Laser Exhaust Complete, First Test Fire

Completed the exhaust system for my FSL 5th gen laser today and did the first test fire! All seems well. First the exhaust, then some nit picks about the setup. As mentioned in the first post about the exhaust, I got the Harbor Freight 1HP dust collector, the router speed control, and this 4" blast gate. To complete the setup I ordered this 4" stay put flexible duct hose, and made a run to Home Depot for the following:

  • 4" x 5' metal rigid vent pipe
  • 4" dryer vent hood
  • two 4" 90 degree adjustable vent pipe elbows
  • 4" x 2ft alum. vent pipe
  • four 8"x8"x16" cinder blocks
  • 3 roofing shingles
  • four 2.5" 5/16 bolts/nuts/washers
  • 2 hinges

With all this and a bunch of spare lumber I had around, I built the exhaust box. I used 2x2 for the corner supports, 3/4" plywood for the side, 3/4" MDF for the base, and some 1/2" chip board for the top. The base is around 16" square, same for the back, front is 13" x 16", sides 16" with angle cut at top to make sloped roof. Basic layout is like so.


The blower is bolted to the MDF with some 2.5" 5/16ths bolts.


I then cut the holes for the intake and exhaust and screwed it all together. There is a notch in the back side of the floor to run the power cable through. Running it out the bottom keeps water from running down the cable into the box, this way it'll just drip off the bottom. Some duct was run between the exhaust and the dryer vent, and a 90 deg elbow for the intake both hose clamped on. I put some hinges on the top so I have access to change motor brushes or clean it out etc.


I threw some shingles on top for rain protection but we'll see how that goes. Also some aluminum tape around the inlet hole to keep water out.


The window insert is 1/2" plywood with a 4 1/4" circle cut into it for the blast gate and a notch for the power cable. The cable comes in the window and plugs into the router speed control with is mounted on the inside. I painted it black and am using cheapo foam pipe insulation as weather stripping and it works great.


The blast gate lets me shut off outside air to keep the tube from freezing in the cold. Pretty simple setup and it's pretty quiet when not running full blast, which I don't foresee doing too often as it's a LOT of air at full speed.


Pretty happy with the setup. Easy to remove if I need to move the laser, and pretty quiet for me. We'll see what the neighbors think.

Setup and Test Fire

Setting up the water pump and air compressor was pretty simple. They forgot to put in an air tube so I had to run to Petco and get a 1/4" OD air tube for $5. The air compressor comes with a splitter which is semi annoying as you have to block all the split ports since you just need one to go to the 1/4" OD air assist input to the printer. This is my ghetto quick rig just to test it. I'll come up with something better.

air pump

The air hose on the inside of the laser that come out of the coupler wasn't seated very well so I had to take the side panel off the laser and reseat it. Otherwise everything seemed well assembled. I threw some thermal paper on the bed and fired the pumps up and did a test fire and the laser looks well aligned. Ready to rock! Just waiting on the iMac to get here that will be used to run the laser so I can run an actual job! Can't wait.

Friggin Lasers
Posted on March 3, 2013 and filed under Laser.