Cutting MDF problem

[aletof]

Hi,

Does anyone have any experience cutting 3mm MDF? I can't find a good combination of speed/power for it.

I am trying to create a jigsaw puzzle, but everytime I get 1 pf 2 scenarios:

-The laser doesn't cut all the way.
-The laser burns a bevel on the top part, making it around 1mm thinner than the bottom part, this is the only way I get the pieces fully cut, but they are no good because of the bevel.

Any ideas on ow to avoid this? Would I be better off using another material like triplay?

Thanks for your help,

Alejandro

[OldEngraver]

You will need to post the specs of the laser you are using in order to get an accurate answer to your question. My GCC mercury 25 watt will easily cut 3mm MDF at 100% power and 2.2% - 2.4 speed, but if you have a chinese laser, chances are that these figures won't mean anything to you.
From my information, the composition of MDF can vary widely, so we may not be talking about exactly the same material.

[lrob]

I would also suggest you post the focal length of the lens you are using also. This might be the cause of the "V" cut you are getting.

[aletof]

Thanks for the replies guys. The machine is in my University but I'll try to get information from it. Maybe see if the technician there knows something about the focal length. I'm almost sure it is a limac, one of the big models, maybe with a 120 by 90cm cutting area. The program is laser cut 5.3 and I don't think it has percentage units.

As for the mdf vs triplay question... Do you think it's less likely to burn?

Thanks for the help,

Alejandro

[lrob]

"triply", I assume that is what we call plywood. If you stay with an interior grade like Baltic birch, you will have less burn versus MDF.

[Alexis Martial]

I confirm other replies.
3mm MDF should cut like a charm even with only 40W CO2 laser.

The V bevel you experience is a little surprising since usually it's the bottom where the kerf is bigger due to heat accumulation and when the focus is on the surface [recommended to cut faster and reduce burn for wood].

Thus my guess si that you're cutting without enough [if any] air assist.
You NEED a strong air assist [at least 20PSI] of clean compressed air.
When I say clean I mean your air assist need at least to be free of oil and dust.

In most laser, the air assist pressure is adjusted manually so you should ask your technician for this or look at the head of the laser and try to follow the air assist pipe ;-)

Hope this helps.

______________
Alexis, Managing Director
Plixo, a Unique Boutique Workshop in Singapore
Laser Cutting and Engraving Services

[EXLASer]

Hi Alejandro,
Baltic birch is usually a good material to laser cut,the most dependable wood for laser cutting is basswood.
MDF edges char more and takes longer to cut.
I agree Alexis that changing a compresser enlarge air assist/ 20-50PSI to get nice effect.
Remember,the intent of air assist is to suppress the flaming or melting of the material during laser processing,,,
Annex 4mm wood and 3mm MDF cut samples our EXLAS done.
Hope info help you~
Mike
mike@xyz-tech.com

Originally Posted by aletof Hi, Does anyone have any experience cutting 3mm MDF? I can't find a good combination of speed/power for it. I am trying to create a jigsaw puzzle, but everytime I get 1 pf 2 scenarios: -The laser doesn't cut all the way. -The laser burns a bevel on the top part, making it around 1mm thinner than the bottom part, this is the only way I get the pieces fully cut, but they are no good because of the bevel. Any ideas on ow to avoid this? Would I be better off using another material like triplay? Thanks for your help, Alejandro