DIY Air Assist?

[Ginger Bosak]

I read tonight about DIY air assist.
Can anyone enlighten me more about how to go about doing that for my 35w ULS. I spoke with my rep tonight and he said the air assist from him would cost $1250 and then i would need $150 air compressor and the service technician to come help me set it up for $200.

We currently have a large air compressor that we are going to run a second line to...

So if anyone can help me save the air assist money, i can upgrade my wattage. :D

Thanks

Ginger

[Mike Mackenzie]

Ginger,

The air assist package for 1250.00 is what it is. You can use your shop compressor you will just need to install a water trap, coalsing filter, regulator, and a shut off valve inline before the laser.

Because the air assist set-up is more than just blowing air onto the cut it requires a little more work to install it. It basicaly runs a curtain of air over and around every optic in the system so its a little more involved on the installation.

All of the filters are available from Grainger You can see a PDF file of how we would install the air line to the compressor from this thread.

http://www.sawmillcreek.org/showthread.php?t=33954

[Mike Ross]

Hi Ginger, thanks for getting this thread started.

I too am very interested in DIY air assist. I have an older 25W uls. We have a shop compressor and are very familiar with air dryers and getting regulated dry air to the machine.

Mr. Mackenzie: Looking at the .pdf you referenced above it shows how to get dry air to the machine. That is great information and very helpful, thank you. You also mention factory air blowing over all the optics in the system. That sure sounds like the way to go but more than I am willing to put into this age/size machine.

I see other folks have posted saying they are pleased with a piece of aquarium tubing and a flow control valve.

Is just a stream of very dry air directed at the cut beneficial? I am interested in pictures/descriptions of any DIY systems that folks have had success with. Would really like to see how you attach the nozzle and tubing to achieve the airstream on your cut line without encumbering the motion systems. Also, do you direct the air right at the cut? Is the air directed from the leading or following edge?

Thanks so much, this is a great resource with first class folks.

Mike Ross

[Mike Hood]

I wouldn't hesitate to add air assist on your own. I also live in Washington state and I don't do anything special. I have a 20 year old Craftsman compresor... a water trap and use a flow valve on my air intake at the laser to adjust flow.

Air assist is nothing more than air... just pointing at the cut. You can get directional "jointed" tubing at places like those used on scrollsaws and build your own with no problems.

I do have a MAC valve I'm gonna installed to let the laser turn the air on at the beginning of the cut, but it's just a nice extra. Turning the valve by hand works equally well. Don't get suckered into a $1000 compressor :)

[Rodne Gold]

The air assist is merely a confugurable nozzle that can be directed at the cut and a way of controlling air flow (simple valve) , use aquarium tubing. Only thing you have to bear in mind is to allow the flying head to be able to move without the lines fouling and to minimise the weight of any lines that add to the flying heads inertia. You dont even need clean dry air if you arent pressurising your optic chambers. I cant see the tubing/valve setup costing like more than $75.
As to a compressor , well that your choice , we use shop air , only thing about those small hobbyist compressors is that they not designed for coninuous operation and are irritatingly noisy.

[Rob Bosworth]

There are a couple of different designs for air assist assy. The most efficient way to introduce air flow to a laser cut is to run the assist air down through a nozzle straight down to the cut. This nozzle will have the laser beam run down through it and the air blows down directly into the kerf of the cut. You will achieve your most consistent cut results where the assist gas runs down perpendicular to the cutting surface. The only drawback to this design is, you have to have your air assist blower on whenever you are running with a nozzle on the system. If you don't have your assist air on when laser processing, these nozzles tend to act like a vacuum cleaner for all of the hot effluents to go up and build up on the lens. A very quick way to fry a lens$$$$$$$$$$$.

Another way to introduce air assist to your system would be to blow air across the cut area of your material. You are really only blowing the "flame" out or the effluents away from the plume, but for most laser engraving application that is OK. You can achieve this kind of air assist by running a tube down along the lens assy. of the machine, and point it towards the laser processing spot. Or you can blow air across the material from an air source at the front of the machine, and point it along the material being processed towards the exhaust port of the machine. The drawback to either on of these air assist designs that blow across a material rather than straight down into the kerf is, you will get a little different cut quality with different directions of movement from your laser system. Some directions, the will actually go down into the kerf, and others it will only blow across the kerf.

[Ginger Bosak]

Does anyone have a photo of what it looks like attached to the machine. My husband said that he works better with following a photo

[Mike Mackenzie]

Here is a link for an after market air assist set-up.

http://www.hltlasers.com/index.php?location=accessories

[Dean Flannery]

I use a 4" muffin fan setting in the front of the table and blowing over the work piece toward the vac system in the back.
I used to clean my optics 2-3 times a day, since I put the fan in they only need cleaned once every couple of weeks

[Dave Jones]

Here's a photo of the mirror/lens assembly on a Epilog, with the air assist hose being the bent tube in the pic.

http://www.epiloglaser.com/air_assist.htm

The Epilog uses the second system Boz described where the air is blown down close to the line of the beam, but hits the lasered spot at a bit of an angle rather than coming straight down in a cone nozzle that is around the beam. I think the Epilog method is maybe not quite as effective as the cone method, but it is also, I suspect, a lot easier to build yourself.

Here's a pic of the cone that ULS lasers mount under the lens for the air to flow through.

http://www.ulsinc.com/english/laser_systems/product_line/accessories/coaxial_comp_con.html

The hose on the epilog is a thin coiled hose that connects to the metal tube above the laser mirror/lens assembly and stretches parallel to the x axis arm. a second coiled hose goes from a fitting at the end of the arm to the back of the case, where another fitting goes through the case and the hose from the compressor is connected.