Design Resources

Design Resources

The original control system of the F1 / WoodWorker mill constrained the user to 2.5D work and short NC code files. WELmill overcomes these and many other limitations. Given the working envelope of the machines, there do not seem to be any limits on what can be machined, particularly if you are using one of the wonderful CADCAM programs which generate tool paths and CNC code for you. Model engineers will have much they can get on with but others, especially teachers and pupils in schools and colleges, may be stuck for ideas.

2.5D Software
AlphaCAM from Licom Systems Ltd, is expensive but there is special pricing for educational establishments. AlphaCAM is powerful and easy to use. Along with being a design tool it can also generate CNC code for turning as well as 2.5D milling. 3D designs can be created in AlphaCAM and it can import 3D solid models in various formats so that 3D tool paths can be set. WELsoft are very familiar with AlphaCAM and a post processor is supplied with WELmill in the folder \WELmill\Allsorts. See www.licom.co.uk

EdgeCAM from PathTrace, is another design tool which can also generate CNC code for turning and milling. It can create solid models and import, without data translation, solid models from major solid modelling software . Post processors will be available for both WELmill and WELturn in the near future. See www.edgecam.com

Design Tools - 2D Design from TechSoft UK Ltd, price Ł195. This software was designed for use in schools and is a combined drawing, CAD and CAM package. It is primarily intended to create code for Roland engraving and milling machines. WELmill cannot, at the moment (May 2003), read this code but will be able to later in the year and a WELmill upgrade will be issued. For the time being 2D Design Tools may be used just as a CAD package. Files saved in DXF format can be imported into AlphaCAM for toolpath setting and machining code generation. See www.techsoftuk.co.uk

Other software
includes MasterCAM and CAPSmill. Details of these programs can be found on the internet.

3D software
AlphaCAM and EdgeCAM - see above.

Inventor 6 from AutoDesk: a student version is available for around Ł120. Essentially solid modelling software, it can export files in STL format which can be imported by DeskProto, MiniCAM and MillWizard for tool path setting and code generation for WELmill. Alternatively, files can be exported in IGES format and imported by AlphaCAM for toolpath creation. See www.autodesk.co.uk

Pro/DESKTOP from PTC, is available to all UK schools and colleges and also to any school outside North America under a scheme co-ordinated by the Design and Technology Association, DATA. Schools in North America need to contact PTC HQ in the USA. Other schools outside the UK should contact Fay@data.org.uk for details. See www.cadinschools.org

Essentially solid modelling software, proDeskTop can export files in STL format which can be imported by DeskProto, MiniCAM or MillWizard for tool path setting and code generation for WELmill. Alternatively, files can be exported in IGES format and imported by AlphaCAM for toolpath creation. See www.ptc.com/ and www.cadinschools.org and, in www.data.org.uk ,see the CAD/CAM initiative item.

Rhino is available from various suppliers including Softcover International Ltd. While WELsoft only have slight experience of the demo version of this software, it is well regarded 3D modelling software with good support. It can export files in STL format which can be imported by DeskProto, MiniCAM or MillWizard for tool path setting and code generation for WELmill. See www.softcover.com

IronCAD, in our experience, is very much easier and quicker to use than ProDeskTop and Inventor: we recommend that you take a look at it. It takes a radically different approach to 3D modelling as compared with these and other standard programs and has some unique tools which make image manipulation very easy. It is available to educational establishments for a low nominal fee which covers shipping and administration. A trial version of IronCAD is available on CD-ROM and is fully operational for 60 days. The "Getting Started Guide" is very good and there is a large number of "Show me how" video clips. It is available in the UK from Leonardo Computer Systems, Science and Technology Centre, University of Reading, Reading, RG6 6BZ. Telephone 0118 926 9400. Full details are on UNCONVERTED WINHELP MACRO:! ExecFile("www.leonardo-cad.co.uk")www.leonardo-cad.co.uk

3D Engrave is available, free of charge, and can be found on the TechSoft product information CD-ROM. See www.techsoftuk.co.uk It is a very easy to use art-orientated package primarily intended to generate code for Roland milling machines. However, designs can be exported in STL format and imported by DeskProto, MiniCAM or MillWizard for tool path setting and code generation for WELmill. It is simple to use, works very well and is an easy entry into 3D design and manufacture. Because it is free of charge, 3D Engrave is often overlooked. That is a pity!

