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Adam Munich

Fri Jul 30 2010, 08:47PM

Registered Member #2893 Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2242

A 30W diode bar goes for $199 on ebay. 5 gold CO2 mirrors plus an expanding and contracting lens exceed the price.

Don't forget you would still need precision to align those mirrors. I'm talking microns. This means no wood, CNC'd hard aluminum "sliders" and stainless steel bars only, or you will never get very decent cuts.
However 808nm diode bars won't cut clear or white materials. It's a double edged sword, and it all depends on how much money and time you want to spend...

Problems I see...

1280522828 2893 FT93514 New Bitmap Image

1280522828 2893 FT93514 New Bitmap Image 2

Conundrum

Sat Jul 31 2010, 08:32AM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4061

i couldn't get my easydriver to step- triple checked the datasheet but nothing worked even in 1/4 step mode.
any ideas? sent the broken one to a friend for "analysis" but haven't heard anything back.

Also, many of the 5 wire motors can be driven from this driver by connecting the 5th wire to Vdd.
Make sure you monitor the current as the pot is "backwards" i.e. maximum current on the dial is actually minimum.

Lethal Shot

Sat Jul 31 2010, 12:25PM

Registered Member #1623 Joined: Tue Aug 05 2008, 03:31PM
Location: The Netherlands
Posts: 39

First which version of easydriver are you using?
What have you tried so far?
When you disconnect the motor do you see the expected voltages on the connector pins?
Does your motor still work? (batterij test)
Does the motor make noise when you connect it? If it does but doesn't move make sure you've connected all motorwires correct.
If everything above is good how does the voltage behave on the coils of the motor? You should be seeing sharkfin like voltages.
Hope this helps.

Adam Munich

Sat Jul 31 2010, 04:42PM

Registered Member #2893 Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2242

If you disconnect the motor while it's hooked up to the power source you kill the driver...

Killa-X

Sat Jul 31 2010, 11:00PM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

Yup...All you need for driving it is Power (+24v and gnd) for me, and you only have to use one of the 3 grounds on the board (said sparkfun). Then supply a step/direction signal, and connect the motor...My was 4 wire, so simply done.

But yes, If you disconnect the motor the driver will die.

As for the CO2 laser, since the thing is 40 inches long about, mounting it directly on top wouldn't be possible, yet it would make life easy. So I would still need a way to have the CO2 laser lay on the desk and manage getting the beam to the cutting head...

As said, I'm starting with a 1W blue for now, CO2 maybe a year later so I have time to adjust the CNC machine, and plan for how I'll do the laser. I've been offered around $150-$200 for the laser it self.

Adam Munich

Sun Aug 01 2010, 04:05AM

Registered Member #2893 Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2242

Instead of a wimpy 1W engraver. Go for this. You can't beat the price, and it looks to be a 10-15w diode bar. It isn't actually fibre coupled, but it is very easy to couple one. All you need is a cylinder lens to focus it into a point to feed it into the fibre. You could also just side pump the fibre, but you'll need to craft a reflector.

10eg0ld

[Edit: 400 pixels]

Killa-X

Sun Aug 01 2010, 05:40AM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

Yes however, the 1W I was going to mount directly on the head of the engraver. At least with my 1W, I can burn reds, blacks, whites, etc. Things like electrical tape slice very quickly, leaving nothing but a massive amount of smoke. The burning rates of these are fun.

The ebay laser, doesnt state its wavelength. If it's IR, it wont work with white without black dots.

As for the project, I had plans to go to get the metal today, but I was called in for work, so sometime this week I'll have to get it. For now, I plan to get a peice of plywood, and mount aluminum frame to it, using the plywood as a base former. The aluminum I will be using is corner type, with roughly 1.5" legs...Pictures will be added when I get the metal!

...

Sun Aug 01 2010, 06:16AM

Registered Member #56 Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445

To all suggesting using 800nm diode arrays, I would strongly recommend you avoid them. Fiber coupling the bar is non trivia, and even if you do get it coupled into a fiber (or buy a FAP module that is already fiber coupled) you cannot focus to a spot smaller than ~0.5mm diameter--which is much to large for laser engraving. The diode bars really can only be used for heating/welding applications, for precise cutting you want to stick with a CO2 or single emitter laser (like the 445nm ones), or a yag if you can afford it.

Killa-X

Sun Aug 01 2010, 06:55AM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

Well, The use of my 1W 445nm would be for simply engraving decales (black burns) onto wood...plastics...etc, or cutting thin materials like paper-thin vinyl, which cuts prity fast with these lasers. They can do CD cases, but that would just be super slow!

My main concerns now is design. MANY ways to do CNC machines.
You can have X axis stationary, and move a table, and have a moving Y axis that moves the laser to the position...

Or you can have the table stationary, and move both X and Y.

Both systems are rather simple, but with one stepper, planning on using threaded rod, If I have a stationary table, I would have to turn threads on both sides. A scanner for example has a belt on one side, and the other side moves along a track. I feel with a larger CNC, this can work, but it might need dual-belts. Other wise, I might just have the table move forward/back, and have the Y axiz move around.

This was my first very-basic idea.
http://killa-x.uuuq.com/model.jpg

But now that I think of it, not sure what way I'll go :)

I see a lot of people use the moving table method, having one stepper drive a thread that moves the table, and the Y axis moves the engraver.

Adam Munich

Sun Aug 01 2010, 07:09AM

Registered Member #2893 Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2242

For engraving, I'd use the "Etch-A-Sketch" model.

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