# TheSwamp

## CAD Forums => CAD General => The Third Dimension => Topic started by: Mark on July 19, 2005, 11:00:00 AM

Title: Pipe slicer
Post by: Mark on July 19, 2005, 11:00:00 AM
Need some help from you 3D guys. I'm trying to cut off part of a cylinder but I've no idea how. I can create the cylinder (culvert pipe) without problem but I can't figure out to slice if off. What I have is a mitered end section (concrete placed at the end of a culvert usually at about a 65 degree angle) at the end of a culvert pipe (the thing in a ditch that typically has a driveway over it).

See image for detail [ http://www.theswamp.org/screens/mark/screen_shots/slice_cylinder.png ]

Thanks.
Title: Pipe slicer
Post by: Keith™ on July 19, 2005, 11:29:51 AM
in your front view, where you show your 3d polyline, draw a line at the angle you want the object cut off, set the UCS to that line, then slice along the ZX plane saving the piece you need (or both)
Title: Pipe slicer
Post by: Mark on July 19, 2005, 12:04:36 PM
Yea man ... !!

Thanks Keith.
Title: Pipe slicer
Post by: Keith™ on July 19, 2005, 01:48:54 PM
you are very welcome .. UCS will quickly become your best friend when working in 3D ...
Title: Pipe slicer
Post by: t-bear on July 19, 2005, 01:58:35 PM
3-point UCS...........awsome for running tubing systems and piping runs.......
Title: Pipe slicer
Post by: CADaver on July 19, 2005, 02:32:46 PM
While UCS is an extremely useful command, it is not necessary in this case.  All that is needed are the start point of the slice above the "invert" and the angle from the XY plane (25 deg) and the SLICE command.

The following assumes the start of the slice is 4" above the B.O.P., hence the "From" "QUA" "@0,0,4"

The second point on the slice only needs a vector of any magnitude, so I used @12<0<25.  The 12 is the magnitude, the first angle "<0" is IN the XY plane and the second angle "<25" is FROM the XY plane.

The third point is just a vector relative to the second point, @22<90 would work, as would @0,12 or @ 0,1

Then just select the portion to keep.

SLICE
Select objects: 1 found

Select objects:
Specify first point on slicing plane by
[Object/Zaxis/View/XY/YZ/ZX/3points]
<3points>:  From
Base point:  Qua of <Offset>: @0,0,4

Specify second point on plane: @12<0<25

Specify third point on plane: @0,12

Specify a point on desired side of the plane or [keep Both sides]: B[/list:u]

Once you get familiar with 3D this kind of slice manipulation becomes second nature.  For the neophyte, the UCS method is easier, if more steps are required.
Title: Pipe slicer
Post by: Keith™ on July 19, 2005, 02:44:44 PM
hey ... watch the name calling bud ... and yes the UCS command IS easier and faster than attempting to calculate offsets ... Stick with the UCS it is better .. I don't care what CADaver says .. :P
Title: Pipe slicer
Post by: CADaver on July 19, 2005, 02:51:27 PM
Quote from: Keith
hey ... watch the name calling bud ... and yes the UCS command IS easier and faster than attempting to calculate offsets ... Stick with the UCS it is better .. I don't care what CADaver says .. :P
If you know enough to set the UCS, that is all you need for slice.

And where I am, one command is easier and faster than 2 commands... but I understand that certain parallel universes have it the other way round. :wink:

BTW, no offsets were calculated at all.
Title: Pipe slicer
Post by: Keith™ on July 19, 2005, 02:58:59 PM
I live on multiple planes .. thus it is easy for me to navigate any number of planes ... and while there are 2 commands, I find it faster to make 2 or 3 additional clicks rather than type in 8 or 10 characters .. it is all about number of motions .. not number of commands ... ;)
Title: Pipe slicer
Post by: t-bear on July 19, 2005, 03:00:59 PM
what Keith said..........first y'gotta figure all them angle thingies out, then y'gotta TYPE 'em!  Gimme a couple'a clicks any time!
Title: Pipe slicer
Post by: CADaver on July 19, 2005, 03:01:12 PM
Quote from: Keith
I live on multiple planes .. thus it is easy for me to navigate any number of planes ... and while there are 2 commands, I find it faster to make 2 or 3 additional clicks rather than type in 8 or 10 characters .. it is all about number of motions .. not number of commands ... ;)
How did you define that particular UCS with just a couple of clicks?
Title: Pipe slicer
Post by: Keith™ on July 19, 2005, 03:08:44 PM
Well, in Mark's example, there is already an object at the desired angle ... click <align UCS to object> click <object>

