Archive for October, 2012

Inexpensive circular LED mill/drill light

October 14, 2012

Anyone who uses a drill or mill knows how difficult it can be to get the right light on the part you are machining. If the light is near you, you cast shadows as you move your hands in to manipulate the piece, and the light fixture can get between you and the piece.  If the light is behind the piece, then you can get glare in your eyes.  The best approach is a circular light, mounted around the mill itself.

After seeing the amazing circular LED lights that my friend, Ralph Lemnah, made, I wanted one.  I was not, however, willing to put as much work into my light as he did (he designed the circuits, designed the PC board, fabricated the PC boards, fabricated the enclosures, and then fabricated the mounting brackets!)

Then I stumbled across this item on eBay:

5050 85 LED Car Angel Eyes Light Circular Tube Ring Lamp 14W 220-240V 185MM

It costs $18 with free shipping.  While it claims to require 220 V AC to run, it actually runs just fine on 110 V AC. It is manufactured with four quadrants, each of which contains 22 LEDs and its own little power supply board; each power supply produces 62 volts.  This voltage is too high to repurpose these devices for use with a regular wall wart.

Note that the insulation on these wires is the softest I have ever seen: you can strip the wires easily with your finger nails.  You should not allow these wires to be exposed to rough use.

Here are some shots of the device after I disassembled it.  Note the metal backed PC board used for the quadrants.

I made a wooden adapter plate so that I could mount it to my mill.  I considered doing it “right”, with aluminum, but it seemed a shame to throw away so much aluminum to make the ring. The inner diameter of the plate just fits around the mill; I used a notched threaded rod as a set screw to keep the plate from dropping off of the mil (see red circle in the first picture)l. And, yes, the cable ties are ugly.  Still, the whole process only took an hour or so. I was careful to use a cable tie to ensure that an accidental pull on the power wire would not affect the soft insulation on the original wires.

Parrots demand a new box

October 14, 2012

In my constant quest to keep my African Gray Parrots entertained, I bought a small wooden box (kind of like an old fashioned chest), drilled a 4″ hole in it, and let them explore it.  That looked like this:

They liked it so much that I made a box that I could hang from the top of their cage, so they could play with it even when confined in their cage (when I’m away, or at night).  The first one looked like this:

Note the 8 hooks: I suspended the thing from the bars across the top of their cage.  Note the entry hole on the upper right side.  This is what it looked like once I had installed it:

And this is what it looked like a month later:

Only 2 out of the original 8 hooks still intact, with essentially every piece of wood chewed.  I figured that they needed a box that would last just a tad longer, so I made this one:

It is made out of 2×6 lumber, and the 6 hooks are 2.5 inches long. Here are the two boxes, side by side:

I considered putting a top on this one, to keep them from chewing it, but since they seemed to like chewing it, I figured I would leave the design as is, for the time being

I’ll keep you posted

Solidoodle 3D printer damaged: shipped by UPS

October 6, 2012

I purchased a used Solidoodle 3D printer, and looked forward to its arrival today.  The packaging was stunning, both outside the printer, and inside.  The printer box was stuffed solid with bubble wrap.  After I carefully pulled the bubble wrap out, I was stunned to see that the printer was totally trashed inside.  I have no idea how UPS managed to perpetrate this much violence on the box.  Here are some pictures of the damage.

The mountain of packing material shows how well it was packed.

One side of drive belt snapped off from the mounting bracket

Another broken bracket

Back of printer from above.  The two vertical rods snapped out of their retainers and were pulled forward and down.

The threaded rod along the back of the printer snapped with the force

You can see the two retaining holes out of which the vertical rods fell when the box was dropped. Once the rods were loose, they put too much pressure on the plastic brackets on the sides, which then broke.  At that point, the lever action broke the threaded rod.

This damage might have been avoided if the rods had been 1/4 inch longer: they just barely sit inside the two holes.  This may be a design flaw, at least when the printers are shipped.  I’m sure everything works fine when the printer is stationary.  Of course, if the bed had been at the bottom instead of the top, the threaded rod might have been subjected to less force.  And I suppose everything could have been held in place with cable ties.  I do not know what the standard procedure is for shipping these printers from the factory. This was not shipped from the factory, but rather from the original purchaser.

The bottom of this bracket has a huge hole broken out of it

The two horizontal rods hanging down after the bracket that held them broke off.  The back of the printer is to the left.

The other side of the two horizontal rods. The back of the printer is to the right.

Another shot of a broken bracket

The horizontal rods dangling, looking in from the front of the printer.

The extruder lying on top of the bed

This is how it looked after I first removed all of the bubble wrap from inside the box

I’m pretty thoroughly bummed: I was hoping to start printing tonight!