Messages

7731

General Mach Discussion / Re: How to control the water coolant by mach3?

« on: November 17, 2010, 02:16:05 AM »

Thosj,

http://shop.ebay.co.uk/i.html?_nkw=solid+state+relay&_sacat=0&_dmpt=UK_BOI_Industrial_Automation_Control_ET&_odkw=&_osacat=42899&_trksid=p3286.c0.m270.l1313

Without going into too much detail, SSR's switch the load at the zero crossing point of the mains ac waveform and this eliminates the voltage spike often associated with mechanical relays. Less noise = happier machine.

Tweakie.

7732

Show"N"Tell ( What you have made with your CNC machine.) / Re: Very small parts, smallest possible engravings.

« on: November 17, 2010, 02:07:35 AM »

Come on Rich, there is only eight there and you know I need sixteen. 

Tweakie.

7733

General Mach Discussion / Re: How to control the water coolant by mach3?

« on: November 16, 2010, 02:58:36 AM »

Mongkol,

I have found that SSR's similar to this one are cheap and easy to use.

Tweakie.

7734

Show"N"Tell ( What you have made with your CNC machine.) / Re: Very small parts of another kind

« on: November 15, 2010, 12:06:32 PM »

Thanks for all the information Mike.

I had always thought of DeskCNC as working with it's own  proprietary controller rather than a creation tool for GCode to use with Mach.
I can see the need for an accurate and rigid machine construction for this small stuff. 
Keep up the excellent work and of course keep posting the pictures.

Tweakie.

7735

Show"N"Tell ( What you have made with your CNC machine.) / Re: Very small parts, smallest possible engravings.

« on: November 15, 2010, 11:44:52 AM »

Hi Glad,

I can't engrave brass, to be able to do it would cost mega bucks I am afraid. 
Small CO2 lasers, like mine, see all metals as being reflectors and the only chance you have is to change the appearance of a surface coating. Their saving grace is that they are extremely good with acrylics and can cut up to 10mm thickness.

Tweakie.

7736

General Mach Discussion / Re: HELP! - breakout board diagnosis help needed

« on: November 15, 2010, 08:15:10 AM »

Hi Jen,

Thought you would have tested the wires continuity and connection points but worth a try.

what i would like to know is what the BOB expects in the way of input from the parallel port. is it just a nice square 5v "wave" for "step" and the same to change "dir"?

The direction signal is either high or low and remains in it’s set state until another command tells it to change (axis move in opposite direction). The step signal is a square wave pulse which Mach allows to be altered in terms of width and active high/low.
Most BoB's require a 5 Volt peak to peak signal here and some computers, especially laptops, only output around 3.3Volts and these do cause problems.
Most PC parallel ports are more than capable of sourcing 10 mA per pin so would light your BoB leds but it is risky to over do it and possibly damage the port.

Just a thought here but have you tried Config / Ports and Pins - check the ‘Sherline ½ Pulse Mode’ box ?  this alters the pulse width and may cause different results.

Lets hope it is the BoB and that your new one solves the problem.

Tweakie.

7737

Show"N"Tell ( What you have made with your CNC machine.) / Re: Very small parts, smallest possible engravings.

« on: November 15, 2010, 06:44:19 AM »

Sorry Glad we are hijacking your thread here.

Rich,

There is an interesting abnormally with the 0.5mm x 0.5mm matrix in so far as the dot size is smaller than I can cut a hole in a piece of kapton. It would appear that as the center of the beam contains more energy if you fire it quick enough you can get a smaller dot size. Strange.
The 0.5mm x 0.5mm tests have been done on anodized ally these photos are of traffolite engraving laminate.
Here is a slightly closer shot of the previous pic.

Tweakie.

7738

General Mach Discussion / Re: HELP! - breakout board diagnosis help needed

« on: November 15, 2010, 05:23:14 AM »

Hi Jen,

At the risk of stating the obvious, are you certain that you are making the correct connections between your C35 and your stepper drivers ?.
Have you also checked that the active high / active low signal condition between Mach and your drivers is correct ?.

Tweakie.

nb. Meaning of life and purpose of life are the same thing and can't be discussed here without upsetting the moderators 

7739

Show"N"Tell ( What you have made with your CNC machine.) / Re: Very small parts, smallest possible engravings.

« on: November 15, 2010, 05:10:22 AM »

If any of you had any experience with small scale engraving please respond.

Excellent work Glad. Real neat job.

Although not really relevant to rotary engraving I am trying to produce a small checkers board. I am cheating a bit by using a laser but so far with an 8 x 8 matrix I am down to 0.5mm x 0.5mm. These were the initial tests with a 14 x 14 matrix and the smallest here is 1.25mm x 1.25mm. The problem is photographing the result, looks like I will have to invest in one of those USB microscopes 

Tweakie.

7740

Show"N"Tell ( What you have made with your CNC machine.) / Re: Very small parts of another kind

« on: November 15, 2010, 04:03:53 AM »

More than surprising Mike that is just excellent.

Which software did you use to create the raster toolpath from your image please ?

Tweakie.