I located a spot on the opposite side of the Y axis and mounted a second limit switch.

Hi Bill,

There shouldn't be any reason why your home and limit switches aren't working. I have five switches (two on x-axis, two on y-axis and one on z-axis) like you do. One of the x- and y- switches doubles as a limit and a home switch. I've attached a screen shot of the set up I have in Mach3. Notice they all have the same port# and pin number, and all are active high. Let me know if there is anything else I can help with.

Best regards,
Mike

I located the switches for the X-Axis in much the same way I did for the Y axis. The only difference were that the plexiglass mounting blocks had to be longer, and it was harder to locate a spot for the switches to hit.

Because of the unique geometry of the Z axis on the Routazilla I had to come up with a special way to mount the homing switch. There was no easy place to mount the switch stationary. So I was forced to mount the switch to the moving Z axis plate. Finding a place for the switch which didn't run into the bearings or lead screw took some time.

Here is how I wired the switches. I connected the wires to all of the switches to the Normal Closed lug (NC). All the switches were connected to Pin 11 and ground of the Hobby CNC Pro board.

After hooking up all those wires, the machine was a little sloppy, soooo.... I took a trip to the local Radio Shack to gather some items to help control the cabling. I bought some flexible black tubing designed just for this. The tubing came in 10' lengths which is plany for this design. I slipped the motor wires from the Z axis into the tubing along with the limit switch wires. I was concerned that this might not be susceptible to electronic noise but this has not been the case so far. I secured the end of the cable tube using a hose clamp also from Radio Shack.

It is probably about time I told you about my machine. I built a Routezilla II from plans I got at http://www.kleinbauer.com. John Kleinbauer is one of the first people to offer plans for build it yourself CNC Projects. He currently offers 15 different plans which range from CNC mills, router, 4th axis and driver boards. All the CNC plans in John's collection cost $36 (money order or check only. US and Canada).

The Routezilla II was designed to meet peoples desire for a larger Router. The
Routezilla has a 18" X 40" bed with a 12" X 26" X 2" cutting area. The machine was designed to cut out Doll House parts, Lawn Art and other craft parts at a faster rate than John's other machines. This design is for the experienced builders only because John left several details to the builder that he normally details in his plans. I didn't find this to be a short coming for my build. John developed this project online and showed details of the completed project before he had completed the plans. Several people copied the design so John released the plans as is.......

I like many things about the Routezilla II. The only thing I wish for is more Z travel. I toyed with expanding the Z axis but after looking it over for a while, I realized that this would involve several design changes. Besides, most router bits are 2" cut length or less.

Happy New Year everyone.

Bill

I haven't gotten the homing and limit switches ironed out yet so I have disabled them.

When I press the reference Home button in Mach 3 the axis moves but doesn't necessarily hit the switches before stopping. This makes me wonder if I have some noise in the system, or if I have set something like soft limits incorrectly.

Mach 3 is such a powerfully, full featured program that it can sometimes take you a little while to figure out exactly what it is you want it to do. I'm probably due for a DUH!!!! moment soon.

I begin to wonder if perhaps I misunderstood the the description. Perhaps I need to wire the home switches in series to one pin and the limit switches in series to a different pin?

Any help would be appreciated.

I will be moving on in this description regardless.

Hi Bill,


Yes, wire all your home and limit switches in series, on one circuit. Mach3 doesn't care one iota which switch is triggered when homing or a limit is reached. One end goes into one of the inputs on the HobbyCnC board (pin 10 for example) and the other goes to ground. If you go to the Diagnostic page and watch it for a while you might see the "LED" for the pin light up even though you weren't doing anything. If so, it's likely noise tripping the limit/home switch to stop prematurely. You can handle this one of two ways: Go to the main configuration page and set the debounce number to a higher number, say 0 --> 100 (or higher) or add a small capacitor across the pins (something like a 0.01 uF cap between pins 10 and ground on the Hobby CNC board.

If it's not noise, do the steppers sound like they are missing steps? Is the problem always occuring at the same place on the axes that are being zero'd? If so, it might mean that you have some binding and will need to spend a little time getting things aligned better.

If you have soft limits set you will hear the motors "wind down" as they enter a zone around the limits setting. It is very distinctive. If you hear this then you need to set them wider/longer/higher.

Best regards,
Mike

Originally Posted by bgriggs

...I am hooking up limit switches next and then doing a brief description of my machine, followed by setting up Mach3 then moving right into Vcarve Pro, Cut3D and Photocarve.... Still a long way to go. I may break it into another thread or keep it all in one.... Haven't decided yet...Bill

Bill, this has been an excellent thread and once your problems get ironed out it will be a great diagnostic tool for others building a CNC anything. I would like to see you take this single thread to at least the first successful cuts. If you also take time to inform us a bit about software and just to let us learn what you're learning, then this thread will probably be around for quite a bit!

Thanks for keeping on!

Originally Posted by will_newton

Bill, this has been an excellent thread and once your problems get ironed out it will be a great diagnostic tool for others building a CNC anything. I would like to see you take this single thread to at least the first successful cuts. If you also take time to inform us a bit about software and just to let us learn what you're learning, then this thread will probably be around for quite a bit!

Thanks for keeping on!

I have determined through testing that the problem is in a software setting, I am getting closer to solving. The switches now work but need tweaking. I also need to read more of the manual. As soon as I get it perfect I will detail the problem, step to investigate and solution.

Thanks for the kind words.

Bill

I am going to ignore the limit switch settings for now and move on

The basic controller box has been completed and the router is up and running. So now it is time to talk about the software needed to make a CNC machine tick.

CNC machines generally need three pieces of software to get the job done.

1. A drawing program - can be a CAD package or in some cases a Drawing program like Corel Draw or Adobe Illustrator.

2. A Cam package - to generate the tool path that the cutter will follow.

3. A motor driving program - post processes the tool path to generate step and direction commands to the motors.

There are many choices for these three pieces of software. Everyone has their own favorites. In fact, several of the programs available to hobbyist can perform more than one of these functions.

For a drawing program I use an older product that is no longer available, called Drawingboard. I use this program because it draws quickly and accurately. When I need something with a complex, organic shape I use Rhino3d or Alibre Design, both of which are still available. There is nothing special about my choices so I will move on.

For a Cam package I chose VCarve Pro 4.6 from Vectric.com. I have been watching the development of this program from it's inception and can safely say it is easy to use , powerful and worth every penny. I will do an in depth discussion of VCarve Pro shortly.

I chose Mach3 for my motor driver software. Mach3 is in my opinion one of the most versatile driver packages out there. You can drive a router, mill, laser, plasma cutter, lathe, edm, foam cutter, hexapod and robots all from Mach3. I will be covering Mach3 next.

Here are links to the software mentioned.

http://vectric.com/
http://ashlar.com/
http://www.corel.com/international.html
http://www.adobe.com/products/illustrator/
http://alibre.com/
http://www.artsoftcontrols.com/artsoft/index/index.htm

Very Nice write up Bill, thanks for sharing.

Originally Posted by Dogwoodtheone

Very Nice write up Bill, thanks for sharing.

Your welcome. I haven't posted in a while because I have been under the weather..... I will pick up again soon with the setup of Mach3.


Bill