Cutting white fabric without burn marks

I’m trying to cut fabric for embroidery, etc… On dark colours it’s not noticeable but on white or light colours there is a faint burn mark where the fabric is cut! I’ve seen product that does not have these marks! I’m using a Chinese laser, works great for everything else, any ideas?

You did not describe what kind of Chinese laser you have. (arn’t they all Chinese?).
What kind of fabric?

Either way, I suspect you need much higher power plus air assist.

Thanks for the reply Sal. My laser is 60 watt and it has air assist. Not sure how higher power will reduce burning. When I do wood I will use use low power and multiple passes, the result. Is almost like a router did it, hardly any burn! I’m going to try this on cloth. It’s heavier cloth with embroidery on it to make patches for jackets, etc.

This should blow though most fabric instantly. Maybe your dwell time/speed is too low. Have you tried to optimize by increasing speed? Increase speed till it does not cut through then back off a little.

That settings can be specific for particular fabric type and color. So, optimize for each.

This is largely dependent on the amount of heat applied and the fabric’s material. I’ve had good luck either running multiple light passes on fabric to reduce the burn effect, or playing with both the air assist and downdraft flow. Sometimes sealing the entire table and pulling a vacuum on the fabric can cause the vaporized material to suck straight down rather than dirty the top surface of the material.

That is if cabinet is saleable and any meaningful vacuum can be created. I have not seeing one that can be sealed.

But Colin got good rationale here: removing oxygen should prevent charring. I think more practical will be to attach canister of pressurized non-flammable gas to/instead of air assist supply. This is exactly what MIG welder does. It creates local volume free of oxygen.Variety of gasses will work: nitrogen (not nitrogen oxide!), CO2, and any inert gas. This is not expensive at all. Can use paintball CO2 tank ~$30, pressure/flow regulator ~$20. +some adapters and maybe hoses.
That laser I can imagine cut very fast, probably single minutes. So this small tank will last.

Hermann, let us know if it works?