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Dave Simms
12-09-2006, 9:49 AM
I am going to be installing a Universal X-660 in a workroom in my garage. There is a window right there but I live within 100 feet of a neighbor who will certainly question any venting that is being done out that window. (I would soon have the township inspecting the place).

I climbed up into the crawl space above the garage (a small attic) and I see that there are 3 unused vents leading out the roof. I realize that they vent hot air out during the summer but I now would like to attach my exhaust to one of those vents. It will be about a 20 foot run from the back of the laser up to the roof vent.

Anybody see any problems with this setup?

Thanks!

Nancy Laird
12-09-2006, 10:13 AM
Dave, you might want to check out this thread:

http://www.sawmillcreek.org/showthread.php?t=44936&highlight=laser+exhaust

to answer some of your questions. 20 feet seems like an awfully long run, and you will need an exhaust fan/blower. You will also probably want to muffle your blower, as they can be noisy and your 100-feet-away neighbor will probably complain about the noise too. You can get an in-line muffler that will damp the noise considerably. If you are putting the laser against an outside wall, you are probably better off venting it through a hole in the wall rather than trying that long a run.

We have two lasers hooked up to our blower, the run from the 20W to the blower is about 8 feet, and the pipe from the 40W goes directly through the wall.

52123

This is a photo of our set-up. Feel free to plagarize. The blower is a Dayton 3-phase with a Fuji AF-300 Mini 3-phase converter/controller, so you can control the speed of the fan. This set-up will allow you to draw the exhaust down and out of the laser rather than just hoping it makes it way into the exhaust--a must for vectoring wood and removing smoke.

The muffler keeps things quiet enough so that we can't hear it running until we are 5 feet or so away.

You can PM me for more info if you are interested.

Nancy

Dave Simms
12-09-2006, 10:34 AM
Nancy,

That is a great system and I will definitely look up that blower. However, if my neighbor saw that contraption on the side of my house, not only would he call the Township, he would probably call the Homeland Security Office. (Suburbia has its drawbacks)

I do appreciate the link for the search of Saw Mill Creek.

My engraving will mostly be wood, leather, marble, and Cermac on Stainless Steel. Am I correct in thinking that these are all low-stink processes?

Joe Pelonio
12-09-2006, 10:46 AM
Wood smells like a fireplace fire, leather smells like branding day at the coral. Marble and cermarc are low odor. I have a run of over 20 feet here but over powered the fan to 600 cfm rather than the required 400 to compensate with no problem. Tomorrow I move the laser to the house
where it will vent right out an adapter I made for a window. Luckily mine
will go out the side and we have a corner lot so there's a street between me and the next house.

Here I did have the Fire Department visit twice due to complaints from others in the business park, and both times they told me I was doing nothing wrong but asked that I try to run as much as possible early in the day during the hot summer (before people opened windows) just to be a good neighbor.

Nancy Laird
12-09-2006, 10:48 AM
Nancy,

That is a great system and I will definitely look up that blower. However, if my neighbor saw that contraption on the side of my house, not only would he call the Township, he would probably call the Homeland Security Office. (Suburbia has its drawbacks)

I do appreciate the link for the search of Saw Mill Creek.

My engraving will mostly be wood, leather, marble, and Cermac on Stainless Steel. Am I correct in thinking that these are all low-stink processes?

Thanks--LOML designed that system. Sounds like you have the neighbor from hell.

We haven't engraved any leather, and we avoid Cermac like the plague--maybe because we haven't had any call for it. But wood will give you only a burned-wood smell for a short time, no more offensive than a log fire. Of course the marble won't stink either. The really stinky stuff is for rubber stamps, which we don't do either, but from reading on other posts and forums, that stuff smells nasty.:(

Your profile doesn't indicate where you are. If you're in the vicinity of Albuquerque, we would invite you to come by and inspect our set-up.

Nancy

Dave Simms
12-09-2006, 11:23 AM
I probably will go out the roof, and will definitely go with one of the exhaust blowers that are mentioned by the fine folks above.

One last question. Does engraving on Silicone Wristbands smell bad? And, if I am just lightly engraving names and graphics on Acrylic trophies, will I have much of an odor (as opposed to actually cutting acrylic - which folks say is pretty bad)?

Thanks again.

Mike Null
12-09-2006, 12:59 PM
Your idea of going through the roof is great. Just be sure you have enough cfm--Joe's 600 number should be adequate. The odor may never be a problem.

I've been venting mine through the side of the house for 8 years and don't even smell it myself so my neighbors certainly can't.

Bill Cunningham
12-09-2006, 8:06 PM
I probably will go out the roof, and will definitely go with one of the exhaust blowers that are mentioned by the fine folks above.

One last question. Does engraving on Silicone Wristbands smell bad? And, if I am just lightly engraving names and graphics on Acrylic trophies, will I have much of an odor (as opposed to actually cutting acrylic - which folks say is pretty bad)?

Thanks again.
I don't know if the wristbands stink or not, I can't remember.. I guess I was just shocked by the amount of 'flame':eek: I was getting from them.. They engraved, but to do a lot I found they had to be spaced... w a y... out, or the vent air going through the laser caused the flame from the lower ones to singe the row above.. Nope, I was not using high power... At any rate, I found the engraving basically not to be worth the time or effort..

Ed Maloney
01-07-2007, 9:45 AM
Funny question, but I'm considering the PennState blower which is rated at 850CFM (http://www.pennstateind.com/store/dc3xx.html) (http://www.pennstateind.com/store/dc3xx.html%29). Most of the posts I see recommend around 500-650. Any negatives about having a higher than suggested CFM?

Bob Tate
01-07-2007, 9:49 AM
I have been using that very blower for almost 2 years now, at the far end of a 20 foot run. It really does a great job. I think you would have to go way beyond 850 to hurt anything.

Pete Simmons
01-07-2007, 10:23 AM
Check out some 8" inline blowers.Easy install - no noise

Scott Winstead
01-07-2007, 10:49 AM
I had a similar issue because my house is in a homeowner's association and I'm right next to a common area walking/running trail. The exhaust vent is almost 10 ft. from the common area walking/running trail. I started with an exhaust blower from Dayton (Grainger) that was just too loud (>90 db). I ultimately purchased a sound meter from Radio Shack so that I could measure what impact I was making with the various exhaust solutions.

After lots of false starts and partial solutions, I ended up with using a Penn State blower (DC3XX) that I keep inside the house very close to the laser in a wood surround case (3/4" plywood) that I built with 2" of soundproof foam and then vented to a 4" blast gate that goes out the side wall. I then connect some additional hose (~2 ft.) from the blast gate outside to a Penn State DC muffler (SUP1000).

This sytem works - the sound is now at (70 db) right at the muffler and has enough airflow (CFM) to vent the majority of smoke/smell effectively. A couple of things that I learned - the exhaust blower manufacturer's claims on airflow and static pressure are very suspect (i.e., I don't think there is a standard measurement that is consistent) and their sound ratings are also suspect (that's why I ultimately purchased my own sound meter). One of the considerations you should evaluate is that lots of CFM is good for airflow but too much and you're sucking all of the ambient air out of the house vs. your laser/room. So, one of the negatives of too much CFM is draining out all of that air conditioned or heated air in your house. Therefore, most folks try to find the right balance of CFM (airflow) and static pressure with air turnover in your house. It sounds complicated but once you start playing around with it, you'll realize the issues.

I won't do rubber stamps and only do acrylic and rowmark at certain times of the day. Annodized aluminum, tiles, and wood are the majority of what I do - these are all HOA/running/walking trail friendly.

Bob Kline
01-07-2007, 12:21 PM
My method's unorthodox (maybe "un"legal) but so far, no complaints from neighbors in my town home complex. I ran 4" PVC in a convoluted route from my Epilog up one floor, across the length of my garage roof then put an elbow dropping the end of the pipe from the ceiling to just above the top of the garage door. When I'm engraving, I raise the garage door about 2 feet which makes the blast from the PVC hit the angled door panel and deflect to the outside. Some of it meanders into the garage but quickly dissipates. I've been known to forget to raise the door which fills the garage with a rich aroma but that too eventually dissipates. The noise from the blower is audible but not annoying unless you're very near. Not ideal but workable and it didn't require an outside hole in the house which would have required association approval (or disapproval). Fortunately, I'm on the board. I should point out that I'm only using it about 15 minutes a day engraving and vectoring Flexibrass.

Pat Kearney
01-07-2007, 5:26 PM
The side of my house where the laser is located is about 8 feet from the side of my next door neighbours and their deck is located just behind this side so I have to be careful. I have my laser in my office with a hole in the wall to an adjacent laundry/storage room where I located the blower (a converted portable 800 CFM dust collector made by King Canada - I believe it may be Grizzly in the US by I'm not sure about that). From there I have it attached to a home made muffler (which to my amazement did cut the noise level by at least a half or even more). I then used 4" PVC pipe and using a couple of 45s & 90s exited it to the outside through the wall and straight up two flloors to my roof where I created a "H" shaped top with Ts that prevents water from entering the pipe. I had to add a blast gate inside between the laser and the blower to prevent cold air from coming down through the tube and entering the laser/room.

With regard to sucking your air conditioned air-or in my part of the world where we're more worried about heating-I am fortuneate enough to have a window in my office. When operating the laser I jar the window slightly and close the door to the room to prevent the heat from escaping. I do have some concern about moisture in the imcoming air but I only use the laser approx 10 hours a week and not all those times does the air contain high enough amounts of moisture to worry about.

Also worthy of note here is be careful if you use sources of heat such as oil, natural gas, or wood. Using a high CFM blower such as the types described in these postings can create a condition in your home called "negative air pressure" which causes the oxygen in your home to be lower than required for combustion, which in turn could lead to increased carbon dioxide from these burning units. What's worse if the suction of the blower then prevents the carbon dioxide from venting properly and sucks it back in to your home creating a very dangerous and life-threatening situation. Prior to my life in telecommunications I used to work at a company installing oil & propane heating systems and we saw this condition many times, especially in new, well sealed homes where bathroom fans, clothes dryer, kitchen fans, etc sucked the air out but new air could never penetrate the well sealed walls, doors, and windows to replace what was being sucked out. Lots of people complained of conditions such as headaches, itchy burning eyes, tiredness, etc. Anyway, enough of that - I think everyone gets the point :rolleyes: opening a nearby window should help prevent this from occurring.

Hoe this helps!
PAT

Wyatt Wolfe
01-09-2007, 2:20 AM
One thing I have not seen mentioned, and if it was.. forgive me.. but laser exhausts clutter up pretty quickly with debris - the inside of mine after only one month held several pounds of soot and dust... I suspect, that trying to vent straight up is not going to work for very long - with the majority of your soot and dust falling back in to the working area when the fan is shut down... might be a consideration for you...

Joe Pelonio
01-09-2007, 8:16 AM
One thing I have not seen mentioned, and if it was.. forgive me.. but laser exhausts clutter up pretty quickly with debris - the inside of mine after only one month held several pounds of soot and dust... I suspect, that trying to vent straight up is not going to work for very long - with the majority of your soot and dust falling back in to the working area when the fan is shut down... might be a consideration for you...

Good point, when I moved mine there was 1/8" of debris coating the inside of the exhaust from the machine to the fan, about 5'. I would suggest making an acrylic (clear) box at the point where it goes from horizontal to vertical with removable side. That will catch the debris, when you see a buildup you can open it and vacuum it out.

Mark Winlund
01-09-2007, 5:23 PM
I have a 2 hp high pressure blower hooked up to mine with a VFD. When it's really cranked up, the polycarbonate viewing window actually bows inward under atmospheric pressure. It really holds things flat on the vector table, though! The outlet run is about 15 feet.

Mark




Funny question, but I'm considering the PennState blower which is rated at 850CFM (http://www.pennstateind.com/store/dc3xx.html) (http://www.pennstateind.com/store/dc3xx.html%29). Most of the posts I see recommend around 500-650. Any negatives about having a higher than suggested CFM?

Pat Kearney
01-09-2007, 5:54 PM
I never checked my vent to see if there was any debris built-up at the bottom. I should check that!:rolleyes:

Jim A. Walters
01-09-2007, 8:13 PM
If you used 4" rigid PVC, you could install a "Y" with a threaded cleanout. If the exhaust was run about 3 feet (a meter for the rest of the world) up on the wall, you would have room to get the shop-vac nozzle up a bit to clean it out. I guess you could even use a small chimney brush (keep the shop-vac running and close! cough, choke).

I have attached my poor Corel rendition of a cleanout.

Mike Hood
01-09-2007, 9:39 PM
I did much the same thing. The vent is a louvered drier vent, and I only run it in the evenings after dark if there's any odor probable. I've walked around the side of the house to get an idea of the impact and it usually smells like any one of the ozens of fireplaces starting up on any evening around here.

DEFINITELY won't be running any rubber during the daylight... and preferably only with a stiff breeze :cool:

Scott Winstead
01-09-2007, 9:59 PM
Had a request to post some pictures of my set-up ... hopefully, these come out OK.

1st picture is inside my office and you can see the ULS laser and the sound enclosure box (3/4" plywood) over the exhaust blower. The box has 2" soundproofing insulation on the inside. We put a green tablecloth over it and use it as a table within the office. This keeps the sound down inside.

The 2nd picture is a top view of the sound enclosure box - two holes with one hose from the laser and the other is the hose going to the blast gate in the wall.

The 3rd picture is outside hose connected to external blast gate and then to Penn State Industries Muffler (SUP1000) - I think it sells for ~$80. This keeps the sound down outside ... I also add some "outdoor accessories" to camoflauge it from passerbys. :cool: