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Replies:
53
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Last Post:
Sep 10, 2003 5:24 AM
Last Post By: old-cadaver
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Posts:
204
Registered:
11/25/03
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Dimensioning an isometric drawing
Posted:
Sep 1, 2003 5:06 PM
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How can I dimension an isometric drawing? When I try to dimension an object, the dimension lines do not follow the object correctly. They dimension in a 2d view. It doesn't matter if I switch on the drafting setting to use isometric views. Or even change the to the top, left or right. It still dimensions strangely.
Is there another setting I'm missing? Please let me know. I'm using ACAD 2004.
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Re: Dimensioning an isometric drawing
Posted:
Sep 1, 2003 6:18 PM
in response to: kb
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DIMALIGNED?
How
can I dimension an isometric drawing? When I try to dimension an object, the
dimension lines do not follow the object correctly. They dimension in a 2d
view. It doesn't matter if I switch on the drafting setting to use isometric
views. Or even change the to the top, left or right. It still dimensions
strangely.
Is there another setting I'm missing? Please let me know. I'm using ACAD
2004.
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Re: Dimensioning an isometric drawing
Posted:
Sep 2, 2003 2:44 AM
in response to: kb
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dimedit > select Oblique > select object >
enter angle to set extension lines for dimension.
How
can I dimension an isometric drawing? When I try to dimension an object, the
dimension lines do not follow the object correctly. They dimension in a 2d
view. It doesn't matter if I switch on the drafting setting to use isometric
views. Or even change the to the top, left or right. It still dimensions
strangely.
Is there another setting I'm missing? Please let me know. I'm using ACAD
2004.
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Re: Dimensioning an isometric drawing
Posted:
Sep 2, 2003 5:58 AM
in response to: kb
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I have noticed that some people have a
misunderstanding of what an isometric drawing is. Some people think that
an isometric view is an accurate view of an object, viewed from a certain skewed
angle. If that is your understanding of an isometric drawing, then
attempting to dimension it using isometric options views will not work.
Could that be the problem?
How
can I dimension an isometric drawing? When I try to dimension an object, the
dimension lines do not follow the object correctly. They dimension in a 2d
view. It doesn't matter if I switch on the drafting setting to use isometric
views. Or even change the to the top, left or right. It still dimensions
strangely.
Is there another setting I'm missing? Please let me know. I'm using ACAD
2004.
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Re:
Posted:
Sep 2, 2003 6:11 AM
in response to: Richardson, Randy
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I'll expand on what I wrote for the benefit of
anyone who is unclear as to what I'm saying. Isometric drawing is a 2D
method of drawing an object in such a way that a viewer of the drawing gets a
rough idea what the shape of the object is. It was never meant to be an
accurate depiction, only an approximation. The methods used to draw the
line lengths are meant for ease of use for a drafter using drafting tools,
rather than for creating an accurate picture. Perhaps in the age of 3D
drafting it is no longer necessary to use the conventions of isometric
drawing. Perhaps it would be helpful to compare it to the
various methods used to represent a map of the whole planet on a flat
sheet. There is no way to accurately depict the entire planet on a flat
sheet without showing distortions. The difference from one method to
another is deciding which features to distort. The world-famous Merceator
(sp?) Projection shows the north pole as being the same length as the
equator. We know that that is a distortion, but it is true to the rules
set forth to create a Merceator Projection. In like manner, an isometric
drawing uses various agreed-upon rules to make a somewhat distorted image.
It is based more on ease of drawing than absolute accuracy. Computers perhaps render such concerns moot, but I
still have vivid memories of drawing everything by hand. When AutoCAD was
created, they obviously wanted to mimic most of the conventions that draftsmen
have always used, whether they made sense for computers or not. I only
wish they had paid more attention to how hidden lines should be represented in
various situations. That is still done incorrectly, to this day, but now
it's become so common due to CAD ubiquity that what was once frowned upon is now
accepted. -Randy Richardson
I have noticed that some people have a
misunderstanding of what an isometric drawing is. Some people think that
an isometric view is an accurate view of an object, viewed from a certain
skewed angle. If that is your understanding of an isometric drawing,
then attempting to dimension it using isometric options views will not
work. Could that be the problem?
How
can I dimension an isometric drawing? When I try to dimension an object, the
dimension lines do not follow the object correctly. They dimension in a 2d
view. It doesn't matter if I switch on the drafting setting to use isometric
views. Or even change the to the top, left or right. It still dimensions
strangely.
Is there another setting I'm missing? Please let me know. I'm using ACAD
2004.
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Posts:
5,183
Registered:
12/12/03
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Re:
Posted:
Sep 2, 2003 6:35 AM
in response to: Richardson, Randy
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I only wish they had paid more attention to how hidden lines should be represented in various situations. That is still done incorrectly, to this day,<< ?? Isn't that the drafter's responsibility?? |
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Re:
Posted:
Sep 2, 2003 6:47 AM
in response to: old-cadaver
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You're right. The entire drawing is the
drafter's responsibility. To their credit, Autodesk has made it easy for
drafters to fulfill their responsibility correctly in most respects, so perhaps
I should not complain about one of the few areas where they have utterly failed
to do so. I think that very few drafters in this day and age are aware
that it's not always desirable to start a hidden line with a segment instead of
a gap. Perhaps this can be blamed on the fact that we there are fewer
drafting classes and more CAD classes these days. To me it is frustrating,
and I'm powerless to affect things much. Fortunately, I don't lose any
sleep over this.
>I only wish they had paid more attention to how hidden
lines should be represented in various situations. That is still done
incorrectly, to this day,<<
?? Isn't that the drafter's responsibility??
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Posts:
583
Registered:
12/10/03
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Re:
Posted:
Sep 2, 2003 9:58 AM
in response to: Richardson, Randy
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I think that very few drafters in this day and age are >aware that it's not always desirable to start a hidden >line with a segment instead of a gap. Explain please. I can not remember EVER starting a hidden line with a gap, and the classes I took did not mention any reason to do so. Jerry |
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Re:
Posted:
Sep 2, 2003 10:30 AM
in response to: lsaapedd
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If an object line ends at the same point as a
hidden line, and if they depart from that same point in opposite directions, the
intent is clearer and it looks cleaner if the hidden line starts with a
gap. This is how I was trained when I used a pencil instead of a
mouse. Since AutoCAD cannot have a hidden line that starts with a gap, I
compensate by breaking the hidden line a little distance from the
end. If your classes were CAD classes rather than drafting classes, I'm
not surprised that they never mentioned this. If they were drafting
classes, then they should have (IMHO) mentioned it. -Randy
I think that very few drafters in this day and age are
aware that it's not always desirable to start a hidden >line with a
segment instead of a gap.
