Here's a silly question regarding plans

Draw your plane up in a CAD program, 3D CAD would be especially useful.

I agree CAD is very useful. It might take you 3 months of fooling around to
teach yourself well enough to make it a good tool but in my case I found the
time well spent. It's kind of nice, for example, to be able to drop a
different a different rudder pedal design into the drawing and discover that
the cable will make contact with the control stick at full deflection - before
- you actually build it.

It's also usefull to be able to make an acurate full size print of a part on
your own personal printer. Sometimes it's faster to draw up a simple part in
CAD, print it, and glue it on the material then it is to lay it out in the
conventional maner. This also avoids any distortions due to copy errors if
your plans have "full size" templates.

Your eventual distribution would be a lot cheaper,

IF - you can figure out a way to keep the files encrypted for use by the
purchaser only, and off the Internet........

I'll ditto the recommendation for the VP-1, VP-2, and Fly Baby plans.
I have all three. The FlyBaby plans are more than worth the money -
they contain the entire builder's manual as well. Very well done.
You might also look at the plans for the Piel Emeraude, available from
Sylvia Littner in Canada. That's a rather more complicated aircraft.

Your eventual distribution would be a lot cheaper,

IF - you can figure out a way to keep the files encrypted for use by the
purchaser only, and off the Internet........

Point. Intellectual-property law is pretty precise, and you'd be
protected by a strongly worded license agreement, assuming you're
willing to pay a lawyer to enforce it if required. There's also the
Law of Karma that all but guarantees that if you post for-sale plans
on the internet in violation of the license agreement, your airplane
will turn around and hurt you. It's amazing that people who plan to
spend $10,000 building an airplane would even consider screwing the
designer - to whom they will trust their life - out of a hundred bucks
or so. Scrounging for cheap materials and parts is one thing.
Inviting Bad Joss is quite another.

Corrie

Corrie wrote:
Point. Intellectual-property law is pretty precise, and you'd be
protected by a strongly worded license agreement, assuming you're
willing to pay a lawyer to enforce it if required. There's also the
Law of Karma that all but guarantees that if you post for-sale plans
on the internet in violation of the license agreement, your airplane
will turn around and hurt you. It's amazing that people who plan to
spend $10,000 building an airplane would even consider screwing the
designer - to whom they will trust their life - out of a hundred bucks
or so. Scrounging for cheap materials and parts is one thing.
Inviting Bad Joss is quite another.

Corrie

There is also the fact that no matter how good the drawings are, how
good your at reading them, or how detailed the instructions, there will
be something that just doesn't jive. Not to mention that one thing
you'll need to change. Having paid the designer his due will make
asking a question so much easier.

--
http://www.ernest.isa-geek.org/
"Ignorance is mankinds normal state,
alleviated by information and experience."
Veeduber

Ernest Christley wrote in message m...




Draw your plane up in a CAD program, 3D CAD would be especially useful.
Your eventual distribution would be a lot cheaper, and there is
nothing like being able to drop an additional line to get a measurement
between point that you find particularly convenient but the original
builder didn't/couldn't include because of space limitations on paper.

When the original builder is using CAD, measuring dimensions as you
indicate above is very useful. The builder is doing Computer Assisted
DESIGN, as opposed to so many who merely do computer asisted drafting.

But a cardinal rule for fabrication is to not rely on a dimension that
was determined by scaling from the drawing. You never know when the
draughtsman may have departed from the scale either when executing the
original or during revision. In particular, it is not uncommon for
revisions to be made by editing the dimentions without changing the
drawing per se.

Complete plans will have all the dimensions needed for fabrication
explicitly called out in the drawing package. If a necessary dimension
is missing then you should calculate it from the dimension that are
called out. People making plans should keep this in mind and try
to provide all the dimension needed for fabrication and to also call
them out on the drawing in a way that is useful for the person
doing the fabrication.

However, I learned standard practices for drawing and fabrication in
the nuclear industry. I appreciate that when not building reactor
vessels a more relaxed approach is appropriate and most of the plans
I have seen for sale are a good value for the price even if they
are less than complete by ASTM boiler and pressure vessel standards.

If you have to scale something for yourself off a drawing (or within
a cad model) then my advice is to be cautious and plan for a little
hand-fitting to make it right.

--

FF

Fred the Red Shirt wrote:

If you have to scale something for yourself off a drawing (or within
a cad model) then my advice is to be cautious and plan for a little
hand-fitting to make it right.


I was referring more to crosscheck measurements. You ever measure
something, maybe even two or three time, and just 'see' the measurement
you expect instead of what's actually there? With CAD, you can drop a
couple of extra measuments. Seeing a second measurement wrong is more
difficult. You have to be trying to screw up the third one. I like to
pull any important measurements from three points when I can. If
they're not all in agreement then I stop to figure out what's wrong.

--
http://www.ernest.isa-geek.org/
"Ignorance is mankinds normal state,
alleviated by information and experience."
Veeduber

Always better to measure twice and cut once.

Peter

Ernest Christley wrote in message m...
Fred the Red Shirt wrote:

If you have to scale something for yourself off a drawing (or within
a cad model) then my advice is to be cautious and plan for a little
hand-fitting to make it right.


I was referring more to crosscheck measurements. You ever measure
something, maybe even two or three time, and just 'see' the measurement
you expect instead of what's actually there? With CAD, you can drop a
couple of extra measuments. Seeing a second measurement wrong is more
difficult. You have to be trying to screw up the third one. I like to
pull any important measurements from three points when I can. If
they're not all in agreement then I stop to figure out what's wrong.

Again, ideally when fabricating you do not measure from the drawing and
apply the scale factor, and that is without regrad to whether you measure
with a ruler on a piece of paper or digitally within a software package.

You should use the dimensions called out on the drawing to calculate that
crosscheck measurement.

If you like, calculate it three ways and then average the answers.

;-)

--

FF