Laser CNC, engraving works, cutting doable?

[altera]

I did some more research on the 445nm diode and I found this post by jayrob. He's been kind enough to measure the dot size at 2": 2.3mm X 5.4mm. That is just to big. So it looks like I'll go with a 405nm diode.

I'd love to build a dual 405 lasers but considering the cost of a single diode build, I'll stick with that for now and maybe upgrade down the road if needed.

So here is what I think I'll be ordering:

• 405-G1 from JayRob ~$55
  
• FlexModP3 ~$36
  
• 405nm 12x sled $50
  
• Goggles $16

I have a few Aixiz hosts already here.

Plus shipping with all those guys. If anyone knows of a seller that can combine any of the items above I'll be happy to go with them

Does that look good?

 

[Helios]

I did some more research on the 445nm diode and I found this post by jayrob. He's been kind enough to measure the dot size at 2": 2.3mm X 5.4mm. That is just to big. So it looks like I'll go with a 405nm diode.

I'd love to build a dual 405 lasers but considering the cost of a single diode build, I'll stick with that for now and maybe upgrade down the road if needed.

So here is what I think I'll be ordering:

• 405-G1 from JayRob ~$55
  
• FlexModP3 ~$36
  
• 405nm 12x sled $50
  
• Goggles $16

I have a few Aixiz hosts already here.

Plus shipping with all those guys. If anyone knows of a seller that can combine any of the items above I'll be happy to go with them

Does that look good?

Thats at infinity... for burning you can focus it to a pinpoint :undecided:

 

[altera]

Thats at infinity... for burning you can focus it to a pinpoint

I'm confused. You said "If you want detail go with the 405nm" in your opinion is it possible to focus the 455 to 1mm diameter dot at 5" distance? I'd love to go with the higher power option...

 

[Helios]

I'm confused. You said "If you want detail go with the 405nm" in your opinion is it possible to focus the 455 to 1mm diameter dot at 5" distance? I'd love to go with the higher power option...

The 405nm will be "tighter" even focused but I was just saying that the 445nm can be focused much tighter than the specs you posted.

405 can be focused to a ultra tight point

445 can be focused to a very tight bar

in either case we are talking about fractions of a mm

 

[qumefox]

Though the 445 will still always focus to a line, and not a single point, regardless of the distance. If you want to get an even area with it, the best you could hope for is a square about 3x larger than the minimum focus of the single mode 405.

It really depends on how much detail is wanted.. but the 445's downfall will always be it's output isn't a TEM00 dot. In a cutter, the line output of the 445 would mean cutting some directions would lead to a thin line and motion 90 degrees off would be a wide line...

Raw power isn't everything. In pretty much every application other than laser pointers, beam specs matter as much as power does.

 

[altera]

Do you have any idea if I could get the max diameter below 1mm?

 

[qumefox]

If you mean for a 445nm, probably not unless you were dealing with less than an inch of distance between lens and target. And at that distance, you'd have an issue with smoke and debris contaminating the optics.

 

[altera]

Sounds like I should go with the 405nm then.

 

[qumefox]

If you go with a SF-BW512L 12x sled, just don't go over 700mA.. I've had a couple LED fairly quickly running at 750mA. If you really want to be safe, stick to 600-650mA.

 

[Helios]

Have you considered IR? I am no expert on these diodes as my only uses for lasers are all visual but high power can be had for quite a reasonable price! If your engraving it doesnt really matter if theres a nifty colored beam coming out.

 

[altera]

The reason I didn't want to do IR was safety. I'd rather see the beam. But if I'll investigate IR before I put in the orders.

 

[jakeGT]

and if you do go 12x and use the bdr-506j, keep it under 500mA for long life

As I think the standing plots are, that 500mA may be too much for long life, but maybe not, in any case, if you don't want to take a chance and switch diodes every month, play it safe

 

[altera]

Thanks everyone for the advise the orders are in. I'm going with the 405nm for now. I'll let you know if it works or not

 

[Cyparagon]

Do you have any idea if I could get the max diameter below 1mm?

Maybe you missed my post:

The focal point will be smaller if you bring the laser closer.

 

[altera]

I did see you post, it's hard to make an informed choice

I can bring the laser closer of course. I estimate that I'll need to have a laser dot of maximum 1mm in any direction. I don't want to bring the laser closer than 1" to the surface (optics would get the smoke from the plastic).

In that scenario can the 445nm diode with a good lens (glass 405 aixiz) stay under the 1mm max dot (even if not round)?

 

[altera]

Most of the stuff has arrived, except for the flexmod I guess DrLava is very busy at the moment. I'll have to run it off the old aixiz driver for now.

Extracting the diode was very easy on this sled, much easier compared to the LOC sleds (nerve racking). To test I built a DDL driver real quick and sure enough the pretty violet light appears, and very bright too even at 140mA. Once focused it burned paper in an instant.

Maybe I'll be able to do a test run on the CNC tonight...