Laser fume exhaust: vent to attic, outside, or fume extraction?

[David Somers]

Jeffs approach is similar to what I described, with the exception I am under my house and Jeff is above it. Same idea though. One suggestion if you did this. Consider putting a smoke detector in whatever space you put the fan in. And mark your calendar to change its battery annually. You might also put a camera of some sort down there that you can access remotely.

Can't blame you for not wanting to go out a brick wall. I wouldnt want to do that either. But adding extra hose/pipe to get over to the window shouldnt be an issue in terms of the overall length if that helps. Especially if you are using smooth walled pipe, the distance you describe should be fine. For what that is worth!

[Kev Williams]

What you really should shoot for (IMO) is to get the blower OUTSIDE. As long as it's INside you're smoke & soot & stink into your house. My garage blower is still in the garage and engraving leather sucks in there! My basement lasers's blower is outside, and the air down here is nice & clean.

I have the big HF blower outside in a shed next to the house. I got tired of burning up shop vacs that I was using- and their noise- as chip extraction vacuums and have been using this blower for 13 years. No, it doesn't have anywhere near the suction of a a good vacuum cleaner, but it's dead silent, and even funneled down to the 1/2" hose that's connected to my machine's depth gauges, there's plenty of draw to suck up the engraving cuttings. I rarely have the end cap off but I do take it off occasionally so the heavier chips that just sit in the vent will suck back to the vacuum. I have two 25' dryer vents connected together, and there's still GOBS enough airflow to suck 2 laser's worth of smoke out if needed...

Proving again that I'm the king of underkill, here's the vent run, it starts with the black hose that connects to Don's C2000,
from there it runs along the ceiling, 38' to the side of the house and out into the shed and the blower...
DSC06074 (Medium).jpgDSC06075 (Medium).jpgDSC06076 (Medium).jpgDSC06077 (Medium).JPG
The dryer vent is also 13 years old and still in good condition.

In the first pic above, you can see the LS900 vent run up the wall, across the ceiling, and down the door jamb, where a Y pipe connects a second vent (hard flex aluminum) that sucks the smoke from my fiber.
That's nearly a 25' run with an against-the-wall 90, plus 3 more 90's once out the door, plus a second wide-open pipe...

To show how well it pulls smoke even with all that cheap pipe and bends, in this pic I'm running the LS900, door wide open, and hard- engraving wood 16" down,
pretty much out in the middle of nowhere, AND with the fiber's blast gate open (look close)-
DSC06238.jpg
While there is smoke drifting up around the back of the cabinet, you can see the smoke being
pulled to the back of the cabinet, and NO smoke leaves the cabinet.
(this also speaks of Gravograph's way of exhausting, it simply works great)

This is the smoke exhausting with the other blast gate closed,
notice the smoke is going straight back...
DSC06240.jpg

So, just my 2c but I wouldn't about long runs or what pipe to use. We don't need a 100% efficient hospital-grade air ventilation systems, we're sucking smoke out of laser engravers!
A 30 or 40 CFM airflow loss out of 4 or 5 hundred CFM doesn't add up to a hill of beans as far as extracting smoke from your laser. That little bit of air loss is well worth the clean air you'll enjoy.

[Bill George]

Be very aware like most Chinese imports I am sure they "stuck" a UL label on that fan. I would bet a lot of money it means nothing, as UL means it was tested and approved and that means time and money. My just the UL label (if it has one) perhaps means the cord is approved!
I would consider any Import from China or India to be a fire hazard. Sticking it (your fan) in an attic or un-attended area is just asking for a fire.

[Keith Winter]

For what it's worth I've tossed a number of those green Chinese blowers, utter junk. The $80 harbor freight would be well worth your money to upgrade. With a coupon you can get it even cheaper some weeks.

[Kev Williams]

The blower that came with the Triumph is pretty much identical to the one in Robert's pic, but 220 volt. I was impressed at the amount of air it blew. But one day it simply wouldn't kick on. I tested the power outlet, it was fine, fan freely spun, just no worky. Wasn't worth digging in farther when a new Harbor Freight unit was $138. I have nothing but good to say about these- The one connected to the lasers I got in 2004 when I got the LS900. The one before it I got in 2002, last year a motor bearing started a high pitched squeal. I could've spent my time (which I have very little to spare) to change it, or pay the motor shop $80 to do it. At 14 years old it served me well. I didn't even replace it as the second one does fine by itself. The big one in the shed I got shortly after small one so it's nearly 13 years old. The one in the garage is going on 3 years old. Fact is, I have good luck with most HF products.

[Matt McCoy]

If you're cutting a lot of acrylic and ABS, the sticky residue left on the cutting surface, as well as the inside of your cabinet will continue to off-gas and linger. The current collector you're using is a beast and will move a lot of air. The CFM is about the same as the HF 1 hp dust collector and both are made in China, so my opinion is that location of the extractor will make the most impact. If your compromises won't allow you to place it in the optimal locations that have already been suggested, then some concessions will probably have to be made in regards to smell and noise. Everything else might just be rearranging deck chairs.

P.S. Dave's solutions are always the coolest! So much thought goes into everything. Your shop must be almost like the Batcave.