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Re: Full size drawings
By:Bram van der Sluys
Date: 7/23/1998, 10:40 pm
In Response To: Re: Full size drawings (npenney@erols.com)

> Yes they are sensitive, but it's an easy cure. Work opposing
> panels together, face to face. As in cut them, fair them, drill them.
> That's it. Piece of cake, done. No need for comparatively complex,
> bulky and difficult strongbacks. Like I said, I did the whole thing
> in one afternoon. Going in one afternoon from a stack of 4x8 sheets
> of plywood to complete cutouts, faired, drilled and sitting under
> cinderblocks being butt jointed. You can't get much faster or easier
> then that.

> You keep erasing the key though. BATTENS!!!

Unfortunately the cure is not so easy! Even if one makes both panel identical by stacking, if the joining line is not fair, as experienced recently by many on this bulletin board, then there will be a bulge or a hollow adjacent to the unfair portion of the line. There is no better way to get a fair line than a straight grained batten with as few ducks as possible. Three ducks will get a nice parabolic curve. A circlular curve can be reasonably forced with 4 or more ducks.

I have used a CAD program (Autocad) to produce lines for my skin on frame boats using circular curves. There are no visual clues the the curves aren't parabolic or produced by battens. Circular segments are extremely easy to work with but unfortunately lines for S&G panels are rarely circular. Most CAD programs' curve fitting routines leave something to be desired. I have been a draftsman all my working life and have used CAD for the past 13 years and I have lots of trouble with hull programs.

Bram

Messages In This Thread

I need graph paper
Matt Weist -- 7/21/1998, 4:06 pm
Re: I need graph paper
Mark Kanzler -- 7/21/1998, 6:36 pm
CAD for lofting
Karl Kulp -- 7/22/1998, 2:45 am
Re: CAD for lofting
Mark Kanzler -- 7/22/1998, 10:27 am
Re: CAD for lofting
Steve Austin -- 7/23/1998, 8:21 am
Re: CAD for lofting
Karl Kulp -- 7/24/1998, 6:33 pm
Re: CAD for lofting
Nick Schade -- 7/22/1998, 4:59 pm
Re: Full size drawings
NPenney -- 7/22/1998, 11:25 am
Re: Full size drawings
Mark Kanzler -- 7/22/1998, 11:38 am
Re: Full size drawings
NPenney -- 7/22/1998, 3:30 pm
Re: Full size drawings
Mark Kanzler -- 7/22/1998, 5:38 pm
Re: Full size drawings
npenney@erols.com -- 7/22/1998, 7:35 pm
Re: Full size drawings
Bram van der Sluys -- 7/23/1998, 10:40 pm
Re: Full size drawings
Mark Kanzler -- 7/24/1998, 5:46 pm
Re: Full size drawings
NPenney -- 7/24/1998, 7:14 am
Re: Full size drawings
Mark Carroll -- 7/23/1998, 5:40 pm
Re: Full size drawings
NPenney -- 7/24/1998, 6:40 am
Re: Full size drawings
Paul Lund -- 7/24/1998, 10:44 am
Re: I need graph paper
Mark Kanzler -- 7/21/1998, 4:52 pm
Re: I need graph paper
Mark Kanzler -- 7/21/1998, 4:31 pm
Re: I need graph paper
Mark Kanzler -- 7/21/1998, 4:37 pm