ArtCAM is available from Delcam and is an expensive and very powerful art-orientated package. A special version is available free of charge to UK secondary schools. It comes with MiniCAM, a tool setting and code creation utility which can be configured, with files supplied with WELmill, to create code for WELmill. See www.delcam.com

Knots: Have a look at Steve Abbott's Computer Drawn Celtic Knotwork web site and download his free program which allows you to draw knots in 2D and 3D. It can be used to create pleasing decorative designs on products. If you have installed WELmill, you only need to download the program files and not the full install version (see the instructions on the web site). A knot designed in 2D can be displayed in 3D and saved in various 3D file formats such as DXF and STL: try both formats. These files can be imported into DeskProto, MiniCAM/MillWizard or AlphaCAM for tool path generation. The result can be some pleasing 3D ornamental forms, as shown below:

The knot files can also be saved in a 2D DXF format. A file can be imported into code producing software, such as AlphaCAM, where toolpaths for an engraving tool can be set. Alternatively, designs can be pierced through thin material or a groove cut in wood which can then be inlaid with wood of a different colour. The picture below shows a 2D engraved version of the 3D knot above.

Note 1: when importing the 2D dxf file into AlphaCAM, tick the box next to "Ignore Width of Polylines". If you do not do this, the geometry will be displayed as double lines. Single lines are what is required.

Note 2: the 2D knot design is made from a large number of very small straight lines. As soon as the knot design is imported into AlphaCAM, select the whole of the design and then click the Join button. This turns the individual line segments into a continuous lines.

Toolpaths can be set from the design just as it is. However, in AlphaCAM, it is possible to convert the straight lines to arcs and thus improve the quality of the machined product. The process is in two parts:

First, turn the line segments into splines: click GEOMETRY - SPLINES - CREATE SPLINE (tick the Delete Original box) and click on every one of the green lines of the knot geometry. The lines turn brown. (If desired, the profile of the splines can be changed: use Geometry - Splines - Edit Spline then click on a spline and drag one of its control points. Take care: this is likely to spoil the symmetry of the design.)

Second, turn the splines into arcs and lines: click GEOMETRY - SPLINES - CONVERT SPLINE TO LINES/ARCS (tick the Delete Original box) and select all of the brown spline lines. Now scale the design to the required size and set toolpaths.

See www.abbott.demon.co.uk/knots.html

Celtic Knots Designer: although not its primary purpose, this is another program which can create patterns for engraving. Create a line drawing. Do not colour it. Save it as a bmp file. Use software to create a vector image of the bmp outline. Set tool paths for a pointed engraving tool. Machine.

Celtic Knot Designer costs $28 and there is a working demo version on www.celticdesigner.com

ProScribe
This software comprises a good range of fonts and utilities for Celtic artwork. It is available from Creative Technology (MicroDesign) Ltd for Ł31. It offers possibilities, not just in resistant materials, but in textiles and artwork. If you want to understand Celtic artwork and create designs from scratch then see the companion book by Andy Sloss "How to Draw Celtic Knotwork - A Practical Handbook" (ISBN 1-86019-859-7) See www.proscribe.co.uk

Mazes
Have a look at the maze maker which is available on the "Here and Above" web site. A maze can be saved as a bmp (raster) file and then converted, by other software, into a vector graphic. (To save the maze, right mouse click on the maze and choose "Save Picture As". Select the bmp file format.) From the vector graphic, toolpaths can be created. The maze pattern could be cut by a fine point engraving tool as a decorative design on a surface. Alternatively, the maze could be turned into a game and cut as deep grooves along which a ball bearing can run. www.hereandabove.com

Logos
The English version of a Russian web site has digitised logos of hundreds of well-known companies. The files can be downloaded. They are in Adobe Illustrator format. This format can be read by other software such as CorelDRAW which can then export the files in DXF format. AlphaCAM users can import these DXF files (make sure you check "Ignore Width of Polylines"), set tool paths, create code and then machine a copy of the logo. It is quite likely that other code-generating software can do the same. Be careful about the use you make of these logos as you might step into a legal minefield. www.logotypes.ru

CD-ROMs
Resources the Resources CD-ROM is aimed at schools but may be of interest to others It is available free of charge direct from Boxford Ltd.

