Richard Bunday's CNC machine.

[Bill Hudson]

Yes Richard tell us about your CNC machine.  Did you build it yourself? Looks good what I see in one picture.

Bill

[bundyrap]

Hi Bill
 
My CNC machine is based on the HobbyCNC.com plan. I thought about building it from their plans but the complete kit of bits available from Mike Beck who is listed on the HobbyCNC.com links page is a simpler way to go. The cost of getting the leadscrews and anti-backlash nuts here in Australia was unworkable so the complete kit made a lot of sense. Great bloke to work with too Mike Beck.
 
The actual table only takes a morning to put together. The electronics to drive the stepper motors that make it move are available in kit form from HobbyCNC. I got the 127oz stepper motors which are all I need for model type use. A little electronic know-how helps putting the driver and power supply together but there is fantastic Yahoo forum for HobbyCNC users which solves most problems. Complete boards are also available apparently.
 
This driver board plugs into the printer port of your computer. It must be the old LPT1 style port and not USB and laptops are a bit of problem as well.
 
You then need software to make it all work and this was the part that I took some time getting my head around. It can be done with free software but a few dollars spent for the better gear I found was well worth it.
 
Briefly the process is to scan the piece you want to cut out or draw it on any drawing type program. The scanned image will be a raster image made up of little dots which must be converted into a vector file which is  a file made up of equations describing how the image is drawn. I use a program called RasterVect for this. All the software I use is available as downloads from the internet.
 
This vector file is then taken into AutoCad although there are other vector drawing programs available some for free. Parts can be drawn directly in AutoCad which is the main way I work. AutoCad works in real world scale - in my case millimetres, scales and generally refines your part ready for cutting. From here I take it to SheetCam.
 
SheetCam allows you to position your piece for the best cut, calculates the offset to allow for the diameter of the cutter bit ( check out Think and Tinker for cutter bits of all types - excellent people to deal with) you are using , allow you enter depth of cuts, sequence of cuts and a whole lot of other things I haven't needed yet. It spits out a thing called G code which are actual instructions telling the router steeper motors how to move.
 
The final piece of software need is Mach3. This very clever bit of gear takes the G code, makes sense of it, works with Windows XP to take control of the printer port and sends out the correct instructions to the stepper motors as well as sensing limit and home switches from the cutter table.
 
After 30 odd years swinging the hobby knife and fret saw, this CNC thing is absolutely the best thing. It allows accuracy and speed of construction I could only dream of. There is a learning curve getting into it but there is also plenty of help available and the rewards of perservering are enormous.
 
Hope this is some help
 
Richard

[Bill Hudson]

Richard, great report on your CNC.  Of course you lost me some where near the third paragraph.   About time for this old man to step forward into the 21st century.   Sounds really promising.  With the loosing of the feelings in my hands I am going to have to learn some thing like this to survive as a modeler.  

We have a member of our Model engineering club who is starting to produce  a line of little CNC machines (but smaller in scale) similar to yours.  

Thank you for taking the time to share the information with Puddleducks.

Bill

[jock]

What sort of dollars(AU) are we looking for this sort of setup, I've done a fair bit of CNC work but thatwas when I worked for TAFE and had access to the CNC workshop.
Jock

[steamboatmodel]

The BIG problem with CNC is that once you get use to having it you don't want to do without it. Unfortunately when I had access to CNC equipment we never had a spare moment that I could use it for model work.
Regards,
Gerald