[bday]

Hello!
When I set my laser to cut a square at the top right corner it cuts it out, but as I set the machine to cut the same square at the bottom of the table it only marks it. The laser does not go trough. When I adjust the cutting power or speed it only marks with a thicker line. I have attached pictures. Can anyone tell me what seems to be the problem? and what do I need to adjust in order to fix it?

[TehPepper]

It appears to me the distance between the material and laser head is different at the bottom of the table than the top. This could be an uneven bed or a bend in the material. Can you verify this?

[bday]

It appears to me the distance between the material and laser head is different at the bottom of the table than the top. This could be an uneven bed or a bend in the material. Can you verify this?

The material is straight. But I will check the bed. If the bed is uneven hhow do I align it?

[KeithOKC]

Sounds like you bed is uneven. Try measuring from the head to the bed in all 4 corners and then the middle. If any of those corners are different then your bed is not aligned, if the corners are the same but the middle is different you have a sagging bed. Then determine if it's your cutting table or bed that holds the cutting grid that's off. I've never leveled a bed but I would think you would just adjust the screws below the bed. Try searching the forum.

[blh8426]

What kind of machine is this?

Sent from my SAMSUNG-SM-N920A using Tapatalk

[SevenQQ]

Check the cutting table or your paper ,whether it's uneven or not?
Best regards........Seven

[minicncuser]

I bought a cheap one off ebay it did the same thing the laser beam was off there is a few youtube videos on it mine was easy to tell I just taped a card in front of the mirror and I have a test button I tried it close the I moved it all the way one the same axis hit it again and it was about a 1/8 inch off I played with it for a bout 10 mins I must have got lucky but no I can cut any where on the table look at the videos

[bday]

Hello!
Yes I checked the bed, It bends towards the middle. Its the honeycomb table its saggy. I will try with the knife table only, to see if that is the broblem. Will report back.

[bday]

I changed the table and tried to cut it again. I autofocused the laser in every cutting place to make sure it is focused.
As You can see in the picture the laser still did not cut through .
I have a OMNI laser cutter 100W power 1300x900mm table.
what else I can try to do?
Maybe it is the focal lens which is inside the pointy thing. - I know that I need to regulate it with the third mirror screws but when I tried I made it out of focus so it made a very big dod so I turned it back so it made a small dot. Do I need to take the focal lens off to see if the laser makes the dot without the focal lens? Maybe it is not regulated right in the 3rd mirror?

[gfacer2]

1) Have you ensured that your beam is aligned as per the many tutorials out there? If not - do that first.
2) Have you now leveled your bed in relation to the laser head. As mentioned, the distance from the bed to the tip should not vary anywhere on the table.
3) Are you sure that the auto-focus is set to the right depth? It doesn't sound like it is set correct. And are you setting it to the table or the material face?
4) If you adjust the speed and power, can you get it to cut at all in the problem area? If yes, what settings work there vs the rest of the table.




I ask these questions as the beam does have a power drop the further it gets from the beam so yes, if you have it 'just' cutting in the upper left corner, then the lower right will likely not cut.

[bday]

1) Have you ensured that your beam is aligned as per the many tutorials out there? If not - do that first.
2) Have you now leveled your bed in relation to the laser head. As mentioned, the distance from the bed to the tip should not vary anywhere on the table.
3) Are you sure that the auto-focus is set to the right depth? It doesn't sound like it is set correct. And are you setting it to the table or the material face?
4) If you adjust the speed and power, can you get it to cut at all in the problem area? If yes, what settings work there vs the rest of the table.




I ask these questions as the beam does have a power drop the further it gets from the beam so yes, if you have it 'just' cutting in the upper left corner, then the lower right will likely not cut.

I have set the laser beam right it hhits all the mirrors at the same spot. I am autofocusing to the material face. It could be that the autofocus is not set right because I have not checkchecked that because I dont know how. Could you tell me how to check that?
Now when I aligned the mirrors aagain the machine makes the same making in every pplace of the table bbut it does not cut. I tired to change the power and spspeed bbut it still does not cut. So the power is lost somewhere. The material is 3mm plywood. Could it be that the autofocus is set wrong?

[TehPepper]

What gfacer2 said but perhaps your auto focus is not set for the correct distance. In your original picture even the 'good' cut looks a little wide. See how narrow a line you can get by trying different distances.

And in addition what speed and power are you cutting at?
Have you checked your mirrors and lens is clean in additional to the alignment?

[bday]

What gfacer2 said but perhaps your auto focus is not set for the correct distance. In your original picture even the 'good' cut looks a little wide. See how narrow a line you can get by trying different distances.

And in addition what speed and power are you cutting at?
Have you checked your mirrors and lens is clean in additional to the alignment?

The lenses are clean I have checkchecked. I cut speed 40mm/sec and power 60. Then I tired also power 80. But nothing changed. I have a 100W laser.
Could it be ppossible that the laser is damaged?

[TehPepper]

With my 40 watts laser I cut 3mm plywood at 100% power and 17mm/s. 40mm/s seems way to fast for 60% power on a 100 watt laser.

Please try a lower speed and see how you fine a line you can get by altering the distance between the head and the material.

[gfacer2]

Could it be that the autofocus is set wrong?

Yes - If yours is like mine was (before it burnt off and was not replaced as it was somewhat useless/inaccurate) then it can be set to multiple heights based on the lens you are using. Lets say you have a 50mm lens in (most common I think), then you want to make sure the distance from the material to the face of the lens is 50mm. Usually this is not a practical measurement so you can do it in 2 steps. 1 is lens to some point on the outer cone (on mine 8mm) and then from the reference point on the cone assembly to the table (in my case 42mm). Many people just cut little spacers at the 42mm size (or whatever your size is) and never use the autofocus. The autofocus is a great marketing feature but not required in actual use and eventually it will fail/burn/be inaccurate.

[fixtureman1]

I would use the slant test. Put a piece of your material in the laser wit one end lower than the focal point and the other Raised higher than the focal point. Draw a line and cut it then check where it is cut the best. Move your head to that spot and measure it that is you focal length. I then make some gauges.

[KeithOKC]

1) Have you ensured that your beam is aligned as per the many tutorials out there? If not - do that first.
2) Have you now leveled your bed in relation to the laser head. As mentioned, the distance from the bed to the tip should not vary anywhere on the table.
3) Are you sure that the auto-focus is set to the right depth? It doesn't sound like it is set correct. And are you setting it to the table or the material face?
4) If you adjust the speed and power, can you get it to cut at all in the problem area? If yes, what settings work there vs the rest of the table.

I ask these questions as the beam does have a power drop the further it gets from the beam so yes, if you have it 'just' cutting in the upper left corner, then the lower right will likely not cut.

Excellent tips from Gfacer2 I second everything he said here. Best to contact your manufacturer if you need info on how to adjust the auto-focus. Also play with different speed settings you might be going too fast or too slow. From what you posted it seems like you are going way too fast. Google and forum searches are your friend.

[klawndyke]

mine did kind of the same thing to find out it was the focus lens had hair line fractures

[bday]

Hello!
Thank you all for your help!
Right now I am aligning the table and trying to get the right focus. Will report back later to let you know how I am doing.

[bday]

Hello!
I have leveled the table and set the right focus. Now everything works. If anyone ever need to focus here is a good video https://www.youtube.com/watch?v=j-b3pomqKkI.
Thank you all for your help!