OOOOoooo we are having BIG issues with exhaust noise now that the weather is getting warmer and neighbors are opening doors/windows. I'm so concerned of the 747 impression we're producing here!

I can't wait to read more tips/tricks on this thread! Keep them coming!!

So Harvey - can you use a 4" car muffler for this application?

Pardon me...I'm just a girl! :)

I think you willl have to try a Diesel Truck surpressor for a 4" pipe.

How much CFP are you pulling ??

1100 CFM....... How far is the laser from the vent outlet..........

Just 1 laser or is there more hooked up??

I'm running just under 300 cfm and I can push 15-20 feet with no problem

Right now, the laser is only 6 feet away from both the blower and exhaust hole.

My current set up has the motor at ankle level on the floor with it venting directly via a dedicated hole outside. (this setup is in a garage.)

We want to change the config so that the vent hole will be farther from the laser - approx. a 30 foot run - thru 4" PVC. We also want to vent it out thru the roof making it push 30 feet and up thru the roof.

Do you know if it will be quieter if I use this setup or would you recommend some sort of muffler?

I should hope that by venting through the roof the noise factor would be projected up out of ear shot.

How noisy is the unit running on the floor by your feet??

I'm not a noise expert but I believe the current setup of the exhaust directly venting to the outside with no piping/tubing between the exhaust and the outside is the problem. It is incredibly loud.

There is 6' of flex hose from the laser to the blower and then there is 8" from the exit of the blower to the outside.

But before my husband begins cutting holes in the roof, etc., I'm hoping to get some type of reassurance that it's only got to get better (i.e. quieter on the outside) with his efforts.

But where is the fan unit going to be loacted??? up in the attic???

That's what is making all the noise..

Is the Smell a major factor to moving to the roof. If not a small fan is in order...

Just my recomendation. At 300cfm I have to check the "on" switch to make sure mine in even running.......

Well now that's interesting....It is the noise - not the smell - that is a major concern. There is absolutely no question when mine is on.

Maybe you've got a point...my unit would not be moved in this new set up. It would stay on the floor in the shop. My thought (or wishful thinking) was all this PVC run of pipe was needed to get the noise level down. But maybe what I need is a smaller/quieter blower??

What unit are you using?

You say you have to even check your 'on' switch to see if it is running. How is the noise from the outside?

It's not a good idea to leave the blower next to the laser and try to push the air through 30+ feet of pipe. The blower should be at the end, pulling the air through the pipe.

Your blower sounds like overkill first of all. If it's 1000 CFM, that's more than twice the CFM Epilog suggests for a mini.

If you build a box in the attic for the blower, and insulate the box, then blow up out of the roof, I would suspect that most of the sound would be contained in that box.

You can run a remote power switch down to the laser room and simply flick that switch before you start lasering.

BTW, use straight wall ducting for the exhaust to cut down on resistance in the pipe and the resonance caused by flexible tubing.

OK - looks like my Epilog rep may have suggested a too powerful (and noisy) blower. Not his problem...that's my mistake for not checking that part out more closely...

So what is the quietest blower with a 400 CFM minimum capacity? Anyone have any recommendations?

OK - I've found out some more info...

My blower is a 850 CFM. Epilog manual says for the mini to use a minimum of 400.

I've been looking online at inline blowers. Anyone using that as opposed to the portable exhaust blower setup?

I use an Inline

http://www.continentalfan.com/pdfs/axcduct.pdf

No problem meeting my needs.

OK - this is exactly what I'm thinking~!

Now which blower do you have? There are about 20 listed on the spec sheet and none that specifically matches your 300 CFM statement above.

Thanks in advance!