Explain please. I can not remember EVER starting a hidden line with a gap,
and the classes I took did not mention any reason to do
so.
Jerry
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Re:
Posted:
Sep 2, 2003 10:41 AM
in response to: Richardson, Randy
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Amen on the "CAD Operator" class vs. Drafting. CAD
training is long on commands on short on technique.
If an object line ends at the same point as a
hidden line, and if they depart from that same point in opposite directions,
the intent is clearer and it looks cleaner if the hidden line starts with a
gap. This is how I was trained when I used a pencil instead of a
mouse. Since AutoCAD cannot have a hidden line that starts with a gap, I
compensate by breaking the hidden line a little distance from the
end. If your classes were CAD classes rather than drafting classes, I'm
not surprised that they never mentioned this. If they were drafting
classes, then they should have (IMHO) mentioned it.
-Randy
I think that very few drafters in this day and age are
aware that it's not always desirable to start a hidden >line with a
segment instead of a gap.
Explain please. I can not remember EVER starting a hidden line with a
gap, and the classes I took did not mention any reason to do
so.
Jerry
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Re:
Posted:
Sep 2, 2003 10:45 AM
in response to: jonesr
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And sometimes short on
both. |
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Re:
Posted:
Sep 2, 2003 11:28 AM
in response to: Richardson, Randy
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ISO 128 (valid in Denmark as DS/ISO 128) specifies that: 1) When a dashed line is in direct continuation of a solid line, it should start with a gap. 2) In any other cases, the dashed line shall start with a segment. (my translation from Danish) In the drafting training book I've consulted it is noted that the above criteria cannot always be fulfilled when using CAD. Peter "Randy Richardson" skrev i en meddelelse news:1436A68684D605CE182701738D40C2D5@in.WebX.maYIadrTaRb... If an object line ends at the same point as a hidden line, and if they depart from that same point in opposite directions, the intent is clearer and it looks cleaner if the hidden line starts with a gap. This is how I was trained when I used a pencil instead of a mouse. Since AutoCAD cannot have a hidden line that starts with a gap, I compensate by breaking the hidden line a little distance from the end. If your classes were CAD classes rather than drafting classes, I'm not surprised that they never mentioned this. If they were drafting classes, then they should have (IMHO) mentioned it. |
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Re:
Posted:
Sep 2, 2003 12:26 PM
in response to: Blazejewicz, Pe...
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Thanks for backing me up, Peter. All I had to go on was 25-to-30-year-old memories. "Peter Blazejewicz" wrote in message news:B7B59E8812579B53E3B2E970A8C29992@in.WebX.maYIadrTaRb... ISO 128 (valid in Denmark as DS/ISO 128) specifies that:
1) When a dashed line is in direct continuation of a solid line, it should
start with a gap.
2) In any other cases, the dashed line shall start with a segment.
(my translation from Danish)
In the drafting training book I've consulted it is noted that the above
criteria cannot always be fulfilled when using CAD.
Peter |
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Re:
Posted:
Sep 2, 2003 4:56 PM
in response to: Richardson, Randy
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Vocational Drafting in 1964.
If an object line ends at the same point as a
hidden line, and if they depart from that same point in opposite directions,
the intent is clearer and it looks cleaner if the hidden line starts with a
gap. This is how I was trained when I used a pencil instead of a
mouse. Since AutoCAD cannot have a hidden line that starts with a gap, I
compensate by breaking the hidden line a little distance from the
end. If your classes were CAD classes rather than drafting classes, I'm
not surprised that they never mentioned this. If they were drafting
classes, then they should have (IMHO) mentioned it.
-Randy
I think that very few drafters in this day and age are
aware that it's not always desirable to start a hidden >line with a
segment instead of a gap.
Explain please. I can not remember EVER starting a hidden line with a
gap, and the classes I took did not mention any reason to do
so.
Jerry
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Re:
Posted:
Sep 2, 2003 11:27 AM
in response to: Richardson, Randy
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Randy can you explain the difference between an
"orthographic" veiw and an "Isometric" veiw? or are they the
same?
You're right. The entire drawing is the
drafter's responsibility. To their credit, Autodesk has made it easy for
drafters to fulfill their responsibility correctly in most respects, so
perhaps I should not complain about one of the few areas where they have
utterly failed to do so. I think that very few drafters in this day and
age are aware that it's not always desirable to start a hidden line with a
segment instead of a gap. Perhaps this can be blamed on the fact that we
there are fewer drafting classes and more CAD classes these days. To me
it is frustrating, and I'm powerless to affect things much. Fortunately,
I don't lose any sleep over this.
>I only wish they had paid more attention to how hidden
lines should be represented in various situations. That is still done
incorrectly, to this day,<<
?? Isn't that the drafter's
responsibility??
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Re:
Posted:
Sep 2, 2003 11:37 AM
in response to: Swartz, Dustin
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From m-w.com Isometric: 1 : of, relating to, or characterized by
equality of measure; especially : relating to or being a
crystallographic system characterized by three equal axes at right
angles
Orthographic Projection: 1 : projection of a single view of an object (as a
view of the front) onto a drawing surface in which the lines of projection are
perpendicular to the drawing surface
2 : the representation of
related views of an object as if they were all in the same plane and projected
by orthographic projection
Randy can you explain the difference between an
"orthographic" veiw and an "Isometric" veiw? or are they the
same?
You're right. The entire drawing is the
drafter's responsibility. To their credit, Autodesk has made it easy
for drafters to fulfill their responsibility correctly in most respects, so
perhaps I should not complain about one of the few areas where they have
utterly failed to do so. I think that very few drafters in this day
and age are aware that it's not always desirable to start a hidden line with
a segment instead of a gap. Perhaps this can be blamed on the fact
that we there are fewer drafting classes and more CAD classes these
days. To me it is frustrating, and I'm powerless to affect things
much. Fortunately, I don't lose any sleep over this.
>I only wish they had paid more attention to how
hidden lines should be represented in various situations. That is still
done incorrectly, to this day,<<
?? Isn't that the drafter's
responsibility??
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Re:
Posted:
Sep 2, 2003 12:46 PM
in response to: Swartz, Dustin
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An orthographic view is an exact picture of an object (neglecting
perspective). It was also explained to me that you're viewing an object
from an infinite distance. I think it was explained that way to justify the
fact that the lines that move away from the eye do not appear to converge
(or diverge depending on how you look at it) as you would expect with a
perspective drawing. Based on the theory that parallel lines converge at an
infinite distance, so this is how an object would look if the parallel lines
that go toward (or away from) you converge at your eye. It's probably
easier just to say "neglecting perspective" and let it go at that.