voila ~ ucs is aligned

slice

click <slice> click <object> (kbd) [spc] ZX [spc] click <object> click <object> ~ done
Title: Pipe slicer
Post by: CADaver on July 19, 2005, 05:02:50 PM
Quote from: t-bear
what Keith said..........first y'gotta figure all them angle thingies out, then y'gotta TYPE 'em!  Gimme a couple'a clicks any time!
NOTHING needs to be figured out, the angle is already known.  If you know enough to set the UCS, you know enough for the slice.
Title: Pipe slicer
Post by: CADaver on July 19, 2005, 05:07:03 PM
Quote from: Keith
Mark's example,
is a 2D representation of what he wants.  If you know enough to draw the line, you know enough to make the slice, without drawing the line or changing the UCS.  NOTHING to figure out, nothing additional to key in.
Title: Pipe slicer
Post by: Keith™ on July 19, 2005, 05:35:38 PM
You need to read the post again .. besides, if it is ONLY a 2d representation, then he doesn't need to slice anything now does he.

Sorry .. this is one time you are way off base .. because your method is not as efficient as aligning the UCS to an existing object ...
Title: Pipe slicer
Post by: CADaver on July 19, 2005, 08:48:01 PM
Quote from: Keith
You need to read the post again .. besides, if it is ONLY a 2d representation, then he doesn't need to slice anything now does he.
Maybe you need to look at the picture again.  It's a copy of a 2D drawing, otherwise the "plan view" of the "collar" would be elliptical.

Quote from: Keith
Sorry .. this is one time you are way off base .. because your method is not as efficient as aligning the UCS to an existing object ...
Nope, not this time either, if you have enough information to create the UCS, you have enough for the slice, fewer commands, fewer steps.  Not only more efficient, but MUCH more efficient.  No lines to then erase, nothing to figure, nothing additional.  Geez, just try it.  I did it your way for for some time, until I found a much more efficient method.
Title: Pipe slicer
Post by: Kerry on July 19, 2005, 09:06:20 PM
If it means anything, I do both.

.. Using a UCS depends on how often I need to come back to that plane, or parallel to it, or orthogonal to it. I use a UCS more often than not.

... Mainly because once it is established < blink of an eye > consistantly returning to the SAME plane is a breeze.
Title: Pipe slicer
Post by: Keith™ on July 19, 2005, 09:15:18 PM
typing with one hand is not efficient, unless you are left handed and can type with your right hand alone ... the keyboard is not setup to be efficient.

If I have to move my hand all around the keyboard, and move it off of the mouse to type various distances and bearings or enter 3d points as numerical data my time has become severly wasted.

Using your idea that typing it in is more efficient it is amazing that we even use the mouse pointer at all ~ after all, we could just type in the direction vectors, wouldn't that be more efficient?

I suspect that you are merely "stuck" in your way .. and it serves you well. If that is the case then so be it .. but please do not try to take away the tools that are available and simple to use .. indeed much easier to use ...
And while you are correct that the plan view would be 2d, because the slice is not elliptical, you must understand that a) he had not made the slice at that point b) I referred to the front view where he shows an existing 3dpolyline (which could conceivably be used as defining plane)
Bottom line is in less than 2 seconds I could slice it along that plane...but I couldn't even think what I needed to type that fast ....
So keep using that old keyboard ... and have fun with it
Title: Pipe slicer
Post by: CADaver on July 20, 2005, 01:31:13 PM
Quote from: Keith
typing with one hand is not efficient, unless you are left handed and can type with your right hand alone
I'm right-handed thats why I have the mouse in my left hand.  See mouse 3 buttons, see keyboard bunch of buttons, which needs the more adroit hand?  Mouse in left hand, right hand over numeric keypad (or do you not enter numbers when drawing?) is considerably more efficient than anything I've seen up to now.  But then I can use two hands a one time.

Quote from: Keith
If I have to move my hand all around the keyboard, and move it off of the mouse to type
Then you have an inefficient station setup, see above.

Quote from: Keith
various distances and bearings or enter 3d points as numerical data my time has become severly wasted.
How do you enter 3d data without entering the numerical data with the keyboard?

Quote from: Keith
Using your idea that typing it in is more efficient it is amazing that we even use the mouse pointer at all ~ after all, we could just type in the direction vectors, wouldn't that be more efficient?
Very often it is, if you take the time to design your station setup to be efficient.

Quote from: Keith
I suspect that you are merely "stuck" in your way
one of us is and I'm pretty sure it's not me.  We taken the time to do efficiency studies on station setups to find out the most efficient method of getting information into a drawing, and we measured the methods using 75-90 different operators.  Some worked better than others, and others took some getting used to.  But generally we found the one command was much more efficient than two or three, and drawing stuff that had to be erased later was a major waste of time.

