User's Guide: GemCad for Windows

1 GemCad for WindowsVersion 's GuidebyRobert W. StricklandSeptember 17, 2002 Copyright , 2002 Robert W. StricklandAll Rights document may not be copied or redistributed in any form, printed or electronic, except as part ofthe complete GemCad shareware distribution, without the written permission of the technical support (registered users 892 1887In honor of Walter Carss, a world class faceter, friend and 's Guide: GemCad for Windows1 Table of ContentsOverviewQuick Start Tutorial: Proof Cutting a Standard Round BrilliantScreen LayoutFour ViewNew Facet Info BoxSpin ViewCutting Instructions ViewToolbarStatus BarMenu BarMenu CommandsFile MenuEdit MenuView MenuPreform MenuRaytrace MenuHelp MenuAdvanced Tutorial: Design ExerciseAppendix A: GemCad for DOS Command EquivalentsAppendix B: Answers to Frequently Asked QuestionsAlphabetical IndexAcknowledgementsMany thanks to:Dave E.)

2 Wilson of Dewsoft, Inc. for his expert assistance with Windows L. Gartner for help with Windows programming, the print command, Windows Registry, andlots Attaway for his VRML export code and help getting started with the other file menu Heitland of Vancouver Island for testing and numerous 's Guide: GemCad for Windows2 OverviewGemCad is a computer aided design (CAD) program for faceted gemstones. It runs under Windows 95or later on PC compatibles with screen resolution of at least 800 x 600. GemCad simulates a facetingmachine and shows you accurate 3 D views of the stone. GemCad understands symmetry, so youtypically have to cut only a fraction of the facets to get the full design. GemCad can follow paths oflight rays through the stone to allow you to optimize a design to minimize light loss. The end product isan accurate faceting diagram that shows several views of the stone with accurate angles, indexes program has three main purposes:Proof cutting an existing diagram.

3 Proof cutting a design on the computer allows you to checkthe accuracy of the diagram and discover pitfalls before wasting valuable Editing a diagram. You can take an existing diagram and modify it to optimize its opticalperformance for different materials. You can scale a diagram to make it fatter or skinnier to fit acertain piece of Designing a stone from scratch. Advanced users can use GemCad to create new frees the user from the tedious calculations required to determine GemCad for Windows can open files made by GemCad for DOS, and the DOS GemRay can openfiles made by GemCad for doesn't model curved surfaces or notches but is limited to convex designs that can be cut onany faceting you have the Datavue II database of facet designs installed on your system, GemCad can access can find current information about GemCad at DesignsGemCad's setup program should have installed a number of sample designs on your system.

4 Unlessyou gave it a different location, these should be located in the folder:C:\Program Files\GemCadWin\DesignsQuick Start Tutorial:Proof Cutting a DesignWhy would you want to proof cut a design on the computer?If you have a diagram that you have never cut before, proof cutting will verify that the angles andindexes on the diagram will produce the design as pictured. This is particularly valuable when cuttingdesigns created before computers. Even for diagrams that are accurate, it is easy to get lost becausethe design changes drastically as facets are cut. If you are cutting to the wrong reference on the stoneor looking at the wrong facet, it's easy to get the cut it and cut it, and the facet is still too big the cutting sequence is not specified, or you and the designer have different opinions aboutthe cutting order. Some designs become meet point designs if the steps are cut in a different bottom line is that proof cutting on the computer can save you valuable rough and increase 's Guide: GemCad for Windows3To summarize, proof cuttingverifies the accuracy of the diagram verifies the cutting order shows how the design looks after every step Here is a diagram of a Standard Round Brilliant.

5 The tutorial below won't refer to this diagram. It's justfor reference to show you the finished for = + 16 girdles = 73 facets8 fold, mirror image symmetry96 indexL/W = T/W = U/W = = C/W = = 03 09 15 21 27 33 39 45 51 57 63 69 75 81 87 03 09 15 21 27 33 39 45 51 57 63 69 75 81 87 96 12 24 36 48 60 72 03 09 15 21 27 33 39 45 51 57 63 69 75 81 87 96 12 24 36 48 60 72 06 18 30 42 54 66 78 TableUser's Guide: GemCad for Windows4 First, make sure all ofGemCad's Windows arevisible. Your display shouldlook something like the figureon the right. (The colors andwindow style might vary withthe version of Windows andthe color choices you havemade in the Windows controlpanel.) If all of these windowpanes are not visible, movethe mouse pointer over thevertical and horizontalseparators between thewindow panes, press the leftmouse button, and drag theseparators one at a time untilyour display looks somethinglike the example at the you have trouble with thisstep, skip down to theScreen Layout will enter much of theinformation for new facets into the New Facet Info box.

6 The next step is to set the symmetry to 8 fold,mirror image. This is the default. If you have changed the symmetry, click in the Symmetry box andtype in 8. Make sure the mirror box has a check mark in it. If you have selected a different index gear,change back to the default 96 by cutting the girdle facets. Type 90 in the Angle box and 3 in the Index box. Then click theApply button (which might be instead labeled Cut Facet). User's Guide: GemCad for Windows5 You should then getsomething like the figure onthe right. GemCad knows tocut all 16 girdle facetsbecause of the gray facets are theedges of the block of rough. If you don't get this16 sided shape, press theUndo button on theToolbar and try again. Movethe mouse pointer asindicated by the crosshairs inthe screen shot at the click with the left mousebutton. The Point on Edgedialog box will pop up.

7 Clickthe Use to Cut button. Thispoint will establish the planeof the girdle and the depth ofcut for the break facets. Enteran angle of 42 and in indexof 3 and click the Applybutton. GemCad will cut 16break facets, making a , move the cursor asshown in the figure at theright, as indicated by thecrosshairs and the small redcircle o. Once the pointergets close enough, the redcircle will appear under thecrosshairs. Click with the leftmouse button and click theUse to Cut button. Enter anangle of 41 and an index of96. Click the Apply button,and GemCad will cut 8 mainfacets. This completes the Edit/Transfer menucommand or click the transferblock button on theToolbar to transfer the 's Guide: GemCad for Windows6 Your stone should look likethe figure on the right. Nowwe are ready to cut the crownbreak facets and establishthe girdle thickness.

8 Movethe mouse pointer as shownin the screen shot to theright, just above the girdleline. The whole girdle facetshould be highlighted ingreen. If only a single edge ishighlighted, move the cursoraway from the edge until thefacet is highlighted. Thispoint will establish the girdlethickness. Click with the leftmouse button and click theUse to Cut button. Enter anangle of 34 and an index of3, click the Apply button andGemCad will cut 16 crownbreak facets:Now we are ready to cut thecrown main facets. Move themouse pointer as shown bythe red circle. This should beat the crown girdle line. Clickwith the left mouse buttonand click the Use to Cutbutton. Enter an angle of 28 and an index of 96, click theApply button, and GemCadwill cut the 8 crown 's Guide: GemCad for Windows7 Now we are ready to cut thestar facets. Move the mousepointer as shown by the redcircle at the tip of the breakfacets along the edge at the6 index position.

9 Click withthe left mouse button andclick the Use to Cut an angle of 16 and anindex of 6, click the Applybutton and GemCad will cutthe 8 star the mouse pointer asshown in the figure at theright. You should see a redcircle o around the meetpoint. Click the left mousebutton and click the Use toCut button. Enter an angle of0 and click the Applybutton. GemCad will cut thetable facet. This completesthe 's Guide: GemCad for Windows8 The next step is to name(label) the facets. Move thecursor as shown at the should be a little reddot on the outline of thestone, not a red x. If not,move the mouse away fromthe edge slightly. Click theleft mouse button, and theFacet dialog will pop up. (Ifyou instead get the Edgedialog, click Cancel and tryagain.) Click in the edit boxlabeled Name and type in the Apply button, andGemCad will label the girdlefacet with an arrow and G asshown in the next move the mouse pointerinside the facet labeled 1 atthe right.

10 GemCad willhighlight the facet in with the left mousebutton, click in the Name boxand type in 1 and click theApply button. You will see athe 1 label appear inside thefacet. Continue clicking in thefacets, one at a time, andnaming them, as shown atthe right. You will notice thatthe facet names also appearin the Name column of thecutting instructions at concludes the roundbrilliant. You can save thedesign with the File/Savemenu command. Take a lookat the diagram with theEdit/Print 's Guide: GemCad for Windows9 After practicing this tutorial a couple of times, try cutting the design from the faceting diagram abovewithout referring to this tutorial. If you can do this then you are ready to try proof cutting is a summary of what we have learned:You can resize GemCad 's window panes by dragging the bars that divide the panes. GemCad simulates a faceting machine.