An isometric drawing is not an orthographic view, although an orthographic
view can be drawn that will approximate the apperance of isometric drawing.
An isometric drawing does approximate the appearance of a solid object if
you look at it from a skewed viewpoint. However, the lines that go along
the x, y, and z axes are drawn exactly to scale. If it is a 3" long line,
it is drawn 3" long. It is not shortened to account for the fact that the
line is sloping away from you in one direction or another. If it sounds
archaic, I would agree, but by definition that's what isometric drawing is.
-Randy
"Dustin Swartz" wrote in message
news:B0FE0A9D5E285B125BB9D6B0D40B51F0@in.WebX.maYIadrTaRb...
Randy can you explain the difference between an "orthographic" veiw and an
"Isometric" veiw? or are they the same?
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Posts:
5,183
Registered:
12/12/03
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Re:
Posted:
Sep 3, 2003 3:59 AM
in response to: Richardson, Randy
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Autodesk has made it easy for drafters to fulfill their responsibility correctly in most respects, so perhaps I should not complain about one of the few areas where they have utterly failed to do so.<< How is that AutoDESK's failure?? If a drafter fails to properly present his drawing, that's the drafter's failure, right? Or was it Kohinoor's fault when we were drawing by hand? |
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Re:
Posted:
Sep 3, 2003 6:20 AM
in response to: old-cadaver
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Old Cadaver, Now that this discussion is evolving from a
discussion of facts to the realm of opinion, I'm a little less enthusiastic
about it. But I'll give it another shot. Now I agreed with you that if the drawing is not
presented properly it is completely the drafter's responsibility. Maybe
that thought got lost among the rest of my verbosity. If the tools are
inadequate, he has to compensate in whatever way he needs to to make it
right. Suppose that Autodesk had never created the
"fillet" command? Well OK, there are still ways of drawing fillets without
it. What if they had not created 9 different ways to draw an arc?
Well fine, you one really need one way. You could still defend Autodesk to
the death about the ability to make fillets and arcs in AutoCAD. However,
Autodesk has always been anxious to make things as easy as they can for users,
and that is why they dominate the CAD market. All I did was bring up one
area where things could have been better. If you're offended by my saying
"utterly failed to" (that probably is a little inflammatory, albeit completely
accurate) then I most profusely apologize. This issue for me isn't whether the drafter can
present the drawing right, but how easy is it to do it? I do think that
the real blame for bad drafting techniques is in the state of drafting training
today. For some reason, it seems that CAD training has become a substitute
for drafting training. If more people knew how to do it right, there would
be more pressure on Autodesk to make it easy for the drafters to do it
right. Now I really don't want to get into a ping-pong
match over opinions. I know that you are a loyal, true-blue defender of
Autodesk. AutoCAD has transformed my life for the better, and I will also
defend it, but I tend to question things that I think can be done
better. Then again, I could well be completely wrong.
That's the thing about opinions. Randy Richardson
>Autodesk has made it easy for drafters to fulfill their
responsibility correctly in most respects, so perhaps I should not complain
about one of the few areas where they have utterly failed to do so.<<
How is that AutoDESK's failure?? If a drafter fails to properly present his
drawing, that's the drafter's failure, right? Or was it Kohinoor's fault when
we were drawing by hand?
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Posts:
5,183
Registered:
12/12/03
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Re:
Posted:
Sep 3, 2003 7:19 AM
in response to: Richardson, Randy
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If you're offended by my saying "utterly failed to" (that probably is a little inflammatory, albeit completely accurate) then I most profusely apologize.<< I'm not offended by the statement, I just disagree that it is accurate. The "FROM POINT" of a line is completely up to the drafter. If the drafter fails to start the line from the proper point, how has AutoDESK failed? pressure on Autodesk to make it easy for the drafters to do it right>I know that you are a loyal, true-blue defender of Autodesk. << There are several things for which I will take AutoDESK to task, things in which they have "utterly failed". This just isn't one of them. Then again, I could well be completely wrong. That's the thing about opinions.<< me too |
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Re:
Posted:
Sep 2, 2003 12:56 PM
in response to: Richardson, Randy
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Randy I have to take exception to you saying that
isometrics were "never meant to be an accurate depiction, only an
approximation". I think that is misleading, at best, if not outright
incorrect. Whether a drawing is prepared as an isometric projection
or isometric drawing, the image shown is accurate and not an
approximation. If you are saying that the lengths of lines that are not on
the isometric planes are not an accurate size then I can agree.
Isometric projection does result in a reduction in
the size of the features of an object, but the object is not approximated.
Perhaps I have misunderstood your use of the term approximation as it relates to
iso's. If drawing an isometric drawing, then the lines
falling on the iso planes are true length. Whether an object is an orthographic projection or
an isometric projection, the details of the object are shown accurately. I
don't think the example of a map of the world is a valid example of isometric
limitations. My 2 cents. Kent Elrod "Randy Richardson" <> wrote in message
I'll expand on what I wrote for the benefit of
anyone who is unclear as to what I'm saying. Isometric drawing is a 2D
method of drawing an object in such a way that a viewer of the drawing gets a
rough idea what the shape of the object is. It was never meant to be an
accurate depiction, only an approximation. The methods used to draw the
line lengths are meant for ease of use for a drafter using drafting tools,
rather than for creating an accurate picture. Perhaps in the age of 3D
drafting it is no longer necessary to use the conventions of isometric
drawing.
Perhaps it would be helpful to compare it to the
various methods used to represent a map of the whole planet on a flat
sheet. There is no way to accurately depict the entire planet on a flat
sheet without showing distortions. The difference from one method to
another is deciding which features to distort. The world-famous
Merceator (sp?) Projection shows the north pole as being the same length as
the equator. We know that that is a distortion, but it is true to the
rules set forth to create a Merceator Projection. In like manner, an
isometric drawing uses various agreed-upon rules to make a somewhat distorted
image. It is based more on ease of drawing than absolute
accuracy.
Computers perhaps render such concerns moot, but
I still have vivid memories of drawing everything by hand. When AutoCAD
was created, they obviously wanted to mimic most of the conventions that
draftsmen have always used, whether they made sense for computers or
not. I only wish they had paid more attention to how hidden lines should
be represented in various situations. That is still done incorrectly, to
this day, but now it's become so common due to CAD ubiquity that what was once
frowned upon is now accepted.
-Randy Richardson
I have noticed that some people have a
misunderstanding of what an isometric drawing is. Some people think
that an isometric view is an accurate view of an object, viewed from a
certain skewed angle. If that is your understanding of an isometric
drawing, then attempting to dimension it using isometric options views will
not work. Could that be the problem?
