Changed the junk air motor to this one. When testing them side by side this new one seems a bit less powerful.
But hey, it was only $15 and if it doesnt do the job, i just change it for something else 
Was curious to get a neat solution not taking alot of space behind the laser
What do you think, yay or nay? 
Whatās the link to it
ItĀ“s in Swedish, i translated the data below 
Airflow: 107 mĀ³/h // 63 CFM
Power: 14 W
Noise: 36 dB(A)
Speed: 2300 rpm
Almost as a regular computer fan, didnt notice that until now 
Maybe iĀ“ll do a test with stacked 120mm fans too
The problem is that itās not a squirrel-cage fan. It cannot generate a high amount of static pressure. It might be able to do 63 CFM with absolutely no obstruction, but itās got so low static pressure that it canāt overcome obstacles/turns/restrictions.
Iāve read regarding stacking fans (as I thought similar to use multiple 120mm fans) doesnāt really increase the output a great deal (definitely not double). Iāve thought it may be possible to funnel multiple side-by-side into the exhaust tubing.
My fanhttp://http://www.ebay.com.au/itm/111240702828?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT hardly need air assist now it is that good not cheap but will last years,ps with stock extraction fan cutting mdf 3 hours a day my laser tube is covered in mdf dust,
Tried the tube-fan i showed pic of above, it āworkedā but it didnt remove the smoke quick enough for my liking.
Was thinking about making positive pressure, by having fans in the front blowing in, and fans in the back taking it out, to get a better flow trough the box, without the need for monster fans.
Your ideas and tips are highly appreciated
The fan should always be the last thing in the hoseā¦ So it pulls a vacuum on the laser and doesnāt have to push air through the hose as wellā¦ That way it will never push smoke into the interior of the building.
@William_Steele Good thought, what about having the fan included with the laser at the back, and the new one i bought at the end of the hose? Maybe a bad idea, was just thinking if you got any experience on that
Thanks
I donāt recommend a fan on the back of the laserā¦ if there is any imbalance, then youāll wind up blowing smoke into the room.
Very quit,it is 2 meters out side and can just hear it running
I just added air assist [i had a air hose next to laser head blowing air across the work however bugger to aim and did not keep fumes from dirting focal lens] laser head from ebay cost 50 dollars bugger to align mirrors again ,and found out my laser head was out of square causing laser beam to hit side of air assist and not come out the end ,took 4 hours to align mirrors ans an hour to align laser head so that all is good now
