Extraction and Heating

[Jiten Patel]

So you guys run these extraction systems, which obvsiouly suck out all the air in a room and dispell is outside, what do you do about heating in the winter? How do you keep warm, apart from huddling together....:)

[Mike Null]

Jiten

You raise a good point but many here seem to buy power/price and don't consider the consequences of that power (excessive cfm, noise, loss of conditioned air).

[Jiten Patel]

Well Mike,

I am finding out the hard way. I bought a harbour freight type model (UK equivalent), and firstly it seems way too powerful, and its way too loud.

I have tried everything to dampen the sound....enclosure with insulation...didn’t really work. Need to invest in some high density acoustic foam to line the enclosure....not the cheapest stuff around, but saying that, I would probably spend that amount on head ache tabs in a week!

But with that problem being solved, heat is now an issue. With the Winters getting colder and colder and having this extraction unit sucking out all the nice warm air from the building, not really sure what I can do apart from wrap up warm.

Also, this may seem obvious, but having such a powerful extraction unit/dust collector, doesn’t this create a vacuum in the room? I know cracking a window solves this, but this brings me full circle back to heat!

Oh the dilemma!

[Dan Hintz]

This is the reason a number of us have built filtration units so we can exhaust back into the room. See my post on a sub-$200 DIY unit...

[Michael Hunter]

I find that a 2KW fan-fire about balances the heat lost through exhausting the laser outside.
I don't freeze, but it is not very economical, nor good for the planet.

I have an idea for adding an air-inlet vent in the wall and using a flexible hose to bring the cold fresh air right up to the front of the laser - this should cut down the ammount of warmed air that is lost.
Another idea is to put a "curtain" over the laser air inlet, so that the laser picks up air from near floor level where it is coldest

[Jiten Patel]

Not sure that would work for me as I will be running my laser as a class 4 - no enclosure for me....but the sub $200 air scrubber might work. Does this get rid of smoke or just toxic nasties in the air?

[Dan Hintz]

Smoke is a toxic nasty... it gets rid of it all if designed and sealed properly.

A month or so ago I engraved a 16"x28" maple plaque at 100P... took about an hour and 15 to do, and there wasn't a hint of smoke in the room (and I can assure you a ton was pouring out of the back of the machine into the exhaust). There was a faint odor of wood in the air, but it was a pleasant and light smell (I'm very sensitive to smells), like when you open a cedar chest. I could probably get rid of even that faint smell if I increased the depth of my charcoal bed (it's at around 2" now).

[Jiten Patel]

Smoke is a toxic nasty... it gets rid of it all if designed and sealed properly.

A month or so ago I engraved a 16"x28" maple plaque at 100P... took about an hour and 15 to do, and there wasn't a hint of smoke in the room (and I can assure you a ton was pouring out of the back of the machine into the exhaust). There was a faint odor of wood in the air, but it was a pleasant and light smell (I'm very sensitive to smells), like when you open a cedar chest. I could probably get rid of even that faint smell if I increased the depth of my charcoal bed (it's at around 2" now).


Right, that sounds like a plan.....let me get my building hat on and see what I can come up with! Cheers Dan, you infinitate well of knowledge you!:)

[Robert Walters]

I have tried everything to dampen the sound....enclosure with insulation...didn’t really work. Need to invest in some high density acoustic foam to line the enclosure....not the cheapest stuff around, but saying that, I would probably spend that amount on head ache tabs in a week!

I have the HF red dust collector:
http://www.harborfreight.com/1-hp-mini-dust-collector-94029.html

As a test I tossed it into a Rubbermaid heavy duty commercial plastic trash can. The sound level dropped dramatically. I would say to around the level of a cheap 20" box window fan on high.

There was still some vibration, but that is from the blades not being perfectly balanced so I have bought some rubber mounts to dampen the DC.

When it comes to acoustic foam, I found it expensive as well. Plus the fact that you must make it fireproof somehow. http://en.wikipedia.org/wiki/The_Station_nightclub_fire

Doing some research on sound dampening, the material you want should be "heavy and soft". http://en.wikipedia.org/wiki/Soundproofing

I found two things that fit this criteria:

1) A recycled rubber floor mat at Home Depot for $10 and even had the same pattern used in real acoustic materials as a bonus.
http://www.homedepot.com/h_d1/N-5yc1vZ1xgl/R-100671772/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

2) Ceramic wool (fireproof to 3000F) and pretty heavy for it's size.

There is a third item called 'sound board' that comes in 48"x96" sheets for about $15 at Home Depot, but in BIG FAT LETTERS across each sheet it says: "IGNITION SOURCE, AVOID SPARKS OR OPEN FLAME" so I avoided that.

I am building my air scrubber with the dust collector mounted inside of it.
That way it serves to take up less floor space, cleans the air, and reduces noise level all at the same time.

Hopefully this sparks some ideas your way (no pun intended).

[Tom Bull]

Also, if you duct air from outside, be careful about ambient air temp going to your unit.

[Mike Null]

I'm still of the opinion that a properly matched blower will do the job without all the other downsides. You may have to pay $400 for it---or less, but you can find what you need by going to an industrial supplier. Woodworker's dust collector type equipment is fine but there are drawbacks.

While I like Dan's filter design I would only use that where I didn't have an outside venting option.