How
can I dimension an isometric drawing? When I try to dimension an object,
the dimension lines do not follow the object correctly. They dimension in
a 2d view. It doesn't matter if I switch on the drafting setting to use
isometric views. Or even change the to the top, left or right. It still
dimensions strangely.
Is there another setting I'm missing? Please let me know. I'm using
ACAD 2004.
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Re:
Posted:
Sep 2, 2003 1:14 PM
in response to: Elrod, Kent
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It all depends on how you look at it, Kent, whether you call it an "accurate
depiction" or not. Since a 3" line that would normally be shortened because
it's angled away from you is drawn fully 3" long, and since you would never
see it that way in reality, I say it's not an accurate depiction. On the
other hand, since a 3" line is drawn 3" long, from that viewpoint you can
say it is an accurate depiction.
Also, you used the term "isometric projection," which I term wouldn't use
because you're not projecting anything as you would with an orthographic
view, even a 3rd angle view. I do admit that the "help" files for AutoCAD
call a 3D view from a skewed angle an "isometric view," but that is a recent
innovation, and does not jive with the traditional 2D isometric drawing
techniques which are, incidentally, also fully supported by AutoCAD.
-RR
"Kent Elrod" wrote in message
news:4C856263B6BBD1CD258CD8D9B34EEEBC@in.WebX.maYIadrTaRb...
Randy
I have to take exception to you saying that isometrics were "never meant to
be an accurate depiction, only an approximation". I think that is
misleading, at best, if not outright incorrect. Whether a drawing is
prepared as an isometric projection or isometric drawing, the image shown is
accurate and not an approximation. If you are saying that the lengths of
lines that are not on the isometric planes are not an accurate size then I
can agree.
Isometric projection does result in a reduction in the size of the features
of an object, but the object is not approximated. Perhaps I have
misunderstood your use of the term approximation as it relates to iso's.
If drawing an isometric drawing, then the lines falling on the iso planes
are true length.
Whether an object is an orthographic projection or an isometric projection,
the details of the object are shown accurately. I don't think the example
of a map of the world is a valid example of isometric limitations.
My 2 cents.
Kent Elrod
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Re:
Posted:
Sep 2, 2003 2:21 PM
in response to: Richardson, Randy
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Randy
There are various types of Axonmetric Projections, with Isometrics being one
of them. Isometric projection is the method of rotating the object being
represented, then projecting parallel visual rays to an imaginary plane
perpendicular to the rays, from a line of sight at infinity. Orthographic
projection is done in the same manner with the notable exception that the
object is turned so that only one plane is parallel to the projection plane.
That is what I mean by isometric projection
Isometrics can also be made with a method known as isometric drawing when
the drawing is prepared with an ordinary scale so that all isometric planes
are measured true length. Lines not falling parallel to the isometric
planes are shown but not are not to scale.
Many lines shown in orthographic projection are not to scale either,
requiring the use of auxillary views to show them true size, while
distorting other features of the object.
You mention "3rd angle view", I don't know if you mean 3rd angle projection
or not. I find no reference to "3rd angle view" in any books I have. 3rd
angle projection refers to the layout of the views for orthographic
projection.
Not sure what you mean when you say 3D views don't jive with traditional 2D
isometric drawing. 3D views set in a SE, SW, NE, NW view are exact
isometric projections, as described above.
Yes autocad supports 2d isometric drawings, but I wouldn't say fully
supports. After all, adding a simple dimension to an isometric requires a
lot of additional work to accomplish. With the power of 3D, even in vanilla
autocad, I prefer to create a 3D model of the object and project isometrics
from any vantage point I choose.
Sincerely,
Kent Elrod
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Re:
Posted:
Sep 2, 2003 2:36 PM
in response to: Elrod, Kent
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Kent, It looks like we're disagreeing over definitions. Isometric drawing means one thing to you, and something else for me. I'm just using the definitions that were given to me when I was being trained as a draftsman. And, according to those techniques, I would say that AutoCAD fully supports isometric drawing. Adding a simple dimension to an AutoCAD isometric drawing is as easy as any other dimension if it's a true isometric drawing rather than a projection. One thing that I trust we would not disagree over is how to make an accurate drawing projection, whether it's called isometric or not. I'm pretty sure I understand what you're saying. I'm less convinced that you understand what I'm saying--not through any fault of yours, of course. But it appears to boil down to a disagreement over definitions, and that is something I prefer not to debate over. Because what you are calling "isometric" I would call a 3rd angle orthographic projection, although I'm less sure of that definition. It's possible that permitting CAD developers to redefine the word "isometric" has eroded the original definition. That's OK, languages are always evolving. There's no way to control definition drift, although it will often cause confusion (as illustrated here). -Randy "Kent Elrod" wrote in message news:5E6227D9433903CAFFEEC612890AC3A2@in.WebX.maYIadrTaRb... Randy
There are various types of Axonmetric Projections, with Isometrics being one of them. Isometric projection is the method of rotating the object being
represented, then projecting parallel visual rays to an imaginary plane
perpendicular to the rays, from a line of sight at infinity. Orthographic
projection is done in the same manner with the notable exception that the
object is turned so that only one plane is parallel to the projection plane. That is what I mean by isometric projection
Isometrics can also be made with a method known as isometric drawing when
the drawing is prepared with an ordinary scale so that all isometric planes are measured true length. Lines not falling parallel to the isometric
planes are shown but not are not to scale.
Many lines shown in orthographic projection are not to scale either,
requiring the use of auxillary views to show them true size, while
distorting other features of the object.
You mention "3rd angle view", I don't know if you mean 3rd angle projection or not. I find no reference to "3rd angle view" in any books I have. 3rd
angle projection refers to the layout of the views for orthographic
projection.
Not sure what you mean when you say 3D views don't jive with traditional 2D isometric drawing. 3D views set in a SE, SW, NE, NW view are exact
isometric projections, as described above.
Yes autocad supports 2d isometric drawings, but I wouldn't say fully
supports. After all, adding a simple dimension to an isometric requires a lot of additional work to accomplish. With the power of 3D, even in vanilla autocad, I prefer to create a 3D model of the object and project isometrics from any vantage point I choose.
