Messages

2631

General Mach Discussion / Re: Spindle speed control

« on: January 16, 2006, 04:33:45 AM »

Hi Vmax,

It is a KBLC 240D (4771B) board.  I will try the KB Electronics site again.

Graham

2632

Newfangled Solutions Mach3 Wizards / Re: Teach Wizard A Bit more

« on: January 15, 2006, 05:37:50 PM »

Hi Folks,

Why not use the machine to do the moving.
 
Put the output of the photo cell to an input pin so it triggers when it sees white.

Connect the photo cell to the spindle.

move to a start point on the template.

Then using an incremental program move in 1mm arcs until the switch changes.

Record the machine position.

Move again.

If I am talking crap please tell me and I will shut up.

Regards

Graham.

2633

General Mach Discussion / Re: Spindle speed control

« on: January 15, 2006, 05:22:57 PM »

Sorry folks, I may have been economical with the facts here.

The spindle is DC drive

The drive card is a :-

KB Electronics KBLC-240D (4771B)
Input 115/230 VAC
Output 0-90/180 VDC
Rated 6.0 ADC

I am asking the questions as the KB Elec. site seems to be off line, so this is making it very difficult to fine any data on this unit.

The only site I can find with anything like it is Chinese and I am not fluent in Chinese or Googles translated gibberish.

Thanks

Graham.

2634

General Mach Discussion / Spindle speed control

« on: January 15, 2006, 10:38:08 AM »

Hi All,

My lathe has a variable speed controller that is operated by a rotary resistor that has a value of 4K7, my question is, can I connect the wires from the speed control into the parallel port without any other resistors.

Also it has a collar round the spindle with slots in and a infra red detector with 3 wires from it, can I also use these for the pulse count.

Thanks

Graham.

2635

Newfangled Solutions Mach3 Wizards / Re: Teach Wizard A Bit more

« on: January 15, 2006, 08:56:50 AM »

Would it not be possible to connect a photo diode and do like robots do and search the line and follow it with a macro program.  you could move the x and y axis in say 1mm increments finding the line centre and recording the points.  If the drawing was drawn 5 times size and scaled after the accuracy would be quite good.

Graham

2636

General Mach Discussion / Re: Zero Return (Home Setting)

« on: January 10, 2006, 04:41:27 AM »

Hi All,

now this is what I want on my machine, accurate homing, all the full size machines I have work like this.

How about a tweek Art,

Graham.

2637

General Mach Discussion / Re: Projecting to plane?

« on: January 08, 2006, 12:35:24 PM »

Hi Keith,

Glad to be of help.

Graham.

2638

General Mach Discussion / Re: Projecting to plane?

« on: January 08, 2006, 12:08:09 PM »

This is an example of the old way we used to do things.

See picture attached.

1.  Original image centered about X and Y zero.

2.  Circles drawn at a known pitch.

3.  Pick 2 circles to work between.

4.  Remove all the bits inside inner circle and remove all outside outer circle.

5.  The bit we machine and generate Gcode for.

6.  work out the drop using trig and add this to the Z created in the Gcode.

This is not the perfect way to do it but it works well enough for most jobs.

Regards

Graham

2639

General Mach Discussion / Re: Projecting to plane?

« on: January 08, 2006, 10:50:52 AM »

Hi Keith,

the way we did it before CAM systems was to work in concentric circles from the centre of the logo/image on a flat drawing and machine one circle at a time working out the drop in Z on the sphere at that diameter, then replace all the Zs in the code with the original Z+the drop.

Hope that makes sense.

Graham

2640

General Mach Discussion / Re: Projecting to plane?

« on: January 08, 2006, 06:11:56 AM »

Hi Keith,

to do this properly you need a 5 axis machine,  if you try it on a 3 or 4 axis machine you will get overcutting as you move down the sphere.  The correct way is to keep the cutting edge at 90 degrees to the work surface at all times.  The nearest you can get with 3/4 axis is to use a lollypop shaped tool so the back edge of the tool is not cutting into the work surface.

Most CAM systems will wrap a design round a ball using surface project, to get a negative you pocket out the background.

Hope this helps

Graham Waterworth.