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Re: Tools: Printing Form outlines
By:Ross Sieber
Date: 2/8/2002, 3:13 pm
In Response To: Tools: Printing Form outlines (David J. Bonany)

: I've read a number of posts here of people who have mentioned that they print
: off the forms outlines on their computer. I'm curious how it is that
: people do this.

I don't know how much use this will be to you, but here's how I did it.
Your mileage may vary.
I use Linux instead of Windows. I couldn't find a CAD package I liked
that didn't cost more than I was willing to pay.

I input all the offsets into a spreadsheet, and adding scaling logic for
stretching/shrinking in X, Y and Z. I also put each form on a separate page
and added a chart, more as a sanity check than anything else. I found, as you
did, that you couldn't print anything useful.

I exported each form to a text file. I then used GNU plotutils to view them
all, separately and together, and add things like a cutout for a boxbeam,
reference lines and such, and ultimately print. The package has a splining
program that fits very nice curves through a set of data points. Sorting
the data into manageable units is entirely up to you, though. Order is also
important, and depends on the design of the boat, I found. Eg. do I spline
first, and then create the other half of the form, or vice versa? Spline
the hull and deck together, or seperately? This is not a magic bullet.

This package has no user interface to speak of. Everything is done
on the command line. Unless you are _very_ comfortable with Linux, this
is not for you. I probably wasted 50 sheets of paper getting the scaling
just so. If a point is slightly out of whack, and there will be a few, you
have to find it and fix it by hand - no point and click stuff.

I am quite happy with the results I got, so far, but I could probably have
done it faster by hand. On, the other hand, the second boat went much
faster, and the computer plots are probably better than I could have done by
hand. The spreadsheet also adds a great deal of quality control to the
scaling process. If your formulas are right, you can all but eliminate
human error from that part of the process.

I'll soon see how well I did, since I am just putting the forms for the first
boat on the strongback this weekend.

I am still playing with the other boat. The great thing is, I can tweak the
beam by 1/4" or whatever and it now costs virtually no time compared to
starting all over. The problem is, now I agonize over whether the beam should
be 22 or 22 1/4 or 22 3/8 ...

Was it worth it? I don't know. Plans are cheap.
Would I do it this way again? Yeah, probably.

Messages In This Thread

Tools: Printing Form outlines
David J. Bonany -- 2/8/2002, 10:24 am
Re: Tools: Printing Form outlines *Pic*
Eric -- 2/9/2002, 10:42 am
Re: Tools: Printing Form outlines
David Bonany -- 2/11/2002, 7:30 pm
Re: Tools: Printing Form outlines
John Monfoe -- 2/9/2002, 6:00 am
Re: Tools: Printing Form outlines
David Bonany -- 2/11/2002, 7:33 pm
Re: Tools: Printing Form outlines *Pic*
Walter -- 2/9/2002, 1:42 am
Re: Tools: Printing Form outlines
Ross Sieber -- 2/8/2002, 3:13 pm