Sincerely,
Kent Elrod
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Re:
Posted:
Sep 2, 2003 2:36 PM
in response to: Richardson, Randy
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Why would you want to draw in isometric, when it is so much easier and faster to draw a 3d model and SOLPROF it from the appropriate view angle. Obviously, you dimension the model, not the projection. "Randy Richardson" wrote in message news:7D60A4794927F12F8C95348C0708C2CA@in.WebX.maYIadrTaRb... Kent,
It looks like we're disagreeing over definitions. Isometric drawing means
one thing to you, and something else for me. I'm just using the definitions that were given to me when I was being trained as a draftsman. And,
according to those techniques, I would say that AutoCAD fully supports
isometric drawing. Adding a simple dimension to an AutoCAD isometric
drawing is as easy as any other dimension if it's a true isometric drawing
rather than a projection. One thing that I trust we would not disagree over is how to make an accurate drawing projection, whether it's called isometric or not. I'm pretty sure I understand what you're saying. I'm less convinced that you understand what I'm saying--not through any fault of yours, of course. But it appears to boil down to a disagreement over definitions, and that is something I prefer not to debate over. Because what you are calling "isometric" I would call a 3rd angle orthographic projection, although I'm less sure of that definition. It's possible that permitting CAD developers to redefine the word "isometric" has eroded the original definition. That's OK, languages are always evolving. There's no way to control definition drift, although it will often cause confusion (as illustrated here). -Randy "Kent Elrod" wrote in message news:5E6227D9433903CAFFEEC612890AC3A2@in.WebX.maYIadrTaRb... Randy
There are various types of Axonmetric Projections, with Isometrics being one of them. Isometric projection is the method of rotating the object being represented, then projecting parallel visual rays to an imaginary plane
perpendicular to the rays, from a line of sight at infinity. Orthographic projection is done in the same manner with the notable exception that the object is turned so that only one plane is parallel to the projection plane. That is what I mean by isometric projection
Isometrics can also be made with a method known as isometric drawing when the drawing is prepared with an ordinary scale so that all isometric planes are measured true length. Lines not falling parallel to the isometric
planes are shown but not are not to scale.
Many lines shown in orthographic projection are not to scale either,
requiring the use of auxillary views to show them true size, while
distorting other features of the object.
You mention "3rd angle view", I don't know if you mean 3rd angle projection or not. I find no reference to "3rd angle view" in any books I have. 3rd angle projection refers to the layout of the views for orthographic
projection.
Not sure what you mean when you say 3D views don't jive with traditional 2D isometric drawing. 3D views set in a SE, SW, NE, NW view are exact
isometric projections, as described above.
Yes autocad supports 2d isometric drawings, but I wouldn't say fully
supports. After all, adding a simple dimension to an isometric requires a lot of additional work to accomplish. With the power of 3D, even in vanilla autocad, I prefer to create a 3D model of the object and project isometrics from any vantage point I choose.
Sincerely,
Kent Elrod
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Re:
Posted:
Sep 3, 2003 5:58 AM
in response to: kev
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Kev, I agree. I am not an advocate of drawing in isometric. It made a lot more sense back before computers were used to do drafting. I am only advocating the idea that the original definition of isometric drawing is not consistent with the way the word is often being used nowadays. Comparing AutoCAD's isometric-drawing capabilities with other areas of the "help" files makes it clear that Autodesk is using both the old definition and the new definition in different situations, perhaps without realizing it. -Randy "kev" wrote in message news:402FFC3E7C12704743C0491CF4109A74@in.WebX.maYIadrTaRb... Why would you want to draw in isometric, when it is so much easier and
faster to draw a 3d model and SOLPROF it from the appropriate view angle.
Obviously, you dimension the model, not the projection. |
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5,183
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Re:
Posted:
Sep 3, 2003 6:42 AM
in response to: Richardson, Randy
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ACAD uses the phrase "Isometric View" to describe a 3D view from unit vector points (1,1,1 or 1,-1,1 etc.). The 2D plot resulting from these unit vector views is a 30-60 "Isometric" (not projected).
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Re:
Posted:
Sep 3, 2003 6:46 AM
in response to: old-cadaver
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They sure do. ACAD
uses the phrase "Isometric View" to describe a 3D view from unit vector points
(1,1,1 or 1,-1,1 etc.). The 2D plot resulting from these unit vector views is
a 30-60 "Isometric" (not projected). |
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Re:
Posted:
Sep 3, 2003 6:20 AM
in response to: kev
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Why would you want to draw in isometric, when it is so much easier and faster to draw a 3d model and SOLPROF it from the appropriate view angle. Obviously, you dimension the model, not the projection.<< It's even easier and faster to skip the SOLPROF and annotate the actual model, not a 2D representation of the model. |
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Re:
Posted:
Sep 10, 2003 4:40 AM
in response to: old-cadaver
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Isn't that what I
said? SOLPROF is just to bring in
the hidden lines, and take the triangles off the curved
surfaces.
>Why would you want to draw in isometric, when it is so
much easier and faster to draw a 3d model and SOLPROF it from the
appropriate view angle. Obviously, you dimension the model, not the
projection.<<
It's even easier and faster to skip the SOLPROF and annotate the actual
model, not a 2D representation of the model.
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Posts:
5,183
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12/12/03
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Re:
Posted:
Sep 10, 2003 5:24 AM
in response to: kev
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SOLPROF creates a separate 2D representation (with hidden lines) of the 3D model.
Skip that step, and annotate the model. (related commands: OBSCUREDLTYPE, OBSCUREDCOLOR, DISPSILH, FACETRES, UCS)
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Re:
Posted:
Sep 3, 2003 5:37 AM
in response to: Richardson, Randy
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I was taught two years ago that Isometric was a specific type of Axonometric
drawing using 30 and 60 degree angles to define the projection. Was I
mislead?
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Re:
Posted:
Sep 3, 2003 6:30 AM
in response to: Kirkham, Jon
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Jon, That's sort of correct as far as it goes, but doesn't go far enough. I gotta confess, though, this word "axonometric" is a new one for me. Isometric drawing is distinguished by the fact that the lines along the x, y, and z axes are drawn their true length, even though you wouldn't see it that way in reality, since the lines are angles away from you. Although this results in a somewhat distorted picture, it gives a good idea as to the shape of the object. At least that's the traditional definition of "Isometric," and the definition that Autodesk obviously used when they created the 2D Isometric drawing tools. I'm surprised that no one is backing me up on this, but maybe most of the old-timers left drafting when AutoCAD got big. The few that are left don't care about this or maybe they think I'm wrong too, and all of that is fine too, because in the grand scheme of things, it's really no big deal now that we have all the 3D tools. -Randy "Jon Kirkham" wrote in message news:E4441DD460279020054F7EE86472C969@in.WebX.maYIadrTaRb... I was taught two years ago that Isometric was a specific type of Axonometric drawing using 30 and 60 degree angles to define the projection. Was I
mislead?
