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CPM - CONVERTING TO METRIC FROM IMPERIAL MEASUREMENTS
(ENGLISH FRACTIONS)
Currently the CPM automated custom-sized pattern drafts
do not run properly when metric measurements are added. This appears
to be due to the automatic addition of ease to certain measurements.
If you create patterns using the Imperial measurement system and wish
to convert them to the metric system, the instructions follow below.
AutoCAD actually thinks in terms of UNITS. It doesn't
really make any difference what you call a unit, it draws, in its mind
as a UNIT. The time that it becomes important to tell AutoCAD a specific
size of unit is when you are going to plot the drawing out. The part
of the software that interprets the "non-denominal unit" to a specific
UNIT system is the "drivers" that talk to the printer or the plotter.
Most plotter drivers will accept and plot what ever unit system you
tell it to use. Those unit system specifications need to be "embedded"
in the drawing file that your are going to plot. You will also need
to specify the same unit system in a "plotter configuration".
The best method for doing this is to start by creating
a new "drawing page" that is set up with the metric scale. Use the
Wizard at the start up to specify "decimal units", set the size of your
drawing area, and if desired, set up a "tiling grid" for plotting to
a plotter that is smaller than the total drawing page.
NOTE: In the CPM program the "computer" "talks" to you
through the "command prompt area" at the bottom of the program window.
It is possible that when you first start up the program that this area
will appear to be only a one line high white area running the width
of the program window. If you point your cursor at the "window frame
bar" just above the blank white area you will see your cursor turn into
a vertical line with arrows at each end. While holding your left mouse
button down you can drag the frame up and reveal 3 lines of space in
the command prompt area. You will need this command prompt area arranged
like this for the following steps, in order to be able to see the command
prompts.
On converting to metric patterns from Imperial
measurements (English inches and fractions).
To convert an Imperial unit pattern to metric:
You will need to INSERT a pattern generated by CPM from english measurements
into the new metric drawing page you have created.
1. Select the INSERT command is under the VIEW menu. You will
see in the command prompt line:
1.1. insert Block name (or ?):
1.2. type the address of the pattern file you want. (example:
c:\cpm\patterns\pattern.dwg) and ENTER.
1.3. At Intersection point: type 0,0
2. Then Zoom Extants so you can see the whole thing.
3. Go into the Control Layers under the MODIFY MENU
3.1. In the Control Layers Control Box, Click on the little padlock
symbols that look locked to unlock them.
3.2. Close the window.
4. Erase page border and margins and the E size title header.
5. Run Delete Drafting lines under the OPTIONS menu.
6. Go back into the Control Layers window and lock the margin
and Dwgborder layers. (don't forget to have any important patterning
points that reference to the drafting lines already marked before you
delete the drafting lines.)
7. Next start the SCALE command (under the RESIZE menu)
7.1. Select the entire pattern with a window.
7.2. Select any point as the base point.
7.3. Then type in .03937 as the Scale factor and enter.
7.4. You will see the pattern pieces become tiny on the screen.
8. Now Move the newly tiny pattern... select with WINDOW.
8.1. Select any base point within the patterns and drag them down
to the tiny little metric drawing page.
8. 2. Make the displacement point anywhere in the metric drawing
page area.
9. Now ZOOM EXTENTS - the on screen view will now frame the
metric drawing area.
10. Move the pattern pieces again by selecting with a window,
but this time select the lowest left corner of the pattern and place
it within the page exactly as you want it.
Now you are working in metrics.
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If you want to take a pattern from metrics, back to English fractions
and inches, you would do the same, but in the other direction... when
you get to the INSERT command, type in 25.4 as the Scale factor.
To Create a New Drawing Page Using Metric
Units:
1. At the start-up of CPM, use the Wizard to create a new page.
1.1. Select the Decimal option for Units, keep the default 4 decimal
places after the decimal point.
1.2. Then set up your area. The area you set up should sized in relation
to the plotter you are going to use. If you are using a large architectural
size plotter (E or D size in American standards), then you need to
make your drawing page area that size. If you are using a smaller
plotter, then you will want to make the drawing page area a multiple
of that size and "tile" it with rectangles that fit the size of your
plotter.
2. Next set up the drawing layers. From the MODIFY menu select
CONTROL LAYERS. This pops up the Line and Linetype
Properties control window. The Line properties are:
ON, Freeze in All Viewports, Freeze in Current Viewports, Freeze
in New View Ports, Lock, Color, Linetype. You will probably never
use the Freeze properties in pattern making. These properties are useful
when doing complex engineering or architectural drawings, or 3D drawings.
What you will be using are ON, Lock, Color and Linetype. You can drag
the "title sections" for each column of properties at the top of the
window to minimize the space taken up by the freeze properties to make
the titles of the properties you will use display better. Also take
note of the CURRENT button that is in the upper center of the window.
Immediately on it's right should be the number 0 (zero).
2.1. Click on the NEW button on the right
side of the window. You will see a new Layer appear in the layer list
with the name highlighted. Type in border as the
name for the new layer. Repeat this to make a tile
layer.
2.2. Make the color of the tile layer CYAN.
2.2.3. Click on the square in the Color column of the tile
layer. This pops up a color selection window.
2.2.4. Click on the light blue color in the Standard Color
bar at the top left of the window. Click on OK
to accept the selected color.
2.2.5. Click on OK in the Layer Properties
window to close it.
3. Next create a rectangle that is the border of your new drawing
page. From the DRAW menu click on RECTANGLE.
3.1. You will see in the command prompt area, at the bottom
of the CPM window:
Chamfer/Elevation/Fillet/Thickness/Width/<First corner>:
type in 0,0 for the First corner
and type ENTER.
3.2. You will see in the command prompt area:
Other corner:
Type in the x,y co-ordinates for the upper right corner of
your new drawing page. For example: for a rectangle that is 1 meter
wide and 1.5 meters high would be typed in as 1,1.5
3.3. You may not see anything happen on the screen after you
ENTER. This is not a problem. On the VIEW menu, click on ZOOM
EXTENTS. You should now see the rectangle framed on the page.
4. Now move the border line to a different drawing layer and
lock it, so it will stay in place while you work on your drawing pattern.
4.1. From the MODIFY menu select CHNG PROPERTIES
to fly out the menu and select CHNG LAYER. You will
see in the command prompt area:
_chng prop
Select objects:
4.2. Click the cursor on some point on the border rectangle
you have drawn. You will see in the command prompt area:
Select objects: 1 found
Select objects:
Change what property (Color/LAyer/LType/ltScale/Thickness)
? _la New layer <0>:
4.3. Type in the word Dwgborder and ENTER.
You will probably not notice any change in the drawing page itself.
Again you will see:
Change what property (Color/LAyer/LType/ltScale/Thickness)
? _la
ENTER and ENTER again to end the command.
4.4. Next open up the Layer Properties window again. (Control
Layers under the MODIFY menu) Click on the little "open padlock"
icon in the Dwgborder layer row. You should see it
"close". This means the layer is now locked. The CURRENT LAYER
should still be 0 (zero)
5. Turn on the grid dots. On the OPTIONS menu select GRID
to fly out the GRID menu and click on GRID#. If you
type in .5, that will make the grid at 50centimeters increments. You
will need to determine for yourself what you want the interval to be.
We suggest .01.
6. If you are setting up a drawing page with "tiles" (the size
of the page your plotter prints out), the next thing to do is to set
up the "tile grid".
6.1. First change the color you are drawing with (which should
look black on your screen.). This way you can make your tile grid
a color that is different from the colors of lines used in your pattern
drawings. From the DRAW menu select SET-COLOR to fly out the color
menu and then select CYAN (this is light blue).
6.2. Next change the layer that you are drawing upon. Open
the Layer Properties window. Select to highlight the tile
layer and click on the CURRENT button. You should see the word tile
appear immediately to the right of the CURRENT button.
6.3. Draw a rectangle that is the width and height that your
plotter will print on one page. Again make the starting corner 0,0.
6.4. Next "grid-off" the rest of the drawing area by making
multiple copies of the original rectangle. From the MODIFY menu select
COPY. You will see, in the command prompt area:
Select Objects:
Pick the tile sized rectangle you have just drawn with the "pick box"
cursor and then click the right mouse button to stop selecting.
6.4.1. In the command prompt area your will
see:
<Base point or displacement>/Multiple:
6.4.2. Type m and ENTER. You will see:
Base point:
6.4.3. From the SNAPTO menu select Snapto INTER(section). The
cursor will become cross hairs.
6.4.4. Select the lower left corner of the "tiling rectangle".
As soon as you see the magenta X appear click the left mouse button
to select the corner. You will see:
displacement:_int of Second point of displacement:
6.4.5. From the SNAPTO menu select Snapto INTER(section). Now
point to another corner. You will see a "shadow" of the original rectangle
following the cross hairs. When you see a magenta X appear at the
new corner position, click the left mouse button to select that corner.
Repeat these steps as many times a necessary to completely tile your
drawing area.
6.4.6. Once you have all the tiles in place, go back into the
Layer Properties window. Lock the tile layer. Select the 0 layer and
make it CURRENT.
7. SAVE the new drawing page format as a template.
7.1. From the FILE menu select SAVE AS. This
pops up the Save Drawing As window.
7.2. Pop down the menu list for the Save as Type
area and select Drawing Template (*.dwt)
7.3. In the file name area, type in a name for the file. The
file must have the suffix .dwt.
7.4. "Browse" to show the computer to save the file in the
Template folder (directory).
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