Messages

2891

General Mach Discussion / Re: New people welcome !! Come in here and introduce your self!

« on: April 01, 2015, 12:27:56 PM »

Hi Mark,

Welcome to the forum.
As a luther, this should make you smile http://www.machsupport.com/forum/index.php/topic,28721.0.html

Tweakie.

2892

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: April 01, 2015, 11:46:47 AM »

Thanks for the encouragement guys, it is much appreciated.

If only I knew the secrets of shaped glass cutting it would all have been a lot easier insofar as selecting the correct toolpath for the job. In my ignorance I just used a standard toolpath (as shown in the top of the picture) and although the glass cracked, with that layout it is not going to come apart any time soon. Brute force (more power) worked but it is not really the right way to go about it.

To cool the glass I used cold air (passed through half a dozen turns of tubing submersed in an ice bucket) with the glass resting on a milling machine parallel which had previously been placed in the deep freeze for a few hours.

There has to be a better way – it’s just a matter of dreaming it up.

Tweakie.

2893

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: April 01, 2015, 08:35:28 AM »

A bit of experimentation here…

It is not possible to cut soda-lime glass with a CO2 laser but, some while back, I read a couple of patents which cover a ‘fracture technique’ where the laser is used to heat the glass (causing compressive stress) and then the glass is cooled (causing tensile stress) which in turn creates a fracture along the defined toolpath.
Obviously I have much to learn here but needing 2 x 20mm diameter, opaque glass, discs I thought this process may be worth a try.
I found that straight line fractures are relatively easy to achieve but circular fractures needed a bit more thought.
On my first attempt I found it impossible to remove the discs so using slightly more power on the second run I created radial fractures in all directions and I now have the two required discs which fit the intended application perfectly. The edge quality is not that good (but that is unimportant for my application) although I think refining the technique will lead to better quality results.

Just thought I would share the info for any others that may be interested in experimenting with laser glass cutting.

Tweakie.

2894

General Mach Discussion / Re: Homing problem - Slave Axis stopped responding

« on: March 31, 2015, 01:47:44 AM »

Hi Plan_B,

Thanks for reporting back on the solution to the problem - this will no doubt help others who find themselves with a similar issue.

Tweakie.

2895

Show"N"Tell ( What you have made with your CNC machine.) / Re: 1/5th Scale V8 Blown

« on: March 30, 2015, 07:17:28 AM »

Words just cannot describe the wonderful work you produce Steve. As Scott has said:- WOW !!

Tweakie.

2896

General Mach Discussion / Re: program skipping commands (not steps)

« on: March 28, 2015, 11:55:57 AM »

Just out of curiosity, is your Gcode program longer than 500 lines of code ??

Tweakie.

2897

General Mach Discussion / Re: CO2 Laser and also Mach4 questions

« on: March 28, 2015, 02:33:58 AM »

No reason you could not do that but I think it would be far easier to use Terry's wrapper wizard  http://www.machsupport.com/forum/index.php/topic,23216.0.html  This works brilliantly and is just so easy to use.

Tweakie.

EDIT OOps, sorry just realised you will be using the Chinese software rather than Gcode so yes, as long as the rotary axis is calibrated to produce the same linear dimension on the curved surface as the plane axis it will be replacing then it should work really well.

2898

Tangent Corner / Re: Another cool 3D printer

« on: March 27, 2015, 04:45:33 AM »

That certainly is true innovation thanks for sharing.

Tweakie.

2899

General Mach Discussion / Re: CO2 Laser and also Mach4 questions

« on: March 27, 2015, 04:22:20 AM »

As you are aware, commercial laser machines (at least in our price range) do not run Gcode as standard (the FSE lasers may be an exception if you are bold enough to buy from them) so you are pretty much limited to the Chinese software and CorelDraw.

If you do decide to tear out the controller in favour of Gcode then perhaps browse through this thread http://www.machsupport.com/forum/index.php/topic,12444.0.html 
(as it has become very long I suggest you scroll through looking for the images then only read those posts which may be relevant to your requirements).

As for greyscale engraving, Art has developed a plugin with Arduino for Mach4 but so far he is, I think, the only one who has got it to work at this moment in time.
Mach3 already has an engraving plugin, which I find is excellent but not everyone has found it easy to use. The mach3 pluging will only work with the parallel port so external motion controller’s are not supported at this time.

A 40Watt CO2 laser has plenty of power to work with Cermark / Thermark / etc. so no problems there (other than the cost of the compound).

Hope this answers some of your questions.

Tweakie.

2900

General Mach Discussion / Re: Stepper motor working in 1 direction only!

« on: March 26, 2015, 01:28:41 PM »

Hi, could someone help me ? i have only started cnc a few months ago and have made a controller which worked fine the stepper driver is Chinese (24V-50Vdc) actual 48Vdc.

I have now made a second but i am having some problems as below.

Steppers erratic movement and will only run one way, motor step/direction is set up as my previous driver
X - Step pin 2, dir pin 3 and so on for 3 axes.  No home/limits set, no e-stop set by unchecking the input ports and pins set up correctly as is in Mach ports & Pins settup.

My stepper drivers are Chinese which i have used before (24V-50Vdc)
The input voltage to these however is reading 24Vdc. I am wondering if this the marginal voltage is the problem.

Any help will do please, thanks

What is the maker and part number of your stepper drivers ??

Tweakie.