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Re:
Posted:
Sep 3, 2003 6:48 AM
in response to: Richardson, Randy
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Randy,
my understanding was that axonometric denotes a drawing that is measurable
along x,y, and z axes. Isometric is more specific, defining the x axis as 30
degrees above horizontal, and the y axis as 30 degrees off vertical (or
perpendicular to the x axis). All lines that are parallel to the x,y, and z
axis are drawn to scale.
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Re:
Posted:
Sep 3, 2003 7:13 AM
in response to: Richardson, Randy
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Randy I am an old timer and am referencing one of the old drafting books when talking about isometrics. As I said there are two basic ways to draw isometrics, one is a projection which shows the object with the axes foreshortened the same way one would view the object in real life. The other is an isometric drawing which allows you to draw the isometric lines true size. I started learning drafting back in 1968 and attended college in the early 70's taking many advanced drafting classes. So I consider my self an old timer as well. Obviously all work was done on the drafting board. I am not sure why you say there is distortion in an isometric view. Unless you mean because the lines don't appear to move to a vanishing point as in a perspective view. But, an isometric is defined as being viewed from infinity which is why the lines stay parallel to one another. BTW, I am referening the book "Technical Drawing" which has been around since 1933. My copies are the 1967 edition and the 2000 edition. Kent Elrod "Randy Richardson" wrote in message news:7D016F12332FB8E37AD121285051B031@in.WebX.maYIadrTaRb... Jon,
That's sort of correct as far as it goes, but doesn't go far enough. I
gotta confess, though, this word "axonometric" is a new one for me.
Isometric drawing is distinguished by the fact that the lines along the x,
y, and z axes are drawn their true length, even though you wouldn't see it
that way in reality, since the lines are angles away from you. Although
this results in a somewhat distorted picture, it gives a good idea as to the shape of the object.
At least that's the traditional definition of "Isometric," and the
definition that Autodesk obviously used when they created the 2D Isometric
drawing tools.
I'm surprised that no one is backing me up on this, but maybe most of the
old-timers left drafting when AutoCAD got big. The few that are left don't care about this or maybe they think I'm wrong too, and all of that is fine
too, because in the grand scheme of things, it's really no big deal now that we have all the 3D tools. -Randy "Jon Kirkham" wrote in message news:E4441DD460279020054F7EE86472C969@in.WebX.maYIadrTaRb... I was taught two years ago that Isometric was a specific type of Axonometric drawing using 30 and 60 degree angles to define the projection. Was I
mislead?
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Re:
Posted:
Sep 3, 2003 7:35 AM
in response to: Elrod, Kent
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Kent, I'm sorry, I missed when you said there are two basic ways to draw isometrics. I guess I'm saying roughly the same thing when I say that there are two definitions of isometric drawing. So I'm going to take this as an agreement. My assertion was that drawing "with the axes foreshortened the same way one would view the object in real life" was a recent innovation (as far as the definition of "isometric" goes), but if it's in your old book that way, I'll accept that I was wrong about that. Since you agree that there are two ways to do it, then you'll have to agree that the drawings made by the two different methods will not be identical to each other. When I said there were distortions, I meant that if you don't draw "with the axes foreshortened the same way one would view the object in real life" then the picture is distorted. I'm discounting the effects of perspective as you did. And that's why I said that AutoCAD fully supports 2D isometric drawing, because it supports the method I learned. Sounds like it'll take a couple of years for me to catch up with your "old timer"liness. -Randy "Kent Elrod" wrote in message news:09EC7906D5BD7E670E43BC82D214A2DB@in.WebX.maYIadrTaRb... Randy
I am an old timer and am referencing one of the old drafting books when
talking about isometrics.
As I said there are two basic ways to draw isometrics, one is a projection
which shows the object with the axes foreshortened the same way one would
view the object in real life. The other is an isometric drawing which
allows you to draw the isometric lines true size.
I started learning drafting back in 1968 and attended college in the early
70's taking many advanced drafting classes. So I consider my self an old
timer as well. Obviously all work was done on the drafting board.
I am not sure why you say there is distortion in an isometric view. Unless you mean because the lines don't appear to move to a vanishing point as in a perspective view. But, an isometric is defined as being viewed from infinity which is why the lines stay parallel to one another. BTW, I am referening the book "Technical Drawing" which has been around since 1933. My copies are the 1967 edition and the 2000 edition. Kent Elrod "Randy Richardson" wrote in message news:7D016F12332FB8E37AD121285051B031@in.WebX.maYIadrTaRb... Jon,
That's sort of correct as far as it goes, but doesn't go far enough. I
gotta confess, though, this word "axonometric" is a new one for me.
Isometric drawing is distinguished by the fact that the lines along the x, y, and z axes are drawn their true length, even though you wouldn't see it that way in reality, since the lines are angles away from you. Although
this results in a somewhat distorted picture, it gives a good idea as to the shape of the object.
At least that's the traditional definition of "Isometric," and the
definition that Autodesk obviously used when they created the 2D Isometric drawing tools.
I'm surprised that no one is backing me up on this, but maybe most of the old-timers left drafting when AutoCAD got big. The few that are left don't care about this or maybe they think I'm wrong too, and all of that is fine too, because in the grand scheme of things, it's really no big deal now that we have all the 3D tools. -Randy "Jon Kirkham" wrote in message news:E4441DD460279020054F7EE86472C969@in.WebX.maYIadrTaRb... I was taught two years ago that Isometric was a specific type of Axonometric drawing using 30 and 60 degree angles to define the projection. Was I
mislead?
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Re:
Posted:
Sep 3, 2003 9:06 AM
in response to: Elrod, Kent
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FWIW, I posted this a couple of years ago from my edition: From my "Technical Drawing"*, ch 16, sec 4: "The Isometric scale. A correct isometric projection may be drawn with the use of a special scale, prepared on a srtip of cardboard, Fig 16.4. All distances in the isometric scale are sq rt(2/3) times true size, or approximately 80 percent of the true size. ..." [fig 16.4 shows a standard scale at 45 degrees projected down to the isometric scale at 30 degrees.] Ch 16, sec 5: "Isometric Drawing. When a drawing is prepeared with an isometric scale, or otherwise as the object is actually projected on a plane of projections, it is an isometric prjection, as illustrated in Fig. 16.5 (a). When it is prepared with an ordinary scale, it is an isometric drawing, illustrated at (b). The isometric drawing, (b), is about 25 percent larger than the isometric projection (a), but the pictorial value is obviously the same in both. Since the isometric projection is foreshortened and an isometric drawing is full-scale size, it is usually adbantageous to amek an isometric drawing rather than an isometric projection. The drawing is much easier to execute and, for all practial purposes, is just as satisfactory as the isometric projection." * Technical Drawing Eighth Edition by: Frederick E. Giesecke Alva Mitchell Henry Cecil Spencer Ivan Leroy Hill John Thomas Dygdon (c) 1986, Macmillan Publishing Company ISBN 0-02-342600-4 (hardcover edition) ISBN 0-02-946220-7 (international edition) Enjoy, Stef "Kent Elrod" wrote on 03 Sep 2003: [snip] BTW, I am referening the book "Technical Drawing" which has been
around since 1933. My copies are the 1967 edition and the 2000
edition. -- mailto: yodersj@earthlink.net_remove_ http://www.flatmtn.com/ || CAD / Computers Hardcore LT users: Doing what they say can't be done. |
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Re:
Posted:
Sep 3, 2003 9:33 AM
in response to: Yoder, S.
