Messages

6891

General Mach Discussion / Re: Mill or Router - which is best for this application?

« on: March 01, 2011, 02:01:38 AM »

No worries Dave 

I think we would all appreciate it if you use the caps lock key though.
Thanks,

Tweakie.

6892

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

« on: February 28, 2011, 12:26:57 PM »

I have received a couple of emails from others who have cut this lizard but said that the parts are too big to fit together properly and asked me how I did it.

Well…..

Eschers original drawing had just one line defining the boundary between each lizard and it’s mate and if you pick one image, convert it to dxf and then cut on the outside of the line the resulting pieces will not fit. Cutting on the centre of the line results in the clearance between one lizard and it’s mate being the diameter of the laser beam (0.05mm). Although it may well now fit (if it was drawn accurately enough in the first place) this clearance is still not enough to enable easy assembly and disassembly of the pattern so this is why I chose to cut on the inside of the line and why I cut the parts separately and not nested.

Hope this answers some questions.

Tweakie.

6893

General Mach Discussion / Re: Mill or Router - which is best for this application?

« on: February 28, 2011, 11:30:50 AM »

Jen,

You are right about wood's density. Wood's like teak and spruce have a soft growth layer sandwiched between a very hard annual ring - the laser will cut deep into the soft and not so deep into the hard but the overall average should be pretty constant.
As the depth of cut is related to both power and speed as well as the wood itself the exact depth will always be a trial and error thing but once established it will be repeatable, at least for that sample of wood.
There will be some blackening (charring) around the edges but the surface of the work can be protected with paper transfer tape (used with vinyl signs) also there are a number of  proprietary cleaners which, I understand, can work wonders.

(Incidentally, the smallest practical beam spot size is around 0.05mm diameter without resorting to beam expanders or extremely short focal length lenses).

Tweakie.

6894

General Mach Discussion / Re: Mill or Router - which is best for this application?

« on: February 28, 2011, 10:33:41 AM »

Hi Jen,

The Epilog sounds like a good choice.

Just one point to keep in mind is that organics such as shell, bone, leather etc really stink when you attack them with a laser. I am not sure about the composite 'ablam' because I have never tried it but depending on your location (if you have neighbours) you may need a HEPA filter attached to your air extraction system. They are not that expensive but still a bit of extra cost to factor into the equation.

Tweakie.

6895

Tangent Corner / Re: New here

« on: February 28, 2011, 01:57:07 AM »

The more the merrier, welcome Mark.

Tweakie.

6896

General Mach Discussion / Re: Lots of noise in system.

« on: February 27, 2011, 08:11:31 AM »

This may be what you were looking for Derek.

http://www.machsupport.com/downloads/XP_Optimization.txt

Tweakie.

6897

General Mach Discussion / Re: Loosing steps when milling slowly

« on: February 27, 2011, 07:55:26 AM »

Really, really strange.

There is obviously something wrong with your Mach3 setup or machine somewhere because this just does not make any sense. 200 step at 1/8 with 5mm pitch screws = 320 steps / mm.

Wish I knew the answer.

Tweakie.

6898

General Mach Discussion / Re: Question regarding dsp ,control boards

« on: February 27, 2011, 07:42:47 AM »

R,

Most, if not all, of the budget priced Chinese lasers operate by 'printing' from a software such as CorelDraw using a proprietary 'print driver'. Their operation is generally more in the Raster mode than in the Vector mode.
Although Mach3 has limited Raster capability it's real strength is with Vector operation and the implementation of GCode toolpaths.

Having said that I am having great success using Mach3 in Raster mode and the results with my laser are equal, if not better than those of many Chinese machines.

Tweakie.

6899

General Mach Discussion / Re: Loosing steps when milling slowly

« on: February 27, 2011, 05:52:07 AM »

Surely that would be 1/16 step then (assuming the screw is directly connected to the stepper without reduction) - very strange. Are they perhaps 400 step per rev steppers ?

Tweakie.

6900

General Mach Discussion / Re: Loosing steps when milling slowly

« on: February 27, 2011, 02:17:30 AM »

Just a thought but are you running your steppers 'full step' or are you using microstepping ?

Tweakie.