Cutting 3mm baltic birch

I’m having issues cutting through 3mm Baltic Birch. at the moment I’m set at speed 10 and power at 85 and my 100w Omtech struggles cutting through at times. Also it burns the edges. Yes I’m focused properly. I feel that the settings are too high. My laser is a half year old and should be cutting much better than this. Is there other settings I should be looking at to get way better results?

Sounds as though you have some other issues. Of course it could be the tube but first, clean the focus lens and all the mirrors. Do you have an amp meter on your machine? If so run a test and see what your average is when it is cutting or supposed to be.
I am running a 60W/50W Omtech with a 50.8mm lens. I can cut through 6mm birch ply with speed at 15 and power at 25% and the amperage is at 11mA.

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II did clean the mirrors. and checked the alignment of the mirrors

how do i know if i have an amp meter on my machine and how do i run a test to check it

I do have to ask this also. what is the max power suppose to be set at on the machine?

If you haven’t mounted one on it you probably don’t. My machine has an lps (laser power supply) that has a digital meter in it. You have to have the electronics bay access panel open to use it.

Max power on the machine console is for manual firing. If you set it to 60% and ‘fire’ it, it’s at 60%.

Many of us have added a mA meter (on the left) to keep an eye on the current. The digital ones ‘sample’ and generally seem to jump around a lot.

I doubt you have a power meter for the laser, like a Mahoney… It’s the best way when you have an issue like this.

Russ Sadler sells a ‘dohicky’ for lasers also, if you’ve seen his videos.

I measured mine when it was new, so I can measure it at any time and see if there is a reduction in power.

:smiley_cat:

i do have it at 60% max power. i ran a test at a speed of 15 and power at 25 and it doesnt come close to cutting through

Where? On the console or in the cut layer?

Is there where you ‘used’ to cut it without an issue?

Do you have a mA meter on your power supply?

Here is my LPS with the digital mA meter circled.

:smiley_cat:

the 60% setting is on the console. iwill check if i have a meter on my power supply

yes i do. ran a test at 15 speed and 40 power and it reads 14 mA

ran a test now at 10 speed and 60 power and the meter read 21mA

That sound reasonable as your max is 30 mA and 50% would be ~15…

Speed is not needed if you’re looking at current draw itself.

Sounds relative linear. An increase of 50% power (40% → 60%) gains you a 50% increase in current (14 to 21mA). I’ll leave out that co2 tubes are ‘negative resistance’ devices when they lase…

Have you checked the outlet at the tube?

Never know where ‘junk’ will get with these machines.

:smiley_cat:

in comparing i also ran at 15 speed at 25 power and got 8mA

ste max power on the console is 60%

You need to set your layer that you are running to the proper speed/power. Console setting is only when you fire it from the console. That max is ignored during a normal layer run.

There is also a question about min power on your layer…?

If you are using a ‘minimum’ power setting on your layer and the ‘Start Speed’ in the controller it greater than your speed, you will only get minimum power.

May wish to try and set your min/max to the same cutting power…

:smiley_cat:

i will try that

i do have min and max set the same on the cut layer. speed on the controller is 300ms

So this isn’t true?

I don’t doubt you can’t cut through at 300mm/s.

I don’t think we are communicating.

If you have a job that is ‘running’, it’s min/max and speed come from the layer that is executing. This is what you are concerned with.

If you are moving the head around the controller uses what’s set from the panel. Same with ‘pulse’ of the laser when using the machine console.

This makes it more difficult if we can’t talk about the same item consistently.

Just out of curiosity, do you know the any of the axes ‘Start Speed’? Mine was set high at 20mm/s some are set low… Since your min/max are equal, it’s not going to be a problem.

:smiley_cat:

sorry i meant 3mm baltic birch. where do i find the axes “start speed”

I have a 100W Blue & white with a RECI tube. I cut 5 mm a lot at 13 mm/s @ 65% Max Pwr == Min Pwr, and I think that might be a bit high on power. But, some plywood has more voids in it that others. So, this is 5 mm Baltic Birch ply cut with one pass. 3 mm would be much, much easier. Mirrors cleaned daily, lens cleaned at least once a week. Alignment checked weekly. Voids and knots really don’t like to be cut …