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Thank you, Stef. I appreciate it. Randy "S. Yoder" wrote in message news:Xns93EB85B6D391Dyodersj@64.124.46.110... FWIW, I posted this a couple of years ago from my edition: From my "Technical Drawing"*, ch 16, sec 4: "The Isometric scale. A correct isometric projection may be drawn with the use of a special scale, prepared on a srtip of cardboard, Fig 16.4. All distances in the isometric scale are sq rt(2/3) times true size, or approximately 80 percent of the true size. ..." [fig 16.4 shows a standard scale at 45 degrees projected down to the isometric scale at 30 degrees.] Ch 16, sec 5: "Isometric Drawing. When a drawing is prepeared with an isometric scale, or otherwise as the object is actually projected on a plane of projections, it is an isometric prjection, as illustrated in Fig. 16.5 (a). When it is prepared with an ordinary scale, it is an isometric drawing, illustrated at (b). The isometric drawing, (b), is about 25 percent larger than the isometric projection (a), but the pictorial value is obviously the same in both. Since the isometric projection is foreshortened and an isometric drawing is full-scale size, it is usually adbantageous to amek an isometric drawing rather than an isometric projection. The drawing is much easier to execute and, for all practial purposes, is just as satisfactory as the isometric projection." * Technical Drawing Eighth Edition by: Frederick E. Giesecke Alva Mitchell Henry Cecil Spencer Ivan Leroy Hill John Thomas Dygdon (c) 1986, Macmillan Publishing Company ISBN 0-02-342600-4 (hardcover edition) ISBN 0-02-946220-7 (international edition) Enjoy, Stef "Kent Elrod" wrote on 03 Sep 2003: [snip] BTW, I am referening the book "Technical Drawing" which has been
around since 1933. My copies are the 1967 edition and the 2000
edition. -- mailto: yodersj@earthlink.net_remove_ http://www.flatmtn.com/ || CAD / Computers Hardcore LT users: Doing what they say can't be done. |
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Re:
Posted:
Sep 3, 2003 6:55 AM
in response to: Kirkham, Jon
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Jon, that is somewhat misleading. Because of the limitation of the tools available to draw isometrics on the board (namely the few available triangles) isometric drawings were traditionally drawn with the three axonometric axes at 90 degrees, 30 degrees and 150 degrees. The definition of an isometric is " one is which all angles between the axonometric axes are equal". So as long as the three axes are 120 degrees from one another it is an isometric. We have come to think that there should always be a vertical axes in an isometric, but again, that is due to the ease of drawing on a board. I started on the board so I know a little about that. Kent "Jon Kirkham" wrote in message news:E4441DD460279020054F7EE86472C969@in.WebX.maYIadrTaRb... I was taught two years ago that Isometric was a specific type of Axonometric drawing using 30 and 60 degree angles to define the projection. Was I
mislead?
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Re:
Posted:
Sep 3, 2003 7:07 AM
in response to: Elrod, Kent
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Thanks for clearing that up!
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Re:
Posted:
Sep 3, 2003 2:22 PM
in response to: Elrod, Kent
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I remembered reading about this topic sometime ago in this NG where someone wondered why an isometric view set in a floating viewport in paper space did not print full size when the scale was set to 1:1. Juergen Palme had the answer - I think it was in the 2002 NG. Anyhow I eventually tracked down his post of 23rd March and seemingly if you want a true isometric scale of 1:1 then you have to set the viewport scale to 1.2247449. Here is a clip from his post: < Yes, isometric view is defined that the lines are 30/150° rotated. To get this result the viewpoint must be rotated 45° in the XY plane and arccos(sqrt(2/3)) = 35.26439...° from the XY plane. To get an 1:1 view you also have to scale the view with the factor 1/sqrt(2/3) = 1.2247449... > I have actually had to use Juergen's value a couple of times when I have modelled a product that I get my pupils to draw an isometric drawing from orthographic views. I then use the scaled up isometric view to print onto an acetate sheet I use to overlay onto the pupil's board drawing to check it for accuracy and mark their work. Rob Fowler. "Kent Elrod" wrote in message news:DB9D0C8A46BF4A4E68C55065BF229468@in.WebX.maYIadrTaRb... Jon, that is somewhat misleading. Because of the limitation of the tools
available to draw isometrics on the board (namely the few available
triangles) isometric drawings were traditionally drawn with the three
axonometric axes at 90 degrees, 30 degrees and 150 degrees. The definition of an isometric is " one is which all angles between the axonometric axes
are equal". So as long as the three axes are 120 degrees from one another
it is an isometric. We have come to think that there should always be a
vertical axes in an isometric, but again, that is due to the ease of drawing on a board. I started on the board so I know a little about that. Kent "Jon Kirkham" wrote in message news:E4441DD460279020054F7EE86472C969@in.WebX.maYIadrTaRb... I was taught two years ago that Isometric was a specific type of Axonometric drawing using 30 and 60 degree angles to define the projection. Was I
mislead?
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Posts:
5,183
Registered:
12/12/03
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Re:
Posted:
Sep 3, 2003 2:31 PM
in response to: robfowler
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To get this result the viewpoint must be rotated 45° in the XY plane and arccos(sqrt(2/3)) = 35.26439...° from the XY plane. >To get an 1:1 view you also have to scale the view with the factor 1/sqrt(2/3) = 1.2247449... << Wha?? |
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Re:
Posted:
Sep 3, 2003 7:15 PM
in response to: old-cadaver
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To get this result the viewpoint must be rotated 45° in the XY plane
and arccos(sqrt(2/3)) = 35.26439...° from the XY plane. <Unnecessary and much less accurate than using a unit offset
viewpoint, like 1,-1,1 OLD-CADaver, Jurgen is out in left field on this
one. As you say using viewpoints like 1,-1,1 or even simpler, using #D
views and picking one of the iso views is all that is needed. >To get an 1:1 view you also have to scale the view with the factor
1/sqrt(2/3) = 1.2247449... << Wha?? Old, This is true. In order to obtain a true
length for dimensioning purposes the view port view will have to be scaled
up. This is because autocad is creating a true ISOMETRIC PROJECTION, and
by definition the projection is showing the length of lines shortened.
