You should be able to find some plans for an DIY version of what is called a fog buster. I think what was the magic was pressurizing the coolant before injecting it into a airstream.

Actually I did see that and have already ordered one. I did think about building one of the plan based ones, but I really did not want to get side tracked on another project.

Fogbuster testing
 

I got the fogbuster in and it is working well so far. I have used it to cut a couple of 1/8 aluminum parts. I set the air pressure to about 10psi and and adjust the coolant flow to get just a light film on the surface. That is enough to keep the bit lubricated and blow the chips away. I have used the same cheap bit twice and after each run I have inspected the bit. Minimal wear and no signs of chip welding. A remote air switch is included that makes it convenient to turn off the air flow after a run.

I think the only complaint I would have about the unit is that for the price I paid they could have included more than 5 feet of hose. I will have to get some more hose if I want to do anything that would be more than a few feet in size.

I found a pressure foot on AliExpress I have ordered. Hopefully that will arrive in a few weeks. Once I get it I will attempt to do thin sheet cutting again. I have a few more thin sheet aluminum parts to cut as well as several plastic parts.

For keeping thin sheets down on the bed I like to use shelf liner paper and spray adhesive. Apply the shelf liner to both your sheet of aluminum and table. Spray on some adhesive and basically glue the 2 pieces of shelf liner together. I have cut sheets all they way down to .020 thickness with this method.

Cutting Sheetmetal
 

Finally I can report success cutting sheetmetal. Both aluminum and steel
The first pic is the setup on the machine. On the left is the fogbuster. To the right is a pressure foot I purchased off of AliExpress and just got in today.

The second pic is an IV cart repurposed to hold the coolant for the fogbuster and make it easier to use in other locations.

The third pic is some metal parts cut. The part made is a rear spar attach batch bracket. It is used to connect the rear spar to the fuselage. The real part cut from 1/8" aluminum in on the left. The middle one is a test done in .032 aluminum. The right was cut from 20 gauge steel.

There is still some tuning to do. There seems to be a bit of bit deflection going on. Also the steel part has a bit of nasty burr on it. Still the fact that I was able to cut all three of these without destroying a bit is major accomplishment for me.

Very nice, tell us more about that attachment on the bottom of the spindle, I assume its a type of hold down/ pressure foot?

I purchased the pressure foot here. There are other spindle sizes available if you search on the site.

What makes this foot a little different from ones I have seen before is the use of a ball bearing pad on the bottom. The unit arrived with one defect. A tab was bent causing it to drag. I had to disassemble the bearing assembly to bend the tab back straight.

The springs in the hold down arms are very very stiff. I can compress it about 1/4 inch before my z-axis jumps on the rack. For the .032 and .040 metal thickness I tested against it worked just fine and moved smoothly. I may pull the springs and cut a few links or replace them.

I am a little concerned about chips getting inside the bearing assembly and requiring cleaning.

While I did have to pull my dust foot off the spindle, there was no problem attaching the pressure foot. After zeroing my z-axis, I loosened the foot, dropped it to the surface of the material and retightened. It is possible to swap out bits without pulling the foot, but it is a tight fit for the wrenches. Pulling the foot is very easy though so it is just as easy to do that.

Great info DB. Thanks!!

Plotter Pen
 

Since I am now able to cut aluminum sheet, I also want to be able to accurately draw site lines on sheet metal when I am doing bending. I never have been able to find a pen holder already out there that I really liked and I have tried a few. My ideal pen needs to be inline with the spindle and have minimal play at the tip.

I finally decided to make my own. It is a tube in tube design. What makes this different than others I have seen is a taper on the inner tube that matches the taper of the mini sharpie. This creates a tapered interference fit that makes the pen self locking and keeps it centered with the spindle.

I have the inline requirement. I am waiting for a reamer to come in so I can get a little tighter fit between the tubes. I did not have the correct size drillbit or reamer so I am currently seeing about 2mm free play at the tip. I want to get that down to at least .5mm.

Great idea, let us know how it finishes out

Plotter Pen, Material Stand and Welding Jig
 

First thing, I had forgotten about the plotter pen post I had made. The pen has been working well and with minimal slop. I consider it accurate enough to do combined operations with both cutting and marking up with the pen.

The problem is that the design relies on a particular barrel style of Sharpie that they no longer supply! No problem for me because I had bought a big lot of them off of ebay a few years back. However without a supply, any thoughts of making more to sell are at a dead end.

On a different subject. I have wanted a material stand that has the acme screw adjustment that I see on pipe stands. However I could not find any around for more general material holding. So I fabricated one of my own.

Part of the design includes welding up a tripod. However with three legs I needed some way to hold everything up together. I really could not find any welding jigs that I really liked for holding things up, so I constructed my. Picture below. I also made a short youtube video at https://www.youtube.com/watch?v=hXcFoEXwUQo describing the stand and jig.

Optics Lens Holders
 

While the airplane is an ongoing project, I have been wanting to experiment with optics for a while. The biggest problem is holding the lenses, which having a mechmate makes easy to solve. I have already been doing some experimenting, but todays run was to make 16 new holders for a collection of lenses purchased from surplushshed.com

The first pic is while cutting. The second pic below is finished examples of a beamsplitter holder, iris and lens. The final pic is a small optical breadboard configured for a Michaelson interfereometer.

The aluminum posts and stands were done manually on my lathe and mill.

I did not drill the holes for the breadboard on the mechmate, but if I decide to build a larger breadboard I will use the machine to drill the holes. Doing 144 holes was a bit tedious.

I assume this is for laser?

The only laser at this point is a 5mw laser. The interest for now is just general experimentation and learning. So in addition to the interferometer I will do some microscope experiments, schieleren, autcollimator, etc. Perhaps what I learn from all this may make doing some kind of high power laser project possible.

That's way beyond my little co2 laser project! I'd like to see some more as you go along.