Messages

1

General Mach Discussion / Relay for Spindle (Plasma torch on) buzzes, rattles, on off really fast

« on: April 29, 2014, 05:12:54 PM »

The breakout board we have has two relays.  Looks like the relay we use has died.  It will flick on but not flick off unless you unplug the power to the whole cnc controller box.

So I went and moved the two wire to the second relay and reassigned the pins to suit.

Now the plasma torch is firing again and turning off.  On the old relay it would fire and stay on.


I notice that when the plasma is is the relay will rattle fast as in on/off 10 times really fast until the plasma arc is established.  Maybe this was also occurring when on the first really and it just simple wore out.

So what can I do to stop this flicking of the relay?  Is there a debounce setting for an output like this relay?   Or is it just electrical noise from the plasma?

2

General Mach Discussion / Manually enter value into DRO to move machine then click "To Go"

« on: January 14, 2014, 09:36:05 PM »

I think I used to be able to enter a distance in the DRO on the "Program Run" screen then click on the  "To Go" button and then it would move to that position/distance.

It does not seem to work like this anymore, is there a setting somewhere that I can change.

I do not want to enter it via the MDI screen as it is slower to do that what used to work.

Any ideas?

3

Show"N"Tell ( What you have made with your CNC machine.) / Re: CNC seem welding????

« on: June 04, 2009, 05:57:26 PM »

Tack and clamp as much as possible.  That is sort of the cardinal rule when welding anyway.

Put it this way.  There is a machine called a "beam welding machine".  Basically it welds 3 bits of flat steel together to make them into an I beam.  This particular machine is being used for welding the chassis rails for low loader truck trailers ( to put heavy bulldozers etc on).  And on this machine they use rollers with hydraulic rams pushing and clamping it all the steel together.  Then there is a welding machine either side of the plates of steel and away it goes. 

There must be some serious clamping forces there with those hydraulics. 

But yeah, heat makes metal expand and get bigger and warping and twisting is very common.

4

Show"N"Tell ( What you have made with your CNC machine.) / Re: CNC seem welding????

« on: June 04, 2009, 08:52:43 AM »

Hey I like this topic.

I did this on a few scrap bits of steel.  Here look at these pics, pretty good for only one go at it mucking around.

Peter
http://www.learn-how-to-weld.com

5

G-Code, CAD, and CAM discussions / Re: What is a Macro? and what can it do for me?

« on: February 19, 2009, 06:28:16 AM »

Hmm,  okay I'll tell you what I'm thinking of doing and maybe you can point me in the right direction.


So imagine a 3 axis machine.  Then on the bottom/ underside of the z there is another axis a,b or c?  For tangential knife function.
Then under that is another axis a,b or c?  I don't know which axis  is which.  anyway.

The two axis underneath the z will just need to be used as, I think they call it just as "indexers"

1.  So I want to move machine to start position. 
2.  Then move tangential axis (a) (rotate to say 90deg.)
3.. Then move other axis (b) (say 90deg. as well)
  This above part is what I want maybe make into a macro or as you called it a sub program.

4.  Then when the tool is in that position move to next position.
5.  Maybe have to change angles of a and b axis to something else then move on agian etc.

So the part I want to not have to keep punching into g-code will be that a,b axis (index) tool position.
This might be like a tool change macro?

Also those a,b angle adjustments will be different.  There might be 3 or 4 diffent combitnations or,
a,b axis moves to do.

Do you understand?

Peter
Australia

6

G-Code, CAD, and CAM discussions / What is a Macro? and what can it do for me?

« on: February 17, 2009, 10:32:20 PM »

What is a Macro?  and what can it fo for me?

I'm thinking a macro is a pre saved snipped of code that is entered into the standard g code where ever you need
it so that you only type in the one line instead of heaps of lines of code every time you need to do the same command.

Is this correct?  or am I off with the fairy's?

Peter

7

General Mach Discussion / Re: Corner slow down for plasma, laseroxy fuel and waterjet cutting?

« on: September 12, 2008, 05:06:08 AM »

Yes I agree a cut should be as close to 90degrees as possible.  Yeah using a bigger powered plasma is another way around it, then you can even to an oxygen plasma and use Hi def plasma etc etc.  Anything is possible  with $$$$$$$$$$$$$.

And then if you say you cut at 500mm/min and the result is acceptable then it suits you fine.  Just the next person might not be happy with the result.  Really in my opinion after about 3/8" to 1/2" I would start to use an oxy if I was cutting that thickness and more.

What machine do you use?

8

General Mach Discussion / Re: Corner slow down for plasma, laseroxy fuel and waterjet cutting?

« on: September 12, 2008, 02:22:28 AM »

If you slow the whole g code down, technicaly you are not traveling as fast as you could along the straights.  Therefore your parts throughput per hour will be much lower.  Also the slower you go, the wider the kerf.

Still would be a nice feature to have, rather than editing every corner in gcode.

9

General Mach Discussion / Re: Corner slow down for plasma, laseroxy fuel and waterjet cutting?

« on: September 11, 2008, 05:14:27 PM »

Hi ftomazz,

You say you cut plasma.  How thick are you cutting?

Yes keeping the travel speed constant is critical.  But  this is only noticable really on the thicker steels,  ie the thicker you go the more obvious it becomes.

Plasma, abrasive waterjet, laser and oxy are all what you would call a flexable tool.  To illustrate it more clearly, imagine squeezing out some honey out of a squeeze bottle on your toast.  Now imagine you are a cutting machine, and move in the shape of a square.

You will find that when you go to each corner you will have to wait for the "lag" of the honey to catch up to that corner, yeah.  Now imagine using plasma or waterjet but you are cutting say 1" thick steel.  What will happed is the top surface of the plate will cut spot on and the square will be perfect.  But underneath on the bottom side the same corners will become radius corners because the plasma at the bootom has not yet gotton to the corner when all of a sudden the machine changes direction.  Yes the top has got there but the bottom has not.

On thin sheet steel this is not really an issue., but on thicker plate it becomes a pain in the A**.  Even when just cutting a radius, the top of the part will be accurate but the bottom will not.

So yeah, that's why you would want a "corner slowdown feature", but if you havent the need for it, don't worry about it.  It is just that I'd like to start one day making a few cutting machines and this would be a feature that I would definantly need.

Peter

10

General Mach Discussion / Re: How many axis can I slave? X and Y or just X

« on: September 04, 2008, 09:00:11 AM »

When I had my plasma I had it driven on both sides of the long axis with two geckos, slaved through mach.  So I can do it with the one axis, just don't know if I can do it with the other axis at the same time as well.