Fiber laser exhaust system?

[Bill George]

Just wondering if you folks with fiber lasers just engraving metals use or need a exhaust fan system?

[Naseem Khan]

We have a sealed enclosure with a 2hp blower pulling fumes and debris out

[Bill George]

We have a sealed enclosure with a 2hp blower pulling fumes and debris out

It looks like your running a large commercial or industrial machine, this is only 20 watts. Perhaps I should have been more specific.

[Gary Hair]

I have one exhaust fan that I use for my co2 and both fiber lasers. It's rare that I laser something on the fibers that I really need to extract the fumes, mostly it's metal - aluminum and steel, and I have no idea if they have any byproducts that I should be concerned about. There is a fair amount of dust buildup on the fiber between the parts and the exhaust, so I think something is needed. I'm moving next month and I'll use a carbon filter for the fibers and return the air back into the shop, probably put a pre-filter to catch dust, etc., and let the carbon take any smell out. I'll still use the big blower for the co2, I do a fair amount of wood, acrylic and other noxious materials so it's really necessary.

[Kev Williams]

I just Macguiver'd up this 4" tube Y'd into the LS900 blower...
fibex2.jpg
Since this pic I've found that the big 6" opening on the 4" pipe is almost useless because the 4" pipe doesn't create much air current; about as much smoke drifted away as it sucked up. I've since suspended the pipe from the ceiling better (uh, yeah ) and put a $4 HF blast gate on the end of the pipe. It's positioned just above to the right of the lens head. Opening the blast gate about half way really speeds up the air movement, and it draws nearly all of the smoke in. If you're not sharing a blower with another machine, I'd recommend using 3" pipe, and experiment with where the smoke naturally goes and then put the pipe as near as possible, just above the lens. Up there, it'll never interfere with the work (like it could in my pic above).

Since you're not evacuating a cabinet of smoke, it doesn't matter if the 3" pipe reduces air flow volume, because what you need is air flow speed. The farther from the end of the pipe the air is moving, the more smoke it'll find.

[Ken Tan]

When I got the fiber laser and burn my first aluminum fixture, the smoke alarm went off at the middle of night!!

Now I bought a Pace fume extractor off (EVA 250) the eBay, and has been using it daily.

The advantage is it is an indoor unit, and it is cold during winter time in mid-Atlantic. Can't afford the heat lost in the basement.
The sound level is tolerable as well.

The down side is the filter need daily cleaning and cost of brand new filter.
A brand new filter unit cost over $200. A pre-filter or a 10x10 filter cost $6

A brand new Fumex mini or Pace 250 machine will cost over $1500.