single sheet with lines and offsets on the same page which can be printed on 2' x 3' paper...it looks very busy and I personally, would rather have as large a drawing as possible on one page and have the offset tables on a separate sheet...

Thanks

Basil Wall

When you see a drawing of the one side of the hull there are sections, paralell lines all allon the drawing. These are the sections seen from the side. Each offcaurse look different seen from front of the hull, there they are ribs and often splines showing a row of cuts in the 3D model of the hull. They invented offset tables in the 17's century.
From side view, each rib looks the same, they are strait lines, just with different length -- later you can put this into a simple spreadsheet or even calculate it with a string as they originaly did. So id you point to a particular rib, forget alout all the others and look from front instead of the side you can read each rib and copy it from the xy measures describing a 2D spline.
If you make a catalog of each sections X.Y place describing a continous line, you have a table of offsets, see from the beginning you looked at paralell sections down a 3D boat hull model then what is good about it, computers newer was the caurse of foults they can't anything but do it right. People can, and esp. if they don't realy know, what they speak about.

Still with efficient design software and a CAD world that been surviving since it started the computer revolution, your internet, there are all sorts of math, ready made to just use, to unfold those spline surface, you get in a 3D program, by connecting all the sections, into a 3D form. Offcaurse there are a price but that is not bad measures, never that. But in real life, there are no realy good way to make that hull from one piect, so you make it from long panels, -- the same that you unfold from the 3D model offcaurse will deliver that, if you weld all panels along the boat together, on a jig made from other sections also taken from same 3D model ... to do it perfect, you make two hulls, one smaller offset true, within the other. So between the two, you have the volume, where some sort of frame system, make the ribs. I suggest 3dh there, ---- you allready have the 3d model so you can unfold the panels from the same model, that show you the advanced 3d volumes, where you display the ribs. --- in a 3d rendering after you had a small app. generate them as closed volumes, as without the real 3D model, you can't render them and check them by the image.

http://a3.sphotos.ak.fbcdn.net/hphot...25181126_n.jpg

[cthippo]

Originally Posted by DCockey

What do you put in the offset tables for the kayaks you've designed? Do you use software which automatically generates the offset table?

I design them in Freeship and use the output offsets to make the stations on the strongback.