Denford CAD/CAM Achiever The Denford CAD/CAM Achiever CD-ROM costs Ł5 and is available from DATA: see www.data.org.uk

Books
If you want patterns for decorative engraving, take a look at books on glass painting, for example:
The Complete Guide to Glass Painting by Alan Gear and Barry Freestone ISBN1-85585-950-5
Glass Painter's Motif Library by Alan Gear and Barry Freestone ISBN1-85585-871-1

You can scan the images in these books, convert them from bit maps to vector graphics, import them into CADCAM software and then set tool paths and create CNC code (see below: Raster to Vector Conversion). In addition, there are many design library CD-ROMs with material which might be used.

Have a look at titles like these:
Making Mechanical Marvels in Wood by Raymond Levy ISBN 0-8069-7358-7
Whirligigs & Weathervanes by David Schoonmaker and Bruce Woods ISBN 0-8069-8365-5
Making Moving Wooden Toys by Anthony and Judy Peduzzi ISBN 0-7153-0009-1
Working Wooden Toys by Marion Millett ISBN 0-7137-1688-6
How to Make Animated Toys by David Wakefield ISBN 0-943822-94-7

Note on Raster to Vector Conversion
A black and white line drawing can be scanned and saved as a bit map (raster) file. However, toolpaths cannot be set to a bit map image. The file must be converted to a vector graphic and then imported into code generating software, such as AlphaCAM, for toolpath setting. The results of raster to vector conversion can be very good provided that the drawing which is scanned has sharp, black lines on a clean white background. If the original is not like this, the scanned image must be cleamed and improved before conversion is attempted: see the Note below.

AlphaCAM has a raster to vector conversion utility which works very well. It can be found in the Utils - Add-ins menu. It is a free-of-charge add-in for education users: other users are allowed a number of free uses but then have to buy further use from Licom Systems. The purchase can be made via the internet from the Licom web site.

To use the AlphaCAM raster to vestor conversion utility to process a bmp file, click on FILE - Convert Raster to Vectors. Try the following settings: set Tolerance to 1, tick Recognise Arcs, tick Centreline. When the image is on the screen as geometry, click Join and select the whole design. Scale the design to the required size. You may well need to edit some lumpy parts of the design before setting tool paths

Users of other code generating software might like to look at Scan2CAD, available in several versions from SoftCover www.softcover.com, or Adobe Streamline (demo available on the Adobe web site). Vector graphic images can be exported by these programs in DXF format and imported into code generating software. Other graphics programs, such as CorelDRAW, have raster to vector (tracing) utilities which can be used in the same way.

Note on Scanning Line Drawings for Raster to Vector Conversion
Scan a line drawing using a scanner's 1 bit or 2 colour or line art setting. This ensures the drawing is scanned as black and white (2 colours) and not as grey scale or colours.

A scanner resolution of 200 to 300 dpi is optimal for most drawings. If the drawing is small or contains a lot of small detail, try scanning at a higher resolution. The aim is a scanned image with lines 2 to 3 pixels thick.

Ensure that the scanner's contrast settings are set so that faint parts of the image are scanned as solid black and are not "dithered" (full of white holes).

Do not save the scan in GIF or JPEG formats as these are colour image formats. Use .bmp or .tif format (.tif is better because it is compressed and takes up less disk space than .bmp).

If an image has been saved in a colour format and cannot be rescanned, whiten the image background before attempting vector conversion. This may require manual whitening of the background a section at a time. However, a one hit solution may work: in image manipulation software, such as Paint Shop Pro, there is a Colours - Decrease Colour Depth - 2 Colours (1 Bit) option.

Note on Machining Grey Scale Images
AlphaCAM has an Input Image as Height Map option. It can be found under the File menu provided the option has first been activated in the Utils - Add-ins menu. The original image can be grey scale or colour and in .bmp or .tif format. The user can decide, for example that white is at a height of zero and black is at a depth of 2mm. Each of the intermediate shades of grey is automatically given a depth proportional to its greyness. Toolpaths can then be set. The depth of cut is automatically proportional to the grey scale. A negative, or positive, relief image is machined.

ArtCAM has a similar capability The ArtCAM image is imported into MiniCAM for toolpath setting.

The original .bmp or .tif image may require careful preparation in software such as Paint Shop Pro before it can be used as a master for height map machining.

Your Software Finds
Please let us know about software which you find to be good, reliable, affordable and easy to use.

Code-generating Software