$150 Laser Cutter

[jhitesma]

That's one of the ones I've been eyeing I'm very curious to see how it works out for you, I'm also curious just how much it weighs since my current setup is very limited in how much weight it can handle!

The only tests I've seen of cutting foamboard is the jtech one you posted which was with a 445nm at 1w. But as we already know the 445's aren't as efficient because they don't focus as tight. Since a 200mw 405 can outperform a 700mw 445, and the 1w 445 was able to partly cut the foamboard...I'm cautiously optimistic that the 500mw 405 might have a chance.

If not...it looks like it should have no issues with balsa...and I do enjoy balsa building as well

I will say I'm glad I'm starting small on mine. Being able to work on it at my cramped computer desk is nice Even with just 1.5" of motion it's hard to keep things straight and aligned so there's no binding...and that's with the rails already fixed for me in these drive motion platforms!

 

[ScottyWarpNine]

Oops, I meant to post my sketch yesterday but I guess I didn't format it correctly. Anyway, here it is:

Like I said earlier, one sheet of MDF. Two linear track rods per axis, one lead screw per axis.
And I wanted to show the bottom of mt Reprap.

I will be building the cutter very similarly to that. I will be using 3D printed linear bushings rather than linear bearings. I tried linear bearings on the Reprap but they were very annoying believe it or not. The "Schk Schk Schk" sound they make on the rail is quite noisy. I know many other Reprap builders have chosen printed bushings for the same reason, not to mention the fact that they only a few cents of plastic. They are the same dimensions as linear bearings so they can be substituted if desired. I would like this whole design to be flexible like that so that different diameters of rod and types and bearing and lead screw substitutions can be made based on what is available and what degree of precision you're after.

 

[RAM]

this method might keep the costs down , looks like a dtfb power pod design for cnc tables
http://monograph.io/james/m-mtm

 

[Ocean]

I've always wanted someway to cut the ft designs without needing to print out plans... I'm very interested to see if that laser will be enough for foam board or darker depron. I was thinking of using a V Slot for the rails and use belts instead of linear rails and make it big enough for a 1200x600mm depron sheet.

Does GRBL come ready out the box for laser cutters or are you going to modify the code?

 

[ScottyWarpNine]

No it sure yet. I imagine it would be similar to 3D printer code that runs on arduino, or even MultiWii for that matter. There is probably a configuration file with things to comment/u comment and values to change. I haven't messed with it yet though

 

[ScottyWarpNine]

My original idea has taken a bit of a turn that can be best displayed by this video that I found. They call it an H-Bot. It is a method of XY linear motion that uses 2 stepper motors on a single, flat plane. The way I look at it, it solves every issue that I have been trying to work around.
I'm going to look further into using this method because it is super simple, much more compact than my original design, and much easier to build. Rather than cutting out several MDF parts to form a gantry system, it is small and light enough to built entirely on smooth rods and small 3D printed parts. I need to find out if somebody has implemented it using GRBL. I'm sure it's been done.
I'm super excited about this, if you can't tell. This could make the finished product much smaller and lighter than what I originally thought.

 

[ScottyWarpNine]

And here is another post because I have more to add and for some reason it won't let me edit my post.

I found an implementation of this same idea that uses 2 steppers running as if it were a typical XY coordinate plane.
View attachment 46100
Belts are necesary for both of these methods. That eliminates the cost of leadscrews, but belts and pulleys are also sort of expensive. I'll explore the possibility of using high strength fishing line as suggested earlier in this thread. I believe Spectra line is what is typically used on 3D printers.

 

[Basscor]

The issue with fishing/kite line is slipping/backlash issues on the stepper motor attachment. There are ways around this, but this is why there are very few printers that use that method for motion.

Following this thread with interest, as I have been thinking of the same thing for about a year now. Just too many other projects haha

 

[Balu]

For more information on the H-bot mechanics, I suggest to have a look at http://corexy.com

Because the real name for these is "Core XY"

 

[ScottyWarpNine]

Thanks for the link. I'm going to move forward with the CoreXY method because it will cut the amount of MDF required down to about half of what it would take to build a whole gantry to support the second axis.

The only parts of the gantry are the linear rods themselves, which will reduce the weight of the carriages, and the whole machine, significantly.

Some parts have started to come in. I have the Arduino, the two steppers and drivers, and some flex couplings which are now not needed due to the change in mechanism.

Stay tuned.

 

[Tritium]

I CAN tell you a 3 Watt 808 (ir) will NOT cut foam board well at all.

Thurmond

 

[ScottyWarpNine]

I CAN tell you a 3 Watt 808 (ir) will NOT cut foam board well at all.

Thurmond

Then I won't use an 808

 

[mjcp]

Getting excited about this project now...

Just went to a client's site for work (I'm an IT nerd) and he runs a metal work/engineering shop and is into RC cars... Well, it would have been rude not to talk CNC for RC! Short story long: He's up for helping out on the machining of the frame etc.

mjcp

 

[ScottyWarpNine]

Look what showed up today!

Initial tests are giving mixed results, but I haven't done anything too scientific yet. I need to play around with focusing more and I'd like to measure how much current the laser is drawing so I can determine what the actual power is. I would also like to try it on black foam board.

 

[nerdnic]

So is it able to cut the foam at all?

 

[Raptortech]

One thing I considered a while back when I was looking into building something to cut foamboard was a tiny drill bit. If you spin it at ridiculously high RPM (like with a high kv brushless motor), it should cut foam very well. A 1/64" that only has to cut through 3/16" of foam and paper isn't going to snap, but it's so narrow it won't affect the parts at all. Could be a much cheaper option than a laser cutter!

 

[RAM]

Sorry if this was posted already but here is a site with some settings for different materials
https://256.makerslocal.org/wiki/40_Watt_Laser_Cutter

Is has recommended settings for foam board with and without paper

 

[ScottyWarpNine]

So is it able to cut the foam at all?

Sort of. It cuts through the paper pretty quick but it barely cuts the foam. I would like to try black foam board to see if it works any better. I would gladly start using the black boards if it means I can laser cut it.

It cuts painted foam board faster than the white.

RAM, I skimmed through that but I don't think that information applies to Laser diodes, which operate at a different wavelength than CO2 lasers. If I had a CO2 laser, it seems things would be much easier.

 

[jhitesma]

Doubt black foam board would make any difference sine the foam itself is still white.

Are you able to get any cutting action in the foam? Could it be that it will take several passes at different focuses to get any decent penetration?

Curious to hear how the laser does on other materials like balsa, various papers, craft foam and such. Even if it can't get DTFB I'm still interested in this laser for my setup to use on balsa if it can handle that

 

[RichB]

My geek drive is spinning and I'm really hoping I can shut it down before the wheels start gaining traction. . . but I can't seem to stop watching videos and reading about this...