When you take a 1 inch cube and rotate the view to an isometric view then the
lines are no longer parallel to the plane of projection, causing the lines
to be viewed as shorter than they really are. Everyone, rather than believe any of us, pull out a
drafting book and look this stuff up. I think the only way to discuss
technical issues is to for everyone to agree on and use the industry accepted
terms and methodology. I haven't looked at many drafting books, but I am
sure they will all agree on the basic concepts of Axonometric projection
drawings. Kent |
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Posts:
5,183
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12/12/03
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Re:
Posted:
Sep 4, 2003 4:36 AM
in response to: Elrod, Kent
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To get an 1:1 view you also have to scale the view with the factor 1/sqrt(2/3) = 1.2247449... << Wha?? Old, This is true. In order to obtain a true length for dimensioning purposes the view port view will have to be scaled up. << Ohhh I see, dimensions in PAPERSPACE, right? Sorry, I wasn't keeping up. We dimension ISOs in MODELSPACE (With lisp functions to make it easy), so we're not dimensioning the project points, but the actual element. No viewport scaling (other than to fit the sheet) is required. |
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12/12/03
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Re:
Posted:
Sep 3, 2003 6:52 AM
in response to: Richardson, Randy
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Since a 3" line that would normally be shortened because it's angled away from you is drawn fully 3" long, and since you would never see it that way in reality, I say it's not an accurate depiction.<< hmmm... We only "see" in "perspective", so an orthographic view does not portray reality either, and yet most would say they are an "accurate depiction" of the object. "Accuracy" is the dimensional value, so a true isometric projection is "accurate", it is a "depiction" of the object as well. Therefore, to my mind, it is an "accurate depiction". An INaccurate depiction would have "some" elements that were exaggerated or inaccurate dimensionally. |
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Re:
Posted:
Sep 3, 2003 7:06 AM
in response to: old-cadaver
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Ha! Not only are you right, but I was even
thinking most of the same things that you just mentioned when I wrote
this. I do think that getting in all the modifiers and exceptions added to
a sentence sometimes obscures rather than illuminates, though, so
I simplified, arguably oversimplified. So thanks for getting me
all straightened out. -Randy
>Since a 3" line that would normally be shortened because
it's angled away from you is drawn fully 3" long, and since you would never
see it that way in reality, I say it's not an accurate depiction.<<
hmmm... We only "see" in "perspective", so an orthographic view does not
portray reality either, and yet most would say they are an "accurate
depiction" of the object.
"Accuracy" is the dimensional value, so a true isometric projection is
"accurate", it is a "depiction" of the object as well. Therefore, to my mind,
it is an "accurate depiction". An INaccurate depiction would have "some"
elements that were exaggerated or inaccurate
dimensionally.
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Posts:
5,183
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12/12/03
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Re:
Posted:
Sep 3, 2003 7:27 AM
in response to: Richardson, Randy
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I think what we have is a subtle difference in terminology at play.
ISOMETRIC DRAWING and ISOMETRIC PROJECTIONS are two phrases that have been used for centuries to describe two kinds of 2D depictions of 3D objects. (PROJECTIONS being a kind of orthographic projection in which true lengths are foreshortened based on the axis of projection.)
And ISOMETRIC VIEW, which is AutoCAD's (and some others) phrase for a view of a 3D object, that when plotted will result in an ISOMETRIC PROJECTION.
But hey, that's just my viewpoint :O)
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Re:
Posted:
Sep 3, 2003 7:37 AM
in response to: old-cadaver
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OK. What an education this has been for
me.
I
think what we have is a subtle difference in terminology at play.
ISOMETRIC DRAWING and ISOMETRIC PROJECTIONS are two phrases that have been
used for centuries to describe two kinds of 2D depictions of 3D objects.
(PROJECTIONS being a kind of orthographic projection in which true lengths are
foreshortened based on the axis of projection.)
And ISOMETRIC VIEW, which is AutoCAD's (and some others) phrase for a view
of a 3D object, that when plotted will result in an ISOMETRIC PROJECTION.
But hey, that's just my viewpoint :O)
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Posts:
204
Registered:
11/25/03
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Re:
Posted:
Sep 3, 2003 7:39 AM
in response to: old-cadaver
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Can open, worms everywhere.
At any rate, my drawing that I am using is in my terminology is an isometric view. The drawing is not to scale and is not a true isometric drawing or projection. (meaning the view was not created by projecting lines from top view, left view, right view etc.)
So although I do want dimension lines to dimension the drawing, the actual dimensions would not give the correct lengths due to it's angle, as you all have been discussing. I simply need a dimension line, and a quick way of doing it without adding an angle to the dimension and playing around with it.
So I found a lisp routine that is document in these news groups called ISODIM.LSP, which does exactly what i need it to do. The text however isn't exactly correct but it does the job.
The above discussions however were quite interesting.
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Posts:
5,183
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12/12/03
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Re:
Posted:
Sep 3, 2003 8:25 AM
in response to: kb
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Sorry, (frantically stuffing worms back in can), I thought JONESR answered your question earlier. But to elaborate, use DIMALIGNED, with your SNAP STYLE set to ISO. You can override the default text when placing the dim's if needed. ISODIM is a pretty slick solution, but what is wrong with the text? It's value? or it's appearence??
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Posts:
204
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11/25/03
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Re:
Posted:
Sep 3, 2003 10:42 AM
in response to: old-cadaver
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Thanks for the info. It's appearence isn't quite right. It's close but not perfect.
Maybe I'll try JONESR's method as just for a different perspective.
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Posts:
5,183
Registered:
12/12/03
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Re:
Posted:
Sep 3, 2003 11:29 AM
in response to: kb
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Change the slant angle and width of the text in the STYLE dialog box.
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Posts:
204
Registered:
11/25/03
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Re:
Posted:
Sep 4, 2003 7:48 AM
in response to: old-cadaver
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But will I have to create a new dimension style for each different isometric plain? (top, right, left)
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Posts:
5,183
Registered:
12/12/03
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Re:
Posted:
Sep 4, 2003 8:27 AM
in response to: kb
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Or dimension everything using one DIMSTYLE, then override the textstyle for each group of dimensions (top, left, right).
(That's one of the reasons we annotate the 3D model in MODELSPACE)
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