DanielBauen.com

Engraved the Boston Dynamics (of Big Dog Robot fame) logo on the back of the phone of my friend who works there.  The engraving looked stunning, and it turned out bright white.  

Settings:
Speed: 150mm/s
Power: 30%

Jelly fish flames wood box.  Cigar box which was sanded, engraved, and then coated with wax/orange oil.  I only learned later that the discoloration around the engravings can easily be removed with a wet rag.  The box was made in 3 separate steps.  Engraved the top, rotate 90 degrees, engrave the right side, rotate 180 degrees, and engrave the left side.  Unfortunatly, pictures don't do it justice. It looks amazing in person.

Settings: 
Speed: 500mm/s
Power: 50% (considering that 60% appears to be max power, ~20ma, while cutting) 

 
Other side of the box.

This light was built from surplus parts I had.  A 3W Luxeon Star LED from a headlamp that I upgraded, a cheap flashlight, a heatsink with a threaded plate, and a flexible arm.

The plastic lens was scratched with a brass brush to create a diffuse light.  This reduces glare, and is not blinding if you happen to look directly into the light.

Finished the laser cutter project!  There are still a few things to add, like the exhaust blower, and air assist.  Thanks to David and Greg for help on this project.

I had a stepper motor and matching belt pulled from a surplus printer that fit the Z-axis bracket, but did not have the matching pulley.  The belt is a 1.5mm pitch, which has tiny teeth.  1.5mm pitch pulleys are also not readily available, so I modeled one in Solidworks and printed it out on my 3D printer.  I was unsure of how the teeth would resolve due to their tiny size, and the resolution of the printer.  The printed part turned out to be functional.  The teeth are rounded quite a bit, but the belt still engaged properly.

The stock air assist nozzle left a little to be desired.  Being made from a chunk of aluminum, it was heavy, and the barb fitting was straight instead of 90 degrees (which made the air assist tubing stick out too far).

The DSP laser controller has an input for the autofocus sensor.  I thought it would be handy to have the autofocus sensor integrated into the nozzle.  The nozzle shown below is the result of these design requirements.  It has a spring loaded tip.  When the table is raised, and the part touches the tip, the electrical contacts inside the tip are lost, and the DSP autofocus input is triggered.  The table then lowers a specified distance away from the tip to achieve proper focal distance.

Design Patent Application Guide: http://www.uspto.gov/patents/resources/types/designapp.jsp

Forms: http://www.uspto.gov/forms/index.jsp#startforms

Obtaining a customer number: http://www.uspto.gov/patents/process/file/efs/guidance/register.jsp

Unnoficial Design Patent Application Guide: http://inventors.about.com/od/designpatents/a/design_patent_f.htm

The laser mounts supplied with the plastic parts kit from Buildlog.net were functional, but left a little to be desired.  

• My first concern was over tightening the screws, and breaking the tube. (when left to my own devices, I have a tendency to over tighten and break things) 
• The second was breaking the tube during transport due to an overconstrained condition if the frame flexed at all.  
• Third was ease of installation and removal of the tube.  I'd prefer to just set the tube in the pre-aligned mounts, then loosen at least 1 screw and try to slide the tube in from the end.

Alignment systems that are not subject to high forces, and use 3 point alignment method, generally have 2 points that are adjustable, and the third is compliant. It prevents over constraints, and is easier to adjust, because only 2 points need to be adjusted, and the third automatically moves to compensate.

If the laser mount was designed like this, then it would be easy to align the laser without the worry of breaking it.  Also, it eliminates the need to loosen one screw as the other is tightened.

I thought about wrapping the tube with a strip of rubber at the contact points, to allow for some compliance and prevent slip.  However, this makes all the points compliant, and adjustments would not be as exact.  Also, over time, the rubber can creep, and the laser could loose alignment.

Without knowing how strong the laser tube is, and not wanting to test that, I was concerned about using a spring loaded point.  I also did not know what the required strength of the spring would be to keep the laser in place.

A third of the mount with one of the screws was cut off. Using an extension spring that wrapped part way around the tube would help distribute the point force.  It also allows for compliance if the frame is twisted, and will prevent the laser from breaking.

Lightwave makes a great pair of bindings, but after purchasing them, I realized that my Liquid Force WLF kite board uses non-standard 6.5inch screw spacing. The screws for the Lightwave bindings are spaced at 6in apart.  The bindings have a metal plate through which the screws go through. I wanted to decrease the spacing to 5.5inch, because that would probably keep it stronger as opposed to widening the spacing more. I could just dremel the slot, but that would damage the metal support plate, and possibly make it too thin.