Messages

6401

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

« on: August 16, 2011, 01:26:23 AM »

Hey naPS,

That's brilliant, looks like you are really getting the hang of it. Thanks for posting the pictures (we all love pictures).

(with deep engraving of wood / plastic I use paper transfer tape [used for vinyl sign application] - this prevents the surface smoke discolouration and is easily removed after the work is completed  ).

Tweakie.

6402

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

« on: August 15, 2011, 12:01:10 PM »

Hi John,

Sounds as though you have the 'Ports and Pins' set up correctly and that the problem may be feedrate related.

The plugin's output on the digital trigger is dependant on the Kernel speed, the image pixel value and the axis feedrate - currently, the Kernel speed should be 25000Hz  and the axis feedrate set in motor tuning somewhere between 4,000 and 20,000 mm/min with the plugin feedrate set somewhere above 300 mm/min.
If your laser diode has good response then you are in with a chance but it is pretty much 'trial and error' here.

As an example, my true X Axis feedrate is 4,500 mm/min and I set the plugin feedrate to 15,000 mm/min and this just squeaks in at the bottom end of the requirements for a CO2 tube which has really poor response at the lower end of the power scale.

Experiment with the feedrates and let me know if this resolves the problem.

Tweakie.

6403

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

« on: August 15, 2011, 04:19:20 AM »

Hi Amir,

I use 5mm pitch ballscrews and my maximum, 100% reliable, G0 and laser feedrate is 4,500mm/min.

I doubt belt drive would improve my machine speed because of the mass of my combined X and Z axis but a purpose built machine could perhaps exceed 20,000mm/min without too much effort.

Tweakie.

6404

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

« on: August 15, 2011, 02:49:45 AM »

Thanks Dave. 

Hi Amir,

The image size is 90mm x 90mm with 0.15mm stepover. I don't remember the exact times but the laser took minutes (at 4500mm/min) and the magnet took hours (at 300mm/min).

I certainly like the idea of an air operated solenoid, particularly if it could be operated faster than a magnet.
Because the moment of impact lags behind the trigger event and the plugin operates in bidirectional mode, currently, any increase in feedrate beyond 300mm/min results in noticeably staggered verticals.
It's a challenge, but even a small increase in impact speed could reduce process time considerably.

Tweakie.

6405

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

« on: August 14, 2011, 08:30:44 AM »

Have you tried it yet ??

Tweakie.

6406

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

« on: August 14, 2011, 08:23:30 AM »

Hi Dave,

Andrea pioneered the magnet design which is driven from the Mach digital trigger by one phase of a bipolar stepper motor driver. The impact tip is, I think, tungsten carbide and it is ground to a very sharp point but what is perhaps most interesting is that it impacts the work on the return stroke so it is the spring pressure x travel distance (Z height) that determines the impact force and therefore the depth.

This Impact engraving is not something that will necessarily work 'straight out of the box' because my first attempts were just terrible but with the right setup the results are, I think, quite stunning.

Tweakie.

6407

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

« on: August 14, 2011, 07:59:22 AM »

Hi Dave,

It's a non-PVC engraving laminate I purchased in France with brushed aluminium look alike on the surface and black plastic beneath. (If using the impact magnet on aluminium sheet the indentations could be colour filled to obtain the same effect).

Tweakie.

6408

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

« on: August 14, 2011, 05:46:28 AM »

Relating to the Mach Impact / Laser Engraving plugin, Andrea (Robotmar) has very kindly provided me with a couple of his magnets in order to evaluate the plugin's impact engraving performance. It is a lot slower than the laser but the results are so similar that I thought you may like to see a side by side comparison with the same image produced by each method.
The first picture has been produced with the magnet and the second with the laser.
(This thread relates http://www.machsupport.com/forum/index.php/topic,16446.0.html).

Tweakie.

6409

G-Code, CAD, and CAM discussions / Re: Gcode plugin

« on: August 14, 2011, 04:35:44 AM »

Hi Croy,

The Phlatboys use Sketchup and have the plugins for GCode etc. which are free to download from their forum. Although their machine is upside-down the Z Axis direction GCode is still correct for conventional machines. http://www.phlatforum.com/viewforum.php?f=147&sid=7b90298ca9c43218b1373a5bd7bf5cb6
They are an extremely nice group of guys and only too willing to offer advice and help if requested.

Tweakie.

6410

General Mach Discussion / Re: Slaved Axis Direction

« on: August 12, 2011, 07:31:37 AM »

I was just curious because I never got this type of setup to work successfully, I suppose it depends on the manufacturing quality of the motors but they were always trying to bounce off each others indented position except for the few places where they matched perfectly. I since thought that a flex coupler may have solved the problem but changed the design before trying it.

Tweakie.