This sounds like a great way of hayduking someone whose done you
dirty. Just slip a key into their door, turn it, take it out and walk
away. Cause them hours and dollars worth of hassle.
Wolf K. wrote:
"Or cars: Just a few weeks ago, my niece and nephew bought an new
The niece tried to open the car with the keys to their older car
make, same key-series), and the new car promptly shut down.
Took a tow, and a couple hours work by a technician to persuade the
onboard computer to let the car run again. I guess the shut-down is a
"security feature." Stoopid IMO. "
Nice work. When is the Plymouth model going to be made?
How does one pick up how to to CAD? I learned mechanical drawing in
JHS and college back in the early 80s. I never did it profesionally.
I've been trying to learn CAD for like ten, twelve years now by myself
with no luck. I've tried Deltacad and Cad 3-D. I just can't get it.
Never heard of 'em, which should tell you something. ;-) I've found no
two CAD programs to have the same quirks. IE, there is _no_ standard to
their operations. EG, some draw a circle with the clicked point as the
centre, some draw it tangent to that point. Etc. -- What I'd like is a
CAD operation that allows me to draw a line or curve, and then drag and
rotate it to where I want it.... haven't found one that does this, but
it must be out there.
Try starting with free-hand, dimensioned sketch. Then draw one line at a
time. A proper CAD program allows you to specify a line by end point in
terms of x, y co-ordinates, and length. So think graph paper, and things
will start to become clear. I hope. ;-) It worked for me.
Not that CAD is that much easier than paper and pencil, in fact it's
more of a hassle than it's worth for the kind of small projects most
people want to draw -- you know the kind for which a sketch plan is
usually enough, anyhow. Such as an 8x12 garden shed, for example. You
really don't need drawings accurate to 1/16" for that. ;-)
The fairly steep learning curve for any kind of computer assisted
creativity program (whether it's CAD, or music composition, or image
processing) is the reason that few amateurs use them. That's why track
planning software is not as widely used as its makers would like: just
how precisely do you need to plan a 4x8 layout? Or a 18"x10' shelf
layout? Sketches on 1/4" squared paper are more than good enough.
CAD is worth the learning effort for professionals, because it
eliminates the professional's bane: the effect of a design change, or
error in dimensioning, which will require the redrafting of at least
that drawing, and usually many others. But the actual design of the
drawing, ie, the design of the object being drafted, is as much a
creative task whether you use hand drafting or CAD, or 2D or 3D.
Creativity, the envisioning of possibilities and the translation of
these into visuals that others can understand, is not made any easier by
CAD. If you have 5 thumbs on each hand, CAD just makes it easier to make
nice, neat drawings, is all. Once the design is more less settled, then
CAD proves its worth: it's easy to create variations, and easy to make
That's my two cents worth.
On Sun, 13 Jan 2008 12:07:13 -0500, Wolf K. wrote:
But for planning to use something other than one manufacturer's sectional
track, it's a marvelous tool and worth the time - as well as being useful
for all sorts of drawing projects (at least Cadrail is).
Sectional track? Wozzat??
(Just kidding.) ;-)
I've designed a lot of layouts, at least five designed for others were
built. I never assumed the use of sectional track, just used the radii
that the commissioning friend said he wanted to use. Since sectional
track comes in certain radii (eg, 18", 22", etc for Atlas), that's all
you really need to know. It's easy to estimate the number of sections of
track needed, and if some won't fit as sold, just cut 'em up. One should
never be limited by the manufacturer's notion of useful lengths of track.
For turnouts, I had a template cut out of card, showing location of
points, frog, and clearance points at each end (where the tracks are far
enough apart for trains to pass each other safely.) Actually, I used
templates for everything, including curves. I allowed enough clearance
for easements. I never tried to squeeze in an extra few inches of
track, as that guaranteed construction problems.
Have you tried CadStd? From what I remember (I'm short on time here so
I'm not going to research it), it allows you to choose your circle
drawing method from the menu. You can also sorta drag and drop your
shapes once done, by moving them. Select the shape, activate the move
command, select a point on the shape, move to where you want that shape,
Nice simple program, but it does have its quirks. It looks at the GUI
differently than most other programs.
Marching to the beat of a different drum is great... unless you're in
The Plymouth is proceeding slowly as there are other, higher priority
projects ahead of it (mostly honey do's). I need a little more work on
the brass casting (the bottom part) to get it ready to be quoted.
Luckily here in Rhode Island there is still some remnants of the jewelry
industry that used to be a major part of the economy. So there are
several investment casting houses that excel at small, detailed castings.
