Darkly Labs Community

G-7 Lens upgrade?

Hello,

Ive been looking into the pros / cons of lenses - and the G7 looks like the happy medium for cutting.

 

Anyone used a G-7 lens and had good results?

 

Also does anyone know if the Lens Holder is 7mm or 9mm ?

 

 

Thanks :slight_smile:

Hi Josh,

We haven’t tested the G7 lens.

The Emblaser 1 lens holder size is 9mm.

Keen to hear the sort of results you get if you test it.

Thanks for that Domenic-

It comes as the lens in a threaded 9mm holder but what it the case for them called?

(the silver case with the grips for focusing) - i can’t seem to find one to buy to put it in…

 

 

We haven’t really found a common name for that part. We call it the focus ring, but that may not mean anything to a supplier.

We have lots of these rings. Where are you situated? We’d be happy to post one out to you if that helps.

Email your details to domenic@darklylabs.com

By the way, you can get away with out the focus ring. It just is a little trickier to focus and you have more changes of touching the lens.

Thanks Dom - cant fault the darkly labs support and community at all…

Ive sent my details - I dont trust myself with a bare lens!

 

also if anyone is wondering here is the info from the site regarding the lenses:

 

3-element lens (Standard lens)
3-element lens has a long focal length, low divergence beam profile but it has a very noticeable output loss since it has multi lenses.

| Advantage | Tight laser beam with the cleanest beam profile |
| Downsides  | 70% efficiency (1W diode = 700mw with it) |

G2 lens
G2 is a high pass lens which lets more laser light to pass through.
The most ideal lens for maximum power and burning.

| Advantage | 95% efficiency, small beam aperture perfect for close range burning |
| Downsides | Increase beam divergence(wider beam) and affects the beam profile  |

G7 lens
G7 is the second best high pass lens but it won’t increase the beam divergence like G2 does. G7 has a long focus length just like 3-elements lens, a well balanced lens between 3-element(divergence) and G2(power).

| Advantage  | 88% efficiency, long focal length and tight laser beam |

 

The G7 lens arrived this morning - and I have screwed it into the ‘focusing ring’ which came 2 days ago.

 

I have done a test using the original 3 element lens and taken photos.

I will now repeat this test using the G7 lens tomorrow (when the threadlock sets for the focus ring) and upload the results.

 

More to follow very soon…

Tests complete.

i have made this a fair test by focusing both lenses as accurately as possible, using the same material to cut, same conditions, same job, same speeds.

 

3 watt emblaser1 - 4mm/sec 100%power

 

3 ELEMENT LENS - CUT THROUGH AT AROUND 7 PASSES.

G7 LENS - CUT THROUGH AT 3 PASSES

 

I was shocked to see the cut fall out at 3 passes! - also as you can see the difference in the width of the laser cut line is very small - i would say tenths of a mm difference.

 

please let the following images show my results.

 

I will keep the g7 lens in now and keep trying different jobs - but  initially i am VERY impressed!

 

josh,

Thanks for posting the results of the G7 lense.

Is the 3 pass of the G7 lense (in the last pic) burnt or is it the background.

Also have you used the same lense for engraving. 

If the results are repeatable it would certainly cut down on the time to produce articles.

Has Domenic expressed any thoughts on using this G7 lense for the production machines.

John

Hi John,
It’s not burnt, that’s just the table showing through the the hole cut in the ply!

Not engraved anything yet, I’m just cutting out a very intricate pattern shape as I type and it is doing it perfectly! No burnt messy edges and it’s cutting in 2-3 passes.

Domenic has shown interest and I’m sure he will be looking at these results and may want to try it out himself!

Hi Josh, As I am still researching the why’s and wherefore’s before purchasing the Emblaser as I am totally inexerienced and your test results look very promising.

Would you be able to provide details for a reliable reseller of the G7  as I would prefer to start out with everything at its best. I am assuming you are located in Australia.

I have definitely found this site to be the most informative and helpful in making my mind up 

 

Thanks in advance

Hi Graham,
I’m afraid I’m actually in the UK.
(Yes I spend my late nights testing laser lenses haha)

This community and Domenic especially are one of the most helpful and responsive of any company I have used.

I got the G7 lens from:
https://www.sanwulasers.org/product/lenses

You need the 7mm lens and holder.

You simply unscrew the existing lens and screw this one in.

You should remove the laser unit first so you can see what you’re doing.

Take your time, don’t touch ANY lenses and take at least an hour to focus it in, test, focus, test, etc.

1 Like

Josh, how does the focus change with the G7 lens? Does the distance to the work from the fan shroud increase as the text would lead one to believe? How much change did you experience?

Is there an orientation one should observe? I have a Chinese made CO2 laser which shipped with the lens installed curved side down, yet the forum wisdom suggests to place the flat side down and research done by others have proved it out.

With the G7 lens, is there curvature to consider?

Hi Fred,
When the lens came I tried it both ways around and one was clearly the right way (made a laser dot) and the other was not (made a large blurry light).

I think it was curved side pointing down but not 100% sure.

Once installed (it is a tight fit at first but loosens up) I screwed on a focus ring to help focus it in the exact same way as the original… Using the length of the focusing tool.
So when I put the shroud back on it worked in the same way (using the focus tool to slide under to leave a 1.5mm gap.

So it’s back to how it was before in every way, just a different lens.

Hope this helps!

Thanks immensely  for that Josh, Being clueless to the world of Laser Engravers/Cutters this will be a steep learning curve. I can’t wait to purchase both the Emblaser and G7. I’m sure I will spend many long long nights experimenting.

Hopefully with patients (haha) I will make less charcoal than I do matchsticks in my shed.

Happy Engraving 

You too Graham,
As of 1 month ago- I had no idea what I was doing.
Now I can make something cool from scratch in Cut2d and laser cut it in hours!

You soon pick it up, it just takes a good method of testing, lots of notes and lots of reading up on the community archives!

Josh,

To clear up some info in your posts.

Dominec said “The Emblaser 1 lens holder size is 9mm.”

In you last post you said “You need the 7mm lens and holder.”

I have looked at the web site and am interested in purchasing  a trial lense.

Which size lense is used on the 4 watt emblaser 1

Thanks

Thanks Josh. I just ordered one. It came to $16.35 Canadian. Now I wait to see how long it takes to get here and look forward to see what kind of results i get with it.

Yes I was correct.
The emblaser lens holder is 9mm.

I ordered the 7mm which screws into the 9mm hole.

If they were both 9mm they would not screw together.

I assume the 4w is the same size, as it is just the diode that is more powerful but you might want to check this with Domenic.

Jared, even though it’s from china, they send it first class so I got it in 3 days!
Hope you aren’t waiting too long!