[slow_rider]

I tried cutting at 2mm/sec with 95% power and air assist and it came out ugly and did not went through. What is wrong?

[Pplug]

Dirty optics / bad alignment

[smiz]

looks like a lot of flaring occurred. I would drop laser intensity down and adjust the speed of the cut. I have been running cuts at 20% at 5mms to do most of the things i need.

[slow_rider]

I checked the mirror on the cutting head and indeed it was dirty. I had a new mirror so I swapped it, did a small change but not too much. BTW - I need to adjust the distance of the mirror and the focus lens on the cutting head as well? How do I do that?

[grahamedale]

Im having the same issue, although out of the box it cat 3mm ply like butter but then after a couple of cuts it wont cut through now no matter what time of power setting it is on, all mirrors are clean and lens looks good

[Pplug]

Im having the same issue, although out of the box it cat 3mm ply like butter but then after a couple of cuts it wont cut through now no matter what time of power setting it is on, all mirrors are clean and lens looks good

It sounds like your laser is loosing power due to heat. Check your cooling system.

[grahamedale]

It sounds like your laser is loosing power due to heat. Check your cooling system.

Hi Thanks for the reply, its running at 62F 17C so should be ok from what ive read.

[2_many_hobbies]

I cut 3mm baltic birch last night. 10mm/s at 20ma (of 25ma max) with 20psi air assist. Too cold of water somehow reduces laser power as my ambient temp is 18c but I cut the best with the water at 21c (Measured at tube outlet not the reserve tank temp)

Cut perfectly.

[miketola]

Okei if you have scandinavian Birch plywood that means you vant cut it . Why? Because of they use new kind of glue. With that glue its almost water resist.
Old glue was urea glue and that you can cut easily. If its burn black and smels and smoke, you have "wrong" plywood.
I have in stock 4mm plywood what i can cut 25 % power and 10mms easily. I also have 2mm plywood, what need power 80% and 10mms..

Where are you from ?

[slow_rider]

Currently I have another type of birch plywood (does not seem to be any superior quality). I can cut 3.8mm thick at 50% power (from 40W) at 10mm/sec. If would also cut at 40% however sometimes the wood at the bottom of the part won't cut all the way through. But mostly it does. I think the relative high power is also due to not being able to adjust the laser beam perfectly. I tried for very long time but it simply can not be aligned in such a way that it will hit the center of the 2nd mirror at all positions and because of that it is not possible that it will hit the center of the cutting head at all positions so I think 1 of the corners is a bit "weak" so the extra power makes up for it.

I have a feeling that better plywood is out there but I have no idea where to buy it from the local wood warehouses are very amateurish and they don't even know what is the grade of the plywood not to mention to what standard it conforms. I am from Israel ya?

[wklaserliu]

hi FRIENDS,

Yes, it is ok to cut 3.5mm birch plyood using 40w, ,jusr rise power and reduce speed, then ok,
our storm600 40w is ok , early we try on it, speed is little slow when cutting hard wood.

QUIVEN FORM GWEIKE LASER

skype: wkquiven
[email protected]

[herby08]

hi there
the frame X and Y rails need to be square that's most importand!!! you need to check this with a square see picture.
the beam need to be dead center on all four corner of the table.
greetings
waltfl

[slow_rider]

Thank you very much, I can understand that of course however I am wondering how can I adjust the angle on the table?

[miketola]

Loose your belts and just put it right, this is very common problem.

[slow_rider]

I understand the procedure, however the machine only has 3 screws between each beam to the adjacent one, how does that allow control on the angle? I think it will always return to the same position.

[slow_rider]

If it would be possible I would like to hear about this... how can I actually change the angle of the beams if the holes are already threaded?

[Mcbride19]

What is your laser lens focal ? certainly 50,8
Change for a laser lens with focal 38,1, it will do a better concentration of the laser beam. With a 50,8 I was unable to cut 3mm plywood, with a 38,1 focal laser lens it cut perfectly !

[slow_rider]

@Mcbridge19 - it is 50.8mm focal length. So you are suggesting that it is focused too far down (beyond the cutting table)?
My lens is 12mm in diameter, seems like the 38.1mm mirrors are larger, so this won't fit my cutting head?

[Mcbride19]

It simple, it took me a long time to understand but with the help of Miketola it becomes more clear.

If you are using a 50.8 focal lens ,then you need to distribute a lot of power to cut. A 50,8 mm focal can cut a thicker material because the DOF is higher but needs a lot of power.
A 38,1 mm focal have a DOF of 6 or 7mm but needs less power (it concentrate more the laser beam).
For example: when I had a 50,8 mm focal lens , I needed to put 90% power(sometimes 99) and 6mm/s speed to cut. With the 38,1 focal lens I need 24 % of power and 10 to 12 mm/s speed and it cut perfectly
Higher focal lens gives higher DOF and needs more power(so it can cut thicker material) and lower focal lens gives lower DOF and needs less power.

Do you have a standard k40 laser engraver ? if it is ,so you can , certainly, put a 18mm lens inside the head(that's what I made).


This is the thread where miketola explained to me how focal lens works:
http://www.cnczone.com/forums/genera...laser-50w.html

[miketola]

And if you like engrave you dot is smaller so you can make high quality engraves. With 38.1 lens power is allmost double, dot is smaller and you can cut max 6-7mm. I cut 4 mm birch plywood 20% and 10mms. It cuts 16% but because i need high quality i use 20-23 %