Quote from: Keith
.. and it serves you well. If that is the case then so be it .. but please do not try to take away the tools that are available and simple to use .. indeed much easier to use ...
Not taking anything away (as I pointed out in my first post) just pointing out the "better" way.  If you wish to remain inefficient, carry on.  But if you wish a way that is CONSIDERABLY faster, just as simple and even easier, check out the method I posted.  Or just dismiss it out of hand as something "new".

Quote from: Keith
I referred to the front view where he shows an existing 3dpolyline (which could conceivably be used as defining plane)
Bottom line is in less than 2 seconds I could slice it along that plane...but I couldn't even think what I needed to type that fast ....
How did the line get there? To draw the line you have all the info you need to make the slice, without drawing the line.

So
My method is "make the slice"
Your method is draw a line, set a UCS, make the slice, erase the line

Bottom line is pretty apparent.

Quote from: Keith
So keep using that old keyboard ... and have fun with it
I do, thank you, being efficient is not only fun, but profitable.  But I understand some who can't use both hands at the same time, we make 'em spit out their gum before walking.
Title: Pipe slicer
Post by: Keith™ on July 20, 2005, 02:20:39 PM
I suppose I fall into that category of the inefficient fool that cannot type and chew gum at the same time, but I do know that I can draw pretty darn fast and I have yet to find anyone who can draw as fast as I do, or as efficient as I do .. be it through keystrokes, mouse, or tablet .. I am well versed in all of them.

The good thing about AutoCAD is that if something is to be done, there are a dozen or more ways to do it, each with their good points and bad points ... unfortunately I cannot get used to a left handed mouse, I have tried ... it is like putting a square peg into a round hole .. it just doesn't fit well, no matter how hard you try... heck I even worked with a guy once that had 2 mice, one for each hand, had tool palettes for keystrokes, and he could do anything with the mouse that you could do with the keyboard... so for me using the mouse, drawing and erasing lines, and setting UCS to object IS much more efficient, and for you to suggest that it is more efficient for everyone to use your method, is both wrong and an illogical use of your time. Conformance is fine, but brains process information, in this case the user must process the information required to make the task at hand as efficient as possible. That is where the error is in your "efficiency" standards. No 2 human brains are exactly alike, they all process information a little differently and as such it is the individual that must determine what is more efficient, and it just so happens that you find extensive use of the keyboard more efficient than pointing and clicking ... I am exactly opposite ..
Title: Pipe slicer
Post by: whdjr on July 20, 2005, 02:57:19 PM
...
So
My method is "make the slice"
Your method is draw a line, set a UCS, make the slice, erase the line

[sarcasm]hm...I didn't realize changing the UCS entailed drawing a line.  I always thought I selected an entity I wanted to use...[/sarcasm]
Title: Pipe slicer
Post by: CADaver on July 21, 2005, 06:50:29 AM
Quote from: whdjr
hm...I didn't realize changing the UCS entailed drawing a line.  I always thought I selected an entity I wanted to use
What entity are you going to select?  The only element in the drawing indicating the angle is the line.  How'd it get there without drawing it?  I don't have MagiCAD, I only have AutoCAD.
Title: Pipe slicer
Post by: CADaver on July 21, 2005, 07:01:16 AM
Quote from: Keith
I suppose I fall into that category of the inefficient fool that cannot type and chew gum at the same time, but I do know that I can draw pretty darn fast and I have yet to find anyone who can draw as fast as I do, or as efficient as I do .. be it through keystrokes, mouse, or tablet .. I am well versed in all of them.
you're gonna pull a muscle.

Quote from: Keith
I cannot get used to a left handed mouse, I have tried ... it is like putting a square peg into a round hole ..
Never HAD to, if you did, you would.

Quote from: Keith
and setting UCS to object IS much more efficient, and for you to suggest that it is more efficient for everyone to use your method, is both wrong and an illogical use of your time.
Tell me, how did the object get there for you to use in creating the UCS?  You had to draw it right?  What method did you use to draw it?  Nothing to click to, right?  Rather than drawing an object to set a UCS, just do the slice.  Doing so is both logical AND much more efficient.  Drawing something that later has to be erased (the object for your UCS) is both illogical and a waste of time.

Quote from: Keith
is where the error is in your "efficiency" standards. No 2 human brains are exactly alike, they all process information a little differently and as such it is the individual that must determine what is more efficient,
Nope we take that into consideration.  Just a very little training is sufficient for anyone without a "stuck in my old methods" mindset.

Quote from: Keith
and it just so happens that you find extensive use of the keyboard more efficient than pointing and clicking ..
Where did you get "extensive use" of the keyboard.  I merely used the same entries that you would need to create the line in the first place.  The difference is when I'm done the pipe is sliced, when you're done you have a line that will need to be erased later, and you still need to set a UCS and do the slice.  The efficiency is obvious.