As far as learning CAD, I would resist any temptation to learn 2-D
first, especially if this is a career move. There is no future in it. In
fact, there is no future in 2-D drawings in any form, digital or paper.
As an engineering communication tool, they are headed for the shredder.
All required information for any purpose can be imbedded in solid model
files including dimensions, dimensional and geometric tolerances,
material and finish and anything else required. The advantage that a
machine operator has when (s)he can view a solid model on the computer
screen and rotate it all directions first before proceeding cannot be
Before going to the computer, look at some simple shapes and think about
how they could be (and are) formed. A solid cylinder is often formed on
a lathe by turning it on its axis. For a hollow cylinder, move a circle
along a line perpendicular to its plane, as in forming a hole by
plunging a drill or end mill. Form a donut (torus) by rotating a circle
about an axis in its plane. For a free form piece of wire or tubing,
move a circle along a 3D spline. And so on.
These are the same ways the computer will form solids. Frequently you
draw a shape on a plane or existing planar surface and then move it
through space in some controlled way. It is either adding or
subtracting "material" as it goes, depending on the need. Real and
computer parts are combinations of these simpler moves.
For learning the mechanics of using a particular program, I found it
most helpful to do every tutorial I could find. Also, see if you can
find a users group to join, especially a local one in which you can meet
face to face with people who have either already learned it or are going
through the same thing you are.
Good luck. It will be worth the effort.
While I won't disagree that 2-D drawings are going out as far as
finished drawings are concerned, I do disagree that learning 2-D drawing
is a waste of time. All a 2-D drawing is is a straight-on view of one
side of a 3-D image. Sometimes you lose important details when you try
to look at multiple sides at once.
I find them easier to dimension and read dimensions off them, but this
is only for my own use. If I had to do just a 3-D drawing, I'm pretty
sure I wouldn't use CAD.
Disclaimer: CAD and mechanical drawing is just a hobby to me.
Marching to the beat of a different drum is great... unless you're in
Oh, please. Right now, you sound like one of those old fogeys who
complains about all those young whippersnappers. You could have started
this rant with, "Back in *my* day..." It would have fit right in.
Have you ever done CAD or hand drafting? Do you have idea of the skill
involved in creating a CAD drawing? It certainly doesn't appear so.
I was in the very last mechanical hand drafting class in my college
(Wentworth Inst. of Tech., Boston, MA) in the Fall of 1993. I consider hand
drafting to be one of my hobbies as I enjoy putting pencil to paper. I
still do a lot of my initial sketching for any drawing by hand. But there's
no way in hell that I would ever consider doing it for a living with
deadlines and such hanging over me. One little mistake in drafting, and you
either burn a lot of eraser or start over. One little mistake in CAD, and I
can just lasso the whole part and move it over a fraction or whatever I need
I have used AutoCAD r11, 12, 13, & 14 (it's been a while), and I also
use 3rdPlanIt for layout design. It's a different skill to be sure, but CAD
needs just as much skill as drafting to get it right. Sure, there's less
artistic skill in CAD...but this is mechanical drafting, not art class.
Aren't these drawings in MR, etc. also famous for being frequently
Paul A. Cutler III
Weather Or No Go New Haven
I have used Acad 13, but prefer Microstation. I currently use
M-station 95 on my old 486 computer. It's more than enough for my needs.
One thing I have noticed since CAD has become so readily available:
people drafting who know just enough about it to put their idea on
paper, but not enough to do a proper drawing. My pet peeves are overly
complex drawings and improper dimensioning. If a design is complex
enough to do more than one drawing DO it. Also, keep the fershluggener
dimensions out of the way and to a minimum, the term "typ" seems to
confuse some people. I have seen extension lines obscure details too
many times. Back in the paper and t-square days my instructors were
fanatics about dimensioning.
Dan, U.S. Air Force, retired
When I was a carpenter (up until this last August) I would love to call up
the architects or more commonly Designer (this means Art Major with CAD
program and pretensions of Frank Lloyd Wright) to get them to explain their
math or to get useful dimensions. The first answer would be that we must
have screwed up our framing and they would come out to the site and show us
how we screwed up and then we would get out our plans and show them that
are measurements matched the plans. The next target was always the computer
must have made a mistake. I often wondered of these guys would benefit in
lesson on the computer acronym GIGO
And the irony is that a good carpenter can build a sound structure with
no more than properly dimensioned _sketch plan_. That's what our friend
did when he added an enclosed porch to our house. I gave him a ground
plan, and front view, and cross section. He modified my roof truss
design, and suggested an 8ft width rather than the 6ft I'd sketched,
because he doesn't liking cutting plywood any more than he has to. Did a
great job - the porch is now a sun room, too.
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