minimum exhaust airflow when engraving

[Niklas Bjornestal]

Does anyone know what the minimum needed airflow is when engraving. Since there is a lot less smoke compared to cutting it should be possible lower the airflow. I was thinking about having two exhaust systems, one high cfm for cutting, and one smaller quieter for engraving (95% of the time).

I have found a ducted fan that i think will be able to deliver about 100cfm. Will that be enough for engraving?

[Henri Sallinen]

My current (and only) fume extractor gives about 110-140cfm depending on the setting and is has been good for my needs. I cut mostly cardboard, matboard, cardstock and paper, so it doesn't give that much fumes. The extractor does ok if I sometimes have to laser plexiglass or wood, but more cfm would be nice.

I have run the extractor at about 100cfm when the filters are getting clogged and it seems to do a decent job when cutting my usual materials.

[Joe Pelonio]

Depends on how the tube is cooled. On my Epilog Legend, the manufacturer requires 400 CFM for enough air flow to keep the tube cooled. Less is asking for trouble. If yours is water cooled or has it's own cooling fan 100 CFM is probably enough for fume extraction only.

[Bert Kemp]

? Wouldn't that depend on the size of the bed, I'm pretty sure that a bed size of 9x14 would take a lot less cmf then a bed size of 36x48. Or maybe not, but It would be nice to know what laser and size he has.

[Niklas Bjornestal]

A gcc venus 12W, so small table. And it has its own fans for cooling the lasertube.

[Kev Williams]

You don't need much air flow to evacutate the smoke from engraving, but you want enough flow so as little smoke as possible is allow to float freely amongst all the moving parts. That smoke contains the remnants of wood sap, glue, plastic resins, oils, and whoknowswhat that will collect on the belts and drive cogs and such- Not terribly detrimental I'm sure but might as well keep it as clean as possible! Also-- good airflow can put out errant fires that may start, say, from the edge of a piece of transfer tape you may be engraving thru...

My suggestion- go to Harbor Freight and pick up one of these--hfblower.jpg
DON'T get the little red one, too noisy. And there's a bigger size, you don't need that either. This one is around $125 I think...
I have two of these, they move plenty of air, one is 13 years old, the other is 11 years old. They're outside the basement door, and they're quiet enough I forget to turn them off half the time, they run A LOT.

How's this, I just made a quickie vid to show how loud these blowers are. They DO make some noise, but note that NONE of my machines are on. When they are, just the fan noise and hum of them in 'standby' totally drowns out the blowers Which is why I forget to turn them off! With the basement door shut, it may seem loud, but I'd say at least 80% of the noise heard is directly from the air moving within the laser boxes...





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[Craig Matheny]

Depends on how the tube is cooled. On my Epilog Legend, the manufacturer requires 400 CFM for enough air flow to keep the tube cooled. Less is asking for trouble. If yours is water cooled or has it's own cooling fan 100 CFM is probably enough for fume extraction only.

Joe little confused on how the exhaust in the Epilog cools the tube being the tube is on the back of the machine with cooling fans on top of it?

[Niklas Bjornestal]

Thats way to noisy... the laser and fan will be in an appartment, in a room next to the tv-room where the rest of the family would like to be able to hear the tv

[Kev Williams]

So, how much noise is your laser going to make while it's running? Or the TV?
Since I'm in the mood to make movies, this one is more fair to the blower...





The ambient noise of the machine and the TV will drown out nearly all of the blower noise.
As for your apartment neighbors, that may be a different story!

[Joe Pelonio]

Joe little confused on how the exhaust in the Epilog cools the tube being the tube is on the back of the machine with cooling fans on top of it?

No, my tube is at the front of the machine with no fans to cool it. It's right in front of the front air intake slots. (I have changed it twice).

[Craig Matheny]

No, my tube is at the front of the machine with no fans to cool it. It's right in front of the front air intake slots. (I have changed it twice).

Interesting what unit do you have and what year I have a 45 and 60 watt mini and it is in the rear blower has nothing to do with the cooling the 45 is 2007 and the 60 is 2012.

[Joe Pelonio]

Interesting what unit do you have and what year I have a 45 and 60 watt mini and it is in the rear blower has nothing to do with the cooling the 45 is 2007 and the 60 is 2012.

2005 Legend TT, 45 Watt, there are fans to cool the power supply, in the back.

tt.jpg

[Craig Matheny]

Here is the layout of mine complete redesign I guess