Part Maker Tutorial
1. Part Maker Introduction 2. Geometry Files 3. Getting Started With Part Maker 4. Making Models in Part Maker
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Making a Model
Before going back to the run file, let's use one command here in Part Maker to show you how the syntax works and what you need to know about the program itself.
The MODIFY Command:
It is generally best to add camber to your decks before making the tanks, in case there are tanks which use a cambered deck for their tops. On this vessel there is no camber on the main deck, but the focsle deck has 50 cm. of camber. To add this camber, at the prompt type:
The word HULL should appear in the upper left corner of the box, below it the component and shape names. This means that Part Maker has located the component you are about to modify. If you got an error message, type the command again, making sure everything is spelled right.
You will also notice that the prompt has become two arrows instead of one. This is to let you know that you have not completed the MODIFY command and it is waiting for more information about the modification you want it to perform. Type in another line as follows:
CAMBER .5 @ -61.95, .5 @ -35.11
This means that a constant .5m camber is to be added to this component, at every station from 61.95m forward of the origin (minus always means forward) to 35.11m forward of the origin, which is the portion occupied by the raised focsle. This doesn't mean that the difference between deck edge height and centerline height will be 50cm at every station - only at the widest station then proportionately less, holding the same camber curve for all the other stations. If the focsle had been a separate component receiving camber for its entire length, only the first .5 would be necessary, the locations could be omitted. The type of camber in this case will be the standard camber curve. Circular, parabolic and straight camber curves are also available.
You are through with the camber statement and can inform Part Maker that the modify command is ready to execute. Do this by entering a single forward slash / on a line all by itself.
As the camber is being added to the stations, a message appears in the box at the top of the screen, informing you of the progress - though if your computer is fast it will probably be too quick to see. When the cambering process is complete, the box should be clear. Part Maker is now ready to receive another command, and your window should look something like this:.
Go ahead and type QUIT. This will get you out of PM. Now, if you click on the Wizard menu on the top of the screen, you can select 'Executive' when the box drops down to restart the wizard.
Note that you are still using the PMDEMO project, so all you have to do to edit your run file again is click 'Edit'.
When you left Part Maker, you didn't write your geometry file, so the camber was left unchanged. Why don't we add the commands we used here in the run file. That way, if we make mistakes they are easy to see, find, and correct. Type them after the READ command but before the END command.
CAMBER .5 @ -61.95, .5 @ -35.11
The WRITE Command:
After you have made all your tanks and appendages, you should save your work by writing the results to a new Geometry File (PMDEMO.GF2 in this case) with the WRITE command. This command should always go right before quitting Part Maker, so let's add the command so that your run file now looks like this:
The CREATE Command:
The aft portion of the focsle is actually supposed to be a pair of wings with an open space between. This is how to make a deducting component to account for the open space.
You need to use the CREATE command, since you are making a new component under the HULL part. Enter the command after the closing / of your last Part Maker command:
On the very next line enter the word DEDUCT. This prepares Part Maker for the fact that it is going to be a deducting component.
Next, begin specifying the shape to be deducted by using the ENDS statement. It runs between 32.67 forward and 41.82 forward of the origin (Remember forward is negative):
ENDS -32.67, -41.82
The space is also bounded by bulkheads which are 3.675 meters off centerline, so you can say:
The bottom of the shape is at main deck level, which is 5.8 m. above baseline, so type:
The top can remain unspecified, since you are going to 'fit' it to the HULL component and that will supply the top. Or you could give a top value that is higher than the focsle deck. But leaving it unspecified means it will be at infinity, which is certainly high enough and accomplishes the same thing.
Also, you have to let the program know that you want this thing to be fit to the HULL component. So the next statement will be:
While DEDUCT must be placed immediately after the CREATE command, the order of the other four statements you have just entered (ENDS, OUTBOARD, BOTTOM and FIT) is not important. They are not acted upon until the command is completed with the final slash on a line all by itself.
Many times when you are developing a model, you may want to see it graphically. This is one of the strong points of the run file. Because everything is listed out already, you don't have to retype things to get back to a certain spot-- all you have to do is run the file.
DISPLAY: To display your geometry from the run file, you must type 'DISPLAY'. This IS NOT a Part Maker command, so it must be run from the GHS command prompt, or in your run file after you quit Part Maker.
If you're still following along, the complete set of commands in your run file will look like this:
Let's take a look at your progress. Save and close your run file, and press the pretty green 'Run' button on your Executive Wizard. This will run your file, which should open up the display and look like this:
You should see a new component at the aft end of the focsle, nicely aligned with the main deck and fitted right up to the focsle deck, including the slant. Now, press the down arrow once. This removes the highlight from the recess component and lets you see its true red color, indicating that it is a deduction.
If you wish, you can look at it in the Axonometric and Body Views by pressing the TAB key. When you are finished , press ESC and ENTER to quit the display and return to the Executive Wizard.
The DELETE Command:
If, for any reason, you want to start over with the recess component, you can do two things: You can modify the run file to accommodate any changes, or you can enter part maker with no run file, delete it and try again. To delete a component, enter the command DELETE followed by the name of the component to be deleted on the same line. In this case it would be:
This is a single line command, and does not require a '/' to close it. Because we are using a run file, there is no need to delete the component, so we will be leaving it out for this demonstration. Regardless, it is a handy tool to know.
Let's go back to editing your run file and build the bow thruster with another CREATE command. Again it is a deduction, so type:
There is a special statement for making cylindrical-type shapes called the CYLINDER statement. Go ahead and type it out:
CYLINDER -50.5,0,1.6, -50.5,10,1.6, 1.5
What this means is that a central axis passes through the two end points (-50.5,0,1.6 and -50.5,10,1.6) of the cylinder, and its diameter is 1.5 meters. As always in GHS, the order of the coordinates given is longitudinal, transverse, and vertical. Since only the transverse coordinate varies, you can tell this cylinder's axis runs athwartship. Note that you have only given the starboard half (positive offsets are starboard), but that is as good as giving both sides, since you have declared it to be a centerline component. The length of this starboard half is 10 meters, which is quite a bit wider than our boat is at that point, so you need to fit it to the HULL component. The fitting process will chop off the excess. So type:
Close the command with a '/' on a line by itself.
If you wish to pop into DISPLAY and have a look at the result, go ahead and run your file (make sure you save it!). Otherwise, we will get started with the next part immediately.
Now let's make a tank -- a complex one with a thruster running through it.
There are a couple of deep tanks with their common transverse bulkhead coming right down on the thruster tube. It sounds tough but it is really easy. So here we go with one of the deep tanks. Type:
There are two things to note about this command. The first is that only the part name is given and the second is that the part name ends in a '.S'. This means that you are creating a separate part, not a component under the HULL. Part Maker assumes that each new part created is a tank unless you tell it otherwise. The 'DEEP1.S' means that the tank is to be named DEEP1 and that it is to be on the starboard side of the vessel.
Two statements you will usually want to include when making a tank are PERMEABILITY and CONTENTS. Type:
This means that 95% permeability is to be allowed (not counting the thruster tunnel, which you will be deducting soon). If no permeability statement is given, Part Maker assumes 98.5% permeability.
Since this is a fresh water tank, you should indicate that by typing:
The 'FW' is recognized by Part Maker and expanded to the words 'Fresh Water' and the specific gravity is set at 1.0. The User's Manual lists all of the allowable abbreviations and shows how to put in your own specific gravity values when necessary.
Since this tank runs longitudinally from 54m forward to 50m forward, you can make the ends statement
Now, the top is at the main deck level of 5.8, so enter:
Since it goes all the way to centerline and down to the bottom shell, that's it for the main part of the tank, except for fitting it to the hull, so type
Notice that since you are fitting to a component belonging to another part you gave the full formal component designation (actually, since there is no ambiguity in this case, you could have said simply FIT HULL and Part Maker would have figured out what you meant).
Now, you could end the command and create the thruster deduction with a separate CREATE command, but it saves typing to hook it on right here. So type the word DEDUCT on a line by itself. This tells Part Maker that you want to introduce another component, a deducting one, and to go ahead and process the previous statements.
Now you can put in that thruster tube again using the exact same Cylinder statement
CYLINDER -50.5,0,1.6, -50.5,10,1.6, 1.5
But since part of this tube bulges out into the next tank, you need to slice it off at the 50m bulkhead. One good way to do this is simply to fit it to the main part of the tank. All you have to do is say:
Now you can close the command with a '/'.
Before you go to see how it turned out, let's make a port-side tank just like this one. Type:
Your run file and geometry should look like this:
See whether yours looks the same. Note that in DISPLAY, the SPACE BAR is very useful for looking at successive parts, especially in the Axonometric and Body Views.
The Hull component that you have been using does not include shell thickness, so our tank has its boundaries at the inside of the hull shell. After you have finished making the tanks, you can easily add the shell thickness to the hull with another MODIFY command. The plating on this vessel happens to be 1.2 cm., so the shell command would be:
Since the skeg is a separate component, it was not touched by the MODIFY command. If you want the same shell thickness on the skeg, you must do another MODIFY for it, like this:
And while you are at it, you may as well fit the SKEG to the HULL component in order to eliminate the overlap caused by adding the shell.
If you had put the shell on before the tank was fit to the hull, the results would have been the same. Part Maker knows whether there is a shell and how thick it is, so it takes that into account when fitting tanks. It is recommended, however, that you fit the tanks before adding the shell, since the FIT process requires less processing when no shell is present. Like camber, shell thickness can be replaced simply by doing another MODIFY with a different shell thickness value.
When you are all done and finished, your display and file should look like this:
We hope this tutorial has been helpful in getting you started using Part Maker. It is a very powerful, yet easy program to use. You can access information on additional commands and the program via the 'HELP PM' command using the GHS prompt, or look in the User's Manual.
Back to the Beginning
1. Part Maker Introduction
2. Geometry Files
3. Getting Started With Part Maker
4. Making Models in Part Maker
Copyright (C) 2011, Creative Systems, Inc.