Laser Exhaust blower questions/help

[Lenin Alvarez]

Ok here is the deal we have 2 lasers on our shop and we are getting two new ones next week, of course we need new exahust for them. Currently we use an Impell Filtermate 1500 wich works ok for both machines (unless we are working on wood or cutting plastic :confused:) we are going to use the filtermate for our oldest machine since it is really expensive to keep replacing filters.
We are going to set up 3 machines ULS V460, Epilog Helix24, Fibemark, (each of these are rated to 400CFM) next to each other and set up an "normal" exaust system to the outside.

Now since most of you guys seem to use this system i would like to know

-Can we use a single blower for the 3 machines? we were thinking this one
http://www.pennstateind.com/store/DC250SEMB.html

and maybe connecting it to this speed controller
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=43060

-Would you recommend using 3 or 2 smaller blowers instead of the big one
lets say this one

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=94029

The blower/s will go on the roof

Do you have any other ideas options? any kind of help will be really appreciated

[Mike Mackenzie]

One thing to keep in mind is you could hook up three systems to one blower however if this one blower were to fail all three systems would be non functional.

The fiber system does not require the amount of exhaust as the Co2 systems. So maybe three smaller blowers would be the better approach. Then again you would have three times the work three ducts, three electrical runs, three holes to cut etc.

[Lenin Alvarez]

i found out that we have a grainger branch on our back yard, we are going with the one big blower and variable speed, if it goes out we can get a replacement fast and we have the impell filtermate as a back up.

THANKS

[Michael Simpson Virgina]

Here is the thing. Say you need 400CFM. Just because a blower is rated at 400CFM does not mean you are going to get that at the laser.

I have done a lot of work with dust collectors and blowers over the years and have measured the final CFM after installing the duct work.

Currently I am using a 850CFM unit for my Laser but by the time it get to the duct work I am probably only getting a little over 500CFM. I would not consider anything less. Remember the manufacture CFM recommendations are the minimum. Also keep in mind the more CFM (within reason) you have at the laser the less cleaning you will have to do.

The length and diameter of the hose as well as the material and number of elbows will effect your final suction.

The problem with using a very large blower on several lasers is that the splitters don't reduce by a direct multiplier. In theory a 1500CFM with a splitter should yield two 750 lines. This is never the case. From experience you will be lucky to get two 600's from the splitter. Down the line you will be doing good if you get 300CFM at the piece of equipment.

I strongly recomend three 850 or similar blowers. Also if one goes down you can move an exhaust in a pince to a vital laser thats doing a particular job until you get it replaced.

[Richard Rumancik]

It will be complicated to balance the flow in the combined system. If you ALWAYS had 3 systems running it may be possible but I assume that at times only one of the three lasers will be running. In this case you should probably install blast gates at each laser so you can shut off the flow completely if the unit is not running. It could also be used to adjust flow as needed. Unfortunately, a blast gate is an obstruction that is not the best for efficient air flow.

Also, note that when a 2nd or 3rd unit comes "on-line" it will reduce the flow to the operating laser(s). So you may have 3 users competing for a limited amount of airflow.

You might need the help of a HVAC person to get this to work the way you need.

[Peter Meacham]

Lenin

I don't recommend the Harbor Freight blower - it is very, very noisy. I recommend the Penn State - it is much quieter - which I am using now that I have ditched the HF one.

Pete

[Joe Pelonio]

I have an 800 cfm from Grainger that worked fine at my commercial space where it ran about 20'. Here at the home shop it runs maybe 3', and likes to lift material up it's so powerful. If you put multiple machines on one line, make sure it's strong enough that a sheet of paper is held in place on the intake vents with it running. I don't know of an easy way to measure cfm but if the paper falls off it's probably not enough.

[Lenin Alvarez]

Thanks guys,

We have a HVAC guy comming in today ,he is going to do the installation and he is going to look for what is best for us, the installation will be done tomorrow (if weather helps), the new machines are will be here tuesday:D

I will let you know hoe everything goes