Freeship and Delftship

I use Carene 2008 as a starter for most of what I do. Problem is is that it isn't available anymore. For someone else to get it now you have to go to one of us old codgers who still keeps it around. BTW, you can get a double ender in carene by angling the transom an enormous amount. You also don't have to try and use metric with it if you don't want. If you plug in the numbers as if they were feet, then import into Freeship, you can scale it by .3048 in X,Y, and Z and it will end up in feet. First go into properties and set it to imperial, do the scale, then change the waterline to where you want it. 30 second switch.

 

Carene 2008 appears to be available for download at http://www.epoxy-resins.co.uk/Carene2013/carene.htm

 

Good to know... I haven't searched for the software for over a year, and when I did it wasn't available. Good to know it has re-surfaced.

 

heeled waterlines

I tried mirror and rotate on Freeship but couldn't get my waterlines to work. However by making 2 models at 25 and -25 exporting into parts, reimporting into a new file deleting one half of one and then displaying both layers in 1 side visable I got a heeled boat in perspective. Unfortunately the linesplan comes out with both hulls superimposed. But it does make a pretty picture.
I could print each part and cut each half of the plan .perhaps?

 

nice. A lot of work tho.

 

terrnz, I am thinking that if you mirror the hull first, then rotate it, would work. You would have turn off the show both side. What do mean about the water lines ?

 

This is a small half-stripped canoe design. I turned on the Shade Underwater in Project Settings. I turned off "Show Both Sides" and Mirrored the hull then Rotated 15 deg about longitudinal axis.

The waterlines, buttocks and stations all appear if they are turned on in the Visibility menu.

The displacement shown is the same (0.11T) for level and heeled conditions but the draft I set Project Settings in is the same when heeled. That's obviously wrong as the bottom is not a circular arc; I don't know how to make it correct, but I can select an arbitray greater draft in Project Settings - see the last image.

 

heeled waterlines

Frank and Terry, Thank you. I have gotten what I wanted.

The mistakes I have been making and trying to solve the challenges are giving me a much better insight into the programme.

 

on fairing

I totally agree with as few control points as possible and not chasing your tail so to speak. I went down that road and am surprised I did not have a mental breakdown!
I have been using the Gaussian mode as a guide. I cannot get the fairing tool to operate on Freeship.

Any hints?

One of my goals is to avoid compound curves as far as I can. Is this what they mean by developable?

 

Sounds like you're learning the ride the beast!

 

Fairing?

Why can't I get the curvature to work?

 

stability, GZ and Rm calcs.

Anyone shed any light?
after 10 deg they defy logic and experienced wisdom.

Examples:
1)take your hull and keel add 500Kg to the middle of the boat. run stability calcs. effectively internal ballast.
2)take same hull and put the extra 500kg in keel bulb. run stability calcs.
3)then take the keel with its extra 500kg and add a metre of draft to the fin. run calcs.

OK Cog changes but GZ remains the same! that is not how it works in the real world.

If I take the keel/bulb moment by sin(heel) and add it to the calculated I start to get a credible figure for RM.




I am not so interested in the heel below 10 deg, 15 to 30 is where it's at. More than that and ease , twist or reef.

so I am looking at the RM from the view hull buoyancy, keel factor and finally crew factor, fat boys on the rail!

Any observations, comments, etc. Is my approach flawed? any suggestions for a better model?

 

Cant be done in free versions as far as i know.

 

My model rotates beyond 90 deg no problem . . . but I haven't added ballast. You don't need ballast for heeling tests unless you are using cross-curves as far as I know.

 

When you change the vertical position of the CoG, without changing the displacement, value of GZ must change.
Caution: GZ = GM * sin (alpha) is only valid for heeling under 6 degrees