CNC controller

[osdhillon]

Hi,
Everybody

I am new to this forum. I am planning to build a CNC router for my woodworking hobby. I need help in finding and selecting the right CNC Controller, driver and motors. The software I am thinking to use is "BOB CAD_CAM". I need help in how can I drive the motors from my PC. Which kind of controller should I use? Which interface card , motor driver and power supply are compatible with each other? How about some schematics?

You input is appreciated

thanks in advance

Cheers

Dhillon

[Bubba]

OSD,
Need a little more information to be really helpful. Are you running steppers or servos? Are you going to do 2 1/2D work or fullblown 3D. For the control program, do you intend to run Dos or Windows????
My personal favorite includes Turbocnc (dos based) controlling the parallel port then into an opto isolated breakout board (there are several out there) and feed this into Gecko drives (in my case 320 or 340 for the servos)
If you want a windows based controller, then I would use Mach2 again into a breakout board and again problably Geckos
This is not to say these are the only combinations, as there are many suppliers (many of whom advertise on this board) that will work perfectly well. But what you asked is kind of like saying I want to buy a truck, but we don't have a clue of what capabilities you will require.

The more information you give us, the better ideas we can give you.

[osdhillon]

Bubba

Thanks for the reply,
I am definately using windows. I have solid idea of the mechanical design and am planing to build a 3-axis CNC using servo motors as they are said to be more durable. I need more information between the PC and the servo motors; how to run and controll motors and how to index it to zero. Need info on the power supply, interface board and the drivers (How these go together).
Thanks
Cheers
Dhillon

[Bubba]

Dhillon,
Ok, now we are getting somewhere. OK you what a windows based controller. Therefore, I would look at Mach2 (www.artofcnc.ca) and I personally would look at the breakout board by Campbell Designs (www.campbelldesigns.com) as it was designed with Mach2 in mind.
These two parts are connected together through the parallel port by a standard DB25 cable. The control signals from the breakout board will be wired to the drivers and as you have indicated servos, two of the most popular are the Geckos and Xylotex.
The main power supply for the servos is generally an unregulated supply consisting of a transformer (correct voltage and amperage), a bridge rectifier, properly sized capacitor. (Again, need more details on how to size this). The output of the power supply is fed to the drivers and then to the servos. At the servo end, there will be encoders that will provide feedback to the drivers on their position.

As for the procedural questions on how to run the program (index to zero etc) I suggest you select your control program, and then download the manual on how to use it. It will seem intimidating at first, but the more you read and even sketch things out on paper, the more clear it will become.

Hope this will help you get started, and keep the questions coming. There are many here that will be willing to help out and like me, give our .02 worth.

[osdhillon]

Bubba

thanks for valuable info. I have yet to decide which servo motors to use. Any suggestions (looking at 48" travel on Y and x-axis). For Drivers (Servo, Gecko looks fine). Also need some suggestions on the encoder.
Thanks
Dhillon

[Bubba]

Dhillon,
As to servo suppliers, there are MANY (search the zone for advertizers) and many servos will include encoders already. If you need to add encoders, a popular choice will be USDigitial or Renco. If you are going to run Geckos, remember they will only supply 50ma or you will need a seperate supply for them. This means generally, you will be limited to single ended (not differential) encoders to meet the 50ma requirement.

[ger21]

You might want to look at the servos that Jeff at HomeCNC sells. They should have plenty of power for your router, and he already has the encoders installed. http://www.homecnc.info
Like Bubba says, go download the Mach2 manual and start reading. It has a lot of valuable info and should answer a lot of your questions.

[osdhillon]

Camtronics have the kit for Gecko servo drives. How about the servo motors and lead screws. Any suggestion which one to buy and from where.

Thanks
Cheers

Dhillon

[AirAce]

These forums are mind boggleelling. And it is new to me. But I would like to ask a question that may already be somewhere in one of these forums.

I have a Cincinnati Milacron Sabre 500. The control electronics and documentation is antiquated. I want to use a program similar to Mach4 or Flashcut to operate this machine. I need to know is anyone has done this. And I need to know how far I have to commit surgery on this beast. I know I can use all the same hardware, motors, screws etc. And I think I can keep the motor controllers. So again I am guessing that I need to find out the interface protocol which tells the motor controllers what to do.

I'm and electrical engineer with lots of background in electronics but I am not knowledgeable on the working guts of CNC machines. I have the schematics on this machine. So, I think that there is sameplace between the keypads and the motor controllers where I can sever it's guts and replace some of them.

I've been geting up to speed on retrofitting manual machines, so I'm guessing that this donosour is at least approximately like the new ones.

Even though this is a 92 model it is in excellent mechanical condition, and electronically for that matter. It works great but it is so painful trying to operate it in it's natural karnal state.

Any help is greatly appreciated.

I have